Robert J. Hamers - US grants

Scanning tunneling microscopy will be used to study how low coverages of chemically active surface modifiers, to include sulfur, oxygen, and phosphorous, affect the adsorption and dissociation of small molecules of catalytic interest, such as carbon monoxide, methane, and methanol, on transition metal surfaces, such as molybdenum (100), tungsten (100), and nickel (100). STM will be used to image molecules and impurities, and to probe local variations in atomic geometry, electron structure, and work function. The goal is to control electronic structure modification, and the ability to tune chemical reactivity.

The research project of this Presidential Faculty Fellow is in the general area of analytical and surface chemistry and in the subfield of surface microscopy. During the five-year tenure of this award, Professor Hamers and his students will utilize scanning tunneling microscopy (STM) and related techniques to observe, understand, and control the surface chemistry of solid state materials at an atomic level. These important goals will be pursued by using STM techniques to identify molecular surface species; through the integration of STM with other chemically sensitive techniques such as infrared absorption spectroscopy; through the development of novel scanned probe techniques which could provide new methods for achieving elemental and/or functional group identification on nanometer distance scales; and by making use of the STM tip as an active tool for inducing chemical changes in this distance domain. %%% The successful attainment of the goals of this project should give rise to new techniques for the atomic-scale characterization of solid surfaces as well as innovative chemical insights regarding surface reactions which are of immense technological significance. Additionally, this Presidential Faculty Fellowship should significantly assist Professor Hamers in the continuing development of his vital and productive program of research and research training.

Hamers The use of scanning tunneling microscopy (STM) to study chemical reactions has been hampered by the inability to a priori identify adsorbed molecules and molecular fragments. The goal of this work is to overcome this limitation by first studying a homologous series of unsaturated hydrocarbons, their decomposition products, and some functionalized derivatives of these molecules to develop an empirical basis set for molecular identification, and then applying this knowledge to study the reaction chemistry of these hydrocarbons on surfaces of Pd, platinum, and nickel both in the absence and in the presence of "modifiers" such as sulfur, chlorine, and silicon. Studies will be performed using a unique scanning tunneling microscope system which can image surfaces at 77 Kelvin in ultrahigh vacuum, in conjunction with other techniques including infrared spectroscopy, Auger, and low-energy electron diffraction. STM will be used to provide atomic-resolution analysis of the identity and spatial location of molecules and molecular fragments and to directly observe the influence of steps, defects, and chemical inhomogeneities on the reactions of small unsaturated hydrocarbons on metal surfaces, while FTIR will provide information on the chemical functionalities present on the surface. A statistical analysis of this spatial information will be used to quantitatively describe the surface lateral chemical composition and to identify spatial correlations between the positions of various surface species. By studying the adsorption and decomposition of small hydrocarbons on metals, the adsorption of chemical modifiers, and co-adsorption of molecules in the presence of modifiers, we will achieve new insight into the nature of heterogeneous catalysis at transition metal surfaces. %%% The explosive growth of scanning tunneling microscopy as an atomic-resolution tool for probing the geometry and electronic properties of surfaces brings with it exciting new opportunities to probe materials chemistry at the atomic level. However, the use of STM to study chemical reactions has been hampered by the inability to a priori identify adsorbed molecules and molecular fragments. The goal of this work is to overcome this limitation by first studying a homologous series of unsaturated hydrocarbons, their decomposition products, and some functionalized derivatives of these molecules to develop an empirical basis set for molecular identification, and then applying this knowledge to study the reaction chemistry of these hydrocarbons on surfaces of Pd, platinum, and nickel both in the absence and in the presence of "modifiers" such as sulfur, chlorine, and silicon. These studies will provide a fundamental basis of knowledge about the appearance of various molecular fragments in the STM which can then be applied to study the reaction chemistry of a wide range of molecular functionalities, and will provide insight into how promoters and poisons modify the reactivity of metals toward hydrocarbon species.

This award in the Environmental Geochemistry and Biogeochemistry Program is jointly supported by the Divisions of Earth Sciences, Chemistry, and Chemical and Transport Systems Engineering. Jillian F. Banfield, Geology Department, and Robert J. Hamers, Chemistry Department, of the University of Wisconsin-Madison will investigate at an atomic level the nature of reactions occurring at interfaces between aqueous solutions and surfaces of metal sulfide minerals. They will use a multidisciplinary approach, incorporating biological, geological and chemical factors, and integrate results from a wide array of experimental methods, including STM, XPS, and confocal microscopy. Parallel field and laboratory studies will be conducted. Surfaces formed as a consequence of natural inorganically- and organically-mediated weathering will be compared to synthetically-weathered minerals to explore the applicability of laboratory-based studies to natural systems. The goals of the investigation are to determine the mechanisms and rates of dissolution, precipitation, and ion adsorption at metal sulfide surfaces; the effect of electrochemical oxidation and reduction on surface morphology; the role of impurities in modifying rates of electrochemical processes at surfaces; and the role of bacteria in controlling surface microstructural characteristics and dissolution rates. Chemical weathering of minerals is the process by which rocks are converted into the constituents of soils and sediments. Sulfide minerals such as galena, sphalerite, and chalcopyrite are mined as sources of important elements, such as lead, zinc, and copper, releasing the metals and acidifying water. The increase in acidity accelerates weathering of other minerals. Understanding the dissolution and crystallization behavior of metal sulfides, by chemical and bacterial routes, is important to developing predictive models of metal speciation and bioavailability. The goal of this study is to improve understanding of natural systems and to develop accurate laboratory tests and predictive models.

The reaction of the Si(001) surface with unsaturated organic molecules via a 2+2 cycloaddition is studied in this research project supported by the Analytical and Surface Chemistry Program. Professor Hamers and his students at the University of Wisconsin will study ordered organic films formed by this route using scanning probe microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. These organic films can be derivatized, and functional strategies developed to form overlayers with specific electronic and optical properties. The chemical and structural properties of these films are correlated with the possibility of interesting electrical and optical properties. The spatially dependent probes used to characterize these overlayers allow the determination of the spatial anisotropy which is expected to arise. The adsorption of unsaturated organic molecules on the silicon surface forms the focus of the research supported in this project. The ability to develop a flexible synthetic chemistry for organic films on silicon promises to allow the connection of silicon process technology for electronic devices with the broad range of properties possible with organic overlayers. A range of spatially dependent methods will be used to characterize the structure and properties of these synthesized overlayers.

This award in the Environmental Geochemistry and Biogeochemistry Program is jointly supported by the Divisions of Earth Sciences and Chemistry. Drs. Jillian F. Banfield, Geology Department, and Robert J. Hamers, Chemistry Department, of the University of Wisconsin-Madison will investigate effects of microbes on pyrite surfaces. Abundant organisms (bacteria and archaea) have been shown to attach to pyrite and to occur in the low pH solutions produced by pyrite dissolution. The mechanism of `direct` biological catalysis of pyrite dissolution involving attached organisms is poorly understood, however, as are the geochemical controls on the distribution of attached and non-attached Fe and S oxidizing organisms. In this research, the abundance and distribution of chemolithotrophs will be studied as a function of pH, ionic strength and geochemical conditions. Attachment sites for organisms will be correlated with surface morphology using precharacterized surfaces and cultured microbes as well as microbes in the natural environment. The polymeric binding layer whereby microbes attach to pyrite will be studied at low pH and the relationship to pyrite dissolution determined. The results will be compared to kinetic data from field studies of acid mine drainage generation. Experiments will be constrained by both molecular biological information about the relevant species at the site and physical and chemical details of the solid-liquid-organic interfaces. The role of bacteria in acid mine drainage is not well understood. Until recently, only chemical and geological factors were considered in models for dissolution of iron sulfides (pyrite) at locations such as Iron Mountain (Redding, California). The identify of some bacteria associated with iron pyrite dissolution was determined in previous work. Here the role of bacteria in dissolution of the metal sulfides will be determined. Factors such as how bacteria attach to mineral surfaces and how transport of metals is affected by that attachment will be explored

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Hamers
The nanometer-scale growth, structure, and morphology of extensively conjugated p-electron systems will be investigated. This research is focused on conjugated p-electron systems such as sexithiophene, polypyrrole, and other solid materials that are organic conductors of electricity and/or have novel optical properties as a consequence of their conjugated p systems. The proposed research focuses on strategies for preparing and for characterizing conjugated systems in which the properties are highly anisotropic due to the local orientations of the molecules on the surface. Several schemes for achieving molecular orientation will be investigated, including the use of oriented bonds at the surface and the use of vicinal surfaces with high step densities. A wide variety of structural, chemical, electrical, and optical probes will be utilized to link the molecular structure and bonding with the resulting electrical and optical properties. Scanning tunneling microscopy will be used to investigate the structural order and the orientation of the films, while near-field scanning optical microscopy (NSOM) will be used to probe the local optical response. Reflectance-difference anisotropy spectroscopy will be used as a non-contact method for evaluating the degree of molecular orientation.
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The proposed research will benefit society in several ways. First, through training of future scientists. The proposed research is quite interdisciplinary in scope, bridging gaps between synthetic chemistry, physical/analytical chemistry, and physics. Students and postdocs trained under this grant will receive the kind of interdiscplinary training that is needed for successful scientific careers. Secondly, the proposed research itself would benefit society in new ways. It is generally recognized that the advances in microelectronics technology over the last 25 years that have lead to the "computer revolution" cannot continue indefinitely using conventional approaches; the use of molecules as fundamental building blocks represents a new paradigm for microelectronics that, if successful, might enable new types of devices orders of magnitude smaller than those existing today. Organic light emitting diodes, for example, can in principle have efficiencies much higher than existing light bulbs, with the promise of great savings in energy costs; successful fabrication of such structures requires a significant research effort into the electrical conductivity and optical properties of organic then films. This project is co-funded with the Chemistry Division and the Office of Multidisciplinary Affairs.

surface property

This research project, carried out in the laboratory of Professor Robert Hamers at the University of Wisconsin-Madison, is concerned with the organic functionalization of group IV semiconductor surfaces, specifically the (001) surfaces of Si, Ge, and diamond. With the support of the Analytical and Surface Chemistry Program, Hamers and his coworkers are investigating the reaction of various organic molecules with the double bonded dimer species present on the (001) surfaces of these semiconductors. This is a route to the modification of these surfaces with organic overlayers, and the use of this chemistry for the subsequent functionalization of these materials. Applications of this chemistry to the construction of molecular electronic devices, and the developing "gene chip" technologies are clear.

The ability to attach organic molecules to semiconductor substrates in a controlled and reproducible fashion is the focus of this research program. If a reliable route to the attachment of organic molecules to these surfaces can be developed, the synthetic power and diversity of organic chemistry becomes available for the functionalization of these materials for applications in electronic device fabrication and in bioanalytical chemistry. A range of scanning probe methods coupled with ultra high vacuum spectroscopic probes is used to characterize and understand this interfacial chemistry.

This proposal was submitted in response to the solicitation "Nanoscale Science and Engineering" (NSF 01-157). The aim of this project is the development and use of biologically modified nanotubes and nanowires as electrical probes of biological activity. Researchers will develop a new type of nanoscale probe, the "nano-coax", that can serve as a molecular probe only nanometers in dimensions. This new probe involves attaching biomolecules specifically to the end of silicon nanowires and carbon nanotubes, providing a very highly localized sensing region. The electrical response of the nanoprobe will be measured over a wide frequency range from kilo-Hertz to Giga-Hertz. The researchers will also explore the use of the nanoprobe as a molecular-scale actuator, using an applied electrical control signal to induce a change in activity of biological molecules tethered to the end. The research involves an interdisciplinary team of chemists, molecular biologists, and electrical engineers. The outcome of the research will be the development of a new set of bioanalytical tools able to rapidly detect biological species with unprecedented selectivity and sensitivity approaching the single-molecule limit. Successful use of nanoprobes as biological actuators would permit the direct manipulation of biological processes at the nanometer scale. The research involves a large component of graduate and undergraduate education and training. Graduate students will work together with faculty and undergraduate students as part of an interdisciplinary team. Faculty researchers will train graduate students and undergraduate students in state-of-the-art methods of materials fabrication and biological analysis, providing a workforce well-trained for industrial and academic research.

This project is aimed at the development of a revolutionary kind of biological sensor. Recent advances have led to the development of tiny wires ("nanowires") only a few nanometers in diameter. In this research project, an interdisciplinary team of scientists will fabricate nanowires and then attach biological molecules, such as DNA and proteins, to them. The researchers will then investigate the electrical signals generated when these "nanoprobes" interact with other biological molecules. The research has the potential to lead to major advances in the development of highly sensitive detectors able to identify minute quantities (perhaps as little as a single molecule) of biological molecules. The researchers will also explore the use of nanometer-sized probes to induce changes in biological activity, with long-term potential for biomedical applications. This project is co-supported by the Division of Materials Research, the Chemistry Division, the Division of Bioengineering and Environmental Systems, and the Chemical and Transport Systems Division.

Chemistry (12) An inductively coupled plasma emission spectrometer is being purchased to develop and revise research-based projects in the undergraduate quantitative analysis laboratory course. Current laboratory projects focus on acid mine drainage as a way to investigate geochemical transformations of metal sulfide minerals and the release of metals into aqueous phases. In the initial parts of the course students become familiar with various tools in quantitative analysis, after which the equipment serves an integral part of extended, inquiry-based laboratory projects that are largely designed by the students themselves, but based upon research literature.

Abstract
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Hamers/Wisconsin

With the support of the Analytical and Surface Chemistry Program, Professor Hamers and his coworkers at the University of Wisconsin-Madison are examining routes to the surface modification of diamond and silicon surfaces. Photochemical and electrochemical modification routes are developed that will allow the attachment of chemically and biochemically interesting species to the surface of active semiconductor materials. Robust chemical and biological sensor platforms result from the attachment process. Readout of these sensor structures is accomplished through the application of electrochemical impedance spectroscopy.

The ability to selectively modify and control the attachment of proteins and other biologically important molecules to semiconductor surfaces is important for the development of sensor systems. With the support of the Analytical and Surface Chemistry Program, Professor Hamers and his coworkers are exploring novel photochemical and electrochemical methods for the modification of diamond and silicon surfaces. These robust sensor structures are then characterized using electrochemical impedance spectroscopy. This work promises new routes to important chemical and biochemical sensor arrays.

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This research is aimed at developing a new generation of biological sensors with two unique elements. First, the sensors are based upon the use of direct electrical impedance measurements as the basis for signal transduction, providing a direct electronic bio-interface and the possibility of real-time, continuous monitoring of biological molecules, including a wide variety of pathogens. Secondly, the sensors are based upon the use of carbon-based materials, including diamond and diamond-like carbon, as ultra-stable supports, to provide a robust chemical and electronic interface to biological molecules. The researchers will conduct experiments aimed at developing optimized biological modification of the carbon-based materials (including glassy carbon, thin-film diamond, and a variety of thin-film diamond-like carbon materials) and the subsequent use of the biologically-modified surfaces as the basis for direct electronic sensing.

This research will have broad impact by leading to autonomous sensing systems that are able to detect and identify a variety of biological pathogens in real time on a continuous basis. The development of these sensors could lead to complete low-power, battery-operated sensing systems that could be inexpensively and widely distributed to provide greatly increased security against hazardous biological agents. Much of the proposed research would also have broad commercial applicability in areas such as food safety, by enabling improved methods for continuous monitoring of a wide variety of biological pathogens. The proposed research will also effectively link research with education in several ways. The principal investigator is actively involved in a number of outreach activities linking the university to K-12 education. Additionally, graduate students trained through this proposal will be exposed to an unusually interdisciplinary field.

Abstract
CHE-0613010
Hamers/Wisconsin

The fundamental mechanisms of the photochemical and electrochemical functionalization of diamond and other carbon material surfaces forms the focus of this research carried out in the Hamers laboratory at the University of Wisconsin-Madison. With the support of the Analytical and Surface Chemistry Program, Professor Hamers and his coworkers are examining methods to integrate biological molecules with microelectronic systems. Photochemical and electrochemical patterning methods are being explored, with the goal of developing robust attachment strategies key to biological sensor applications. Outreach to local students in middle school and high school, and mentoring of research students at all levels is an important broader impact of this work.

Functionalization of semiconductor surfaces with organic and biological molecules is the focus of the research being carried out in the Hamers laboratory with Analytical and Surface Chemistry Program support. Spectroscopic probes and mechanistic studies are being applied to develop an understanding of the photochemical and electrochemical functionalization routes developed in this laboratory. Applications to biological sensors, biocompatible implants, and bioanalytical chemistry are resulting from the fundamental science of this research.

This project will investigate the formation and characterization of hybrid nanostructures linking vertically aligned carbon nanofibers with electrocatalytic metals and molecular materials. Electrocatalytic reactions underlie many emerging technologies such as fuel cells, but are limited in efficiency and by the high cost of many catalysts. This research will explore a new generation of designer interfaces in which nanostructured substrates are coupled to electrocatalytic centers through well-defined molecular groups in order to optimize the electron-transfer properties of the interface and the resulting electrocatalytic efficiency and selectivity. The grant will also provide training opportunities for graduate students in cutting-edge areas of interface science and will provide opportunities for faculty and graduate students to mentor K-12 students conducting independent research projects.

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The project focuses on materials and interfaces crucial to emerging technologies for storage and conversion of energy between electrical and chemical forms, such as fuel cells. Novel types of carbon-based nanoscale materials exhibiting unique properties will be linked to catalysts that can enhance the rates of chemical transformations with significantly reduced use of energy. The proposed work has the potential to significantly improve the efficiency and lower the cost of important chemical transformations. Priority will be given to training for graduate students in areas of science and technology crucial to future developments in energy science. Priority will also be given to providing opportunities for K-12 students to conduct research projects at the university in these areas.

With support from the Chemistry Research Instrumentation and Facilities - Multiuser Instrumentation (CRIF-MU) Program, the Department of Chemistry at the University of Wisconsin will upgrade a cyber-enabled electron paramagnetic resonance (EPR) spectrometer. Research projects to benefit from the EPR spectrometer include studies on 1) the interaction between high-valent metal centers and redox active units; 2) the biosynthesis and reactivity of adenosyl-cobalamin; 3) gas sensing metalloproteins; 4) silicon spin resonance for quantum information processing; 5) organic molecules that occur in interstellar space; and 6) low-coordinate and multiply-bonded compounds of silicon, germanium, and tin.

An electron paramagnetic resonance (EPR) spectrometer yields information on the molecular and electronic structure of molecules. It may also be used to obtain information about the lifetimes of free radicals, short-lived species that are often essential for the initiation of tumor growth and/or a variety of chemical reactions. The EPR spectrometer will undergo a cyber-infrastructure upgrade to allow remote control by several academic institutions with significant populations of underrepresented minorities.

This award provides support for a two-day workshop that would bring about 60 participants together to discuss the issues, challenges and opportunities in "Materials Education" and devise strategies for synergizing all stakeholders involved for further progress. "Materials Education" here refers to interdisciplinary education in the fields of materials science and materials engineering including physics, chemistry, engineering, and increasingly bio-related materials. This meeting will be held in early Fall at a venue near NSF. The workshop discussions will be focused on 4 topics: (1) Educating the public about the relevance of materials research through successful outreach; (2) Materials education for K-12 students and teachers; (3) Revolutionalizing undergraduate education toward flexible curriculum that includes multidisciplinary training; (4) Materials education for graduate students to prepare materials scientists and engineers with the skills to succeed in today's global research and development environment. The participants are expected to be those in a position to introduce change in the educational programs not only at their institutions but on a national level.

The meeting format includes half-day sessions consisting of keynote speeches and break-out group discussions followed by a common panel discussion on each topic. The anticipated outcome is a roadmap to enhance materials science and materials engineering education at all levels. A report which captures the conference discussions and recommendations to guide future planning by the materials community, professional societies, funding agencies, and others with strong materials education initiatives will be published within a few months following the conference.

This workshop is jointly funded by the Division of Materials Research(DMR), Physics (PHY), and the Office of Multidisciplinary Activities (OMA) within the Mathematical and Physical Sciences (MPS) directorate and by the Division of Research on Learning in Formal and Informal Settings (DRL) and Undergraduate Education (DUE) in the Education and Human Resources directorate.

Professor Robert Hamers of the University of Wisconsin-Madison is supported by the Analytical and Surface Chemistry Program in the Division of Chemistry to investigate the use of molecular layers as electronic interfaces to oriented single crystals of TiO2 in the anatase and rutile forms, and extending to other oxides including SrTiO3. Studies will focus primarily on single crystals but will also use nanocrystalline materials as appropriate. The studies are aimed at achieving a fundamental understanding of how differences in surface structure impact the resulting molecular layers and the electronic properties of the interfaces. The structural and electronic properties of these grafted layers on well-defined single crystals of oxide semiconductors will be evaluated using a variety of chemical, structural, electronic, and spectroelectrochemical probes. Oxide semiconductors are the basis for several new and emerging types of dye-sensitized solar cells, quantum dot solar cells, and photocatalysis devices. The ability to integrate these materials with molecular and nanostructured sensitizers could lead to the development of inexpensive solar cells made by simple wet-chemical methods. The educational activities include mentoring of 8th grade students on science projects in renewable energy, summer internships for high school students, and year-round research opportunities for undergraduates and graduate students.

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).

With support from the Chemistry Research Instrumentation and Facilities: Multiuser program (CRIF:MU), the Department of Chemistry at the University of Wisconsin - Madison will acquire an upgrade to the Chemistry Computing Facility. The upgrade includes a number of components, including: (1) the purchase of mixed shared-memory and Beowulf cluster computers; (2) the creation of secure, cyber accessible systems; (3) the purchase of servers and file storage systems to support the systems; and (4) the purchase of software to accommodate a large and diverse user group. The chemical research supported by this infrastructure runs the gamut of modern chemical research from fundamental studies of bonding to modeling of the reactivity of materials surfaces. The users of the infrastructure are diverse: high school students in North Carolina, young women scientists at Wellesley College and Spelman College, college students at Chicago State University, as well as the academic users at the University of Wisconsin.

Modern computer infrastructure allows chemists to do some experiments , virtually, without the need to use chemical reagents. In addition, checked against experiment, new, more accurate theoretical methods may be developed. In tandem with experiment, computations allow chemists to examine, in detail beyond that of current experimental methods, the molecular ballet that takes place in complicated chemical processes. The infrastructure made available with this grant will be used in teaching and training a broad range of young scientists in computational chemistry -- from high school, all the way through the post-graduate level.

Abstract
With this award from the Chemistry Research Instrumentation and Facilities: Departmental Multi-User Instrumentation program (CRIF:MU), Robert Hamers, Clark R. Landis and Shannan S. Stahl of the University of Wisconsin Department of Chemistry will acquire equipment to study solution-phase chemical reactions and catalytic processes performed at high pressures (50-3000 psig). The equipment includes reactors which allow monitoring reaction kinetics by infrared spectroscopy and attenuated total reflectance suitable for screening of reactions at high pressure. The equipment will be used to investigate at high pressures reactions with air-sensitive reagents or under anaerobic conditions including catalytic hydroformylation, polymerization and carbonylation reactions, and the study of oxidative reactions, high temperature chemistry and nitrous oxide chemistry.

High-pressure reactions have widespread significance in the chemical and pharmaceutical industries and include some of the most important large scale chemical processes: aerobic oxidation, hydrogenation and alkene polymerization. New reactions of this type and fundamental insights into existing reactions are critical to advance the field; however, such studies are complicated by the need to use specialized equipment that ensures safety. The equipment requested in this proposal will enable the discovery and mechanistic investigation of a wide range of chemical reactions under high-pressure. Students will be trained in the proper use of this equipment in their research and in course work improving their preparation for jobs in the chemical and pharmaceutical industries

With this award from the Chemistry Research Instrumentation and Facilities: Departmental Multi-User Instrumentation program (CRIF:MU), Professor Robert Hamers and colleagues from the University of Wisconsin Madison will acquire a a 400 MHz NMR spectrometer. The acquisition will advance research in areas of study such as (a) synthesis of bioactive substances, (b) synthesis and conformations of peptidic foldamers, (c) chemical synthesis of carbohydrate derivatives, (d) diazaphospholanes and catalytic asymmetric synthesis, (e) catalytic methods for selective aerobic oxidation of organic molecules, and (f) enantioselective C-H bond oxidation.

Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful tool used by chemists to identify unknown substances, to follow the progress of chemical reactions, to elucidate molecular structures, and to study the dynamics of interactions between molecules in solids and in solution. Access to state-of-the-art NMR spectrometers is essential for chemists who are carrying out frontier research and training students in modern research techniques. The results from these NMR studies will have an impact in synthetic organic and inorganic chemistry research at the University of Wisconsin. It will be used to train students in undergraduate laboratory courses. The instrument will be available to users at other undergraduate institutions in the Wisconsin system.

Non-technical Abstract
Diamond surfaces, including inexpensive thin-films and industrial-grade diamond powders, have the usual ability to emit electrons directly in to water and other liquids when illuminated with ultraviolet light. Electrons in water are a potent chemical reducing agent, able to induce very difficult chemical transformations such as the conversion of dinitrogen to ammonia and the reduction of carbon dioxide, but they have not been well studied because of the absence of convenient and efficient methods of preparation. The ability to directly emit electrons into water using inexpensive, reusable industrial-grade diamond provides a number of opportunities for inducing novel chemical transformations not accessible with conventional photochemical or electrochemical methods. With support of the Solid State and Materials Chemistry program in the Division of Materials Research, the objectives of this project are to understand the fundamental materials properties that influence electron emission from diamond into water, to use this understanding to create photoelectron emitters that function with good stability in water and other non-vacuum environments, and to identify whether diamond can be modified to allow it to easily emit electrons using visible light. If successful, the ability to easily produce electrons in water using visible or near-ultraviolet light would enable new, energy-efficient chemical transformation pathways not currently possible. Graduate students are being trained in state-of-the-art electrochemical methods and receive extensive professional development opportunities. The principal investigator and students are also mentoring undergraduate students and high school students on summer research projects as part of a broader effort to increase the number of students who have the opportunity to engage in state-of-the-art scientific research. The principal investigator and students are actively participating in several programs targeted specifically toward enhancing the diversity of the scientific workforce.

Technical Abstract
This renewal project is an outgrowth of research from the principal investigator demonstrating that diamond surfaces are able to emit electrons into water when illuminated with ultraviolet light, thereby allowing inexpensive diamond thin films and even industrial powders to be used as solid-state sources of electrons in liquids. While electron emission into vacuum has been studied previously, little is known about electron emission into water and other liquids. The primary goal of is project is to investigate the factors that control the photoemission of electrons from diamond into adjacent liquids, and to use this information to create photoelectron emitters that function with good stability and efficiency in non-vacuum environments. The project has three primary components. One is to understand how the electronic structure of the diamond-liquid interface influences the emission of electrons into adjacent liquids, by characterizing how variables such as the surface terminating layers, solution-phase ions, and externally applied potentials influence electron emission. A second is to determine whether metal-semiconductor junctions and plasmonic structures are able to increase the optical absorption of diamond and/or provide alternative pathways to exciting electrons to the conduction band. A third is to determine whether mid-gap states introduced by substitutional nitrogen or other dopants can provide a pathway to achieving electron emission using visible light. A wide range of experimental methods are being employed. X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopies are being used to characterize the chemical composition and electronic structure of diamond surfaces. Electrochemical methods including Mott-Schottky Analysis and Electrochemical Impedance Spectroscopy are being used to characterize the interfacial electronic structure and band alignments in aqueous media. Solvated electrons are being directly characterized using transient absorption spectroscopy and via chemical probes. Together, these methods are providing a comprehensive understanding of electron emission into liquids and providing insights into how to design interfaces that are most effective in enabling diamond to be used as a solid-state source of electrons in non-vacuum environments.

The Environmental Chemical Sciences (ECS) program of the Division of Chemistry will support the research program of Profs. Joel Pedersen and Robert Hamers of University of Wisconsin, Madison. Profs. Pedersen and Hamers and their students will investigate the interaction of well-defined peptides with metal oxide nanoparticles as a first step toward a deeper understanding of how nanoparticles interact with proteins. Titanium dioxide and aluminum oxide will be used as model systems for investigation. The specific aims of the study are: (i) employ discovery tools (phage-display methods) to identify binding motifs in short peptide sequences (heptapeptides) that lead to high affinity for nanoparticles of environmental relevance; (ii) investigate the thermodynamics and kinetics of peptide binding to TiO2 and Al2O3 nanoparticles, using both binding sequences identified via phage-display methods and simpler combinations of amino acids in tetrapeptides to elucidate binding rules; and (iii) identify the peptide functional groups that interact with the nanoparticles and understand the nature of peptide-surface bonds by combining experimental with computational methods.

The outcome of this research will be a fundamental understanding of the molecular level interactions that control the interactions of peptides with metal oxide nanoparticles. Knowledge of how factors such as peptide sequence, nanoparticle composition and structure, and solution composition affect peptide-nanoparticle interactions will provide insights into the physical and chemical processes that ultimately control the environmental safety and health impacts of nanomaterials. The project will provide outstanding educational opportunities for graduate and undergraduate students desiring to understand the interface between nanomaterials and biological systems.

Members of this Center for Chemical Innovation (CCI) will collaborate to understand, predict, and control the specific chemical and physical interactions between nanomaterial surfaces and living systems via a molecular level, chemistry-centered approach. Chemically stable nanoparticles having precisely controlled compositions, sizes, shapes, and surface functionalizations will be employed to investigate how they interact with lipid bilayers and with model organisms, toward the goal of understanding the factors influencing the routes by which nanoparticles enter biological systems. Experiments will use lipid bilayers as model systems for biological membranes, Shewanella oneidensis as a single-cell model, and Daphnia magna as a model whole organism. The resulting molecular level changes in gene expression and metabolism will be characterized and used as biomarkers to evaluate biological responses induced by different nanoparticles and surface functionalizations. These biological responses will in turn be used to inform the design and synthesis of nanoparticles having reduced adverse biological impacts. State-of-the-art analytical approaches, including nonlinear optical spectroscopies and genome sequencing tools, will be developed and used to characterize the interaction of functionalized nanoparticles with cells and simple organisms at the molecular level. These results will be informed by concurrent computational studies to provide fundamental insights into nanoparticle-biological interactions and to develop models with which to evaluate future nanomaterials.

The research of this CCI will ultimately contribute to the use of nanomaterials for societal benefit in a sustainable manner by leading to the development of nanomaterials with reduced environmental impact. The research will also provide enhanced training of graduate students in interdisciplinary science and the societal impact of nanotechnology. Graduate and undergraduate students will receive training in scientific and technological innovation that will help translate scientific results into economic benefit and other forms of societal impact. The CCI researchers will integrate their research on the sustainable nanotechnologies with educational and outreach activities to develop a program for informing and enhancing citizen engagement in nanotechnology and sustainability science using social media. CCI participants will also engage with teachers to develop K-12 and introductory level university science modules on the chemistry of safe and sustainable nanomaterials. Faculty and students of the CCI will engage with faculty and students at regional minority-serving institutions to increase participation from underrepresented groups via academic-year and summer research programs.

The Centers for Chemical Innovation (CCI) Program supports research centers that can address major, long-term fundamental chemical research challenges that have a high probability of both producing transformative research and leading to innovation. These Centers will attract broad scientific and public interest by sharing the results of their approach to this challenging question.

In this project, funded by the Macromolecular, Supramolecular, and Nanochemistry Program of the Chemistry Division, Prof. Robert Hamers of the University of Wisconsin-Madison and his students will integrate polymer chemistry with surface chemistry to make ultra-stable interfaces between metal oxide nanoparticles and molecular systems such as molecular photocatalysts and light-harvesting molecules. They will explore the synthesis and properties of functional "nano-skins" created on surfaces, using metal oxides such as TiO2 as model systems. In order to form robust layers, molecules bearing multiple reactive groups will be grafted to TiO2 surfaces; these will then be cross-linked to form two-dimensional surface nets in which each surface oligomer has many linkages to the surface. Electrochemically active species will then be linked to the net to form functional layers with novel electrochemical and photoelectrochemical properties. Fundamental properties such as electron transfer rates will be measured using surface-attached ferrocene groups. A variety of experimental measurements will be performed to characterize the chemical and physical properties of the layers in order to establish whether extensive lateral cross-linking within nanometer-thick molecular layers can lead to highly stable interfaces with novel electrochemical and photoelectrochemical properties.

This project will provide graduate students, undergraduate students, and junior scientists with state-of-the-art training in the techniques of surface chemistry and other career skills necessary to become scientific leaders. Students will learn techniques of chemical synthesis, characterization of surfaces, and a variety of electrochemical and photoelectrochemical measurement techniques. They will also receive training in oral and written communication, ethics, and leadership. The research will provide important fundamental insights into charge-transfer processes within and through molecular layers at surfaces and will help to establish design rules for how to fabricate highly stable interfaces between inorganic materials and organic-based molecular structures. Inorganic-organic hybrid structures are of great interest in a range of existing and emerging commercial technologies, and the ability to make water-stable interfaces between molecules and metal oxides such as TiO2 would have both commercial and societal impact in areas such as renewable energy. The project will also impact society by providing opportunities for educational and outreach activities with a diversity of outside groups.

This award from the Division of Chemistry at the National Science Foundation supports a Research Experiences for Undergraduate (REU) Site led by Professors Andrew Greenberg and Robert Hamers, both at the University of Wisconsin-Madison. The REU Site entitled "Chemistry of Materials for Renewable Energy" (CMRE REU) will fund 11 to 12 undergraduate students for a 10 week summer research experiences. Students will conduct individual research projects focused on chemical research applied to problems in renewable energy. The CMRE REU program will help students to strengthen their written and oral communication skills through proposal presentations, mid-experience report writing, and poster presentations. A novel aspect of the CMRE REU program is the encouragement of students to participate in an outreach experience with the Institute for Chemical Education's (ICE) "Fun with Chemistry Camp" to teach 5th-8th students about solar energy. To ensure proper mentoring and development of CMRE REU students, this project includes a mentoring workshop for graduate students, post-doctoral fellows, and faculty working directly with the REU Program.

Broader Impacts of the award involves young scientists who will be exposed to modern research methods and tools as part of their training. This REU site aims to provide cutting-edge research training in the chemical sciences to these students who might not otherwise have this opportunity. The research projects in chemistry will have an impact in the areas of energy and sustainability. The diverse student cohort participating in research at this site will be well-prepared for graduate school, and eventual employment as part of the country's technical workforce.

The Center for Sustainable Nanotechnology (CSN) enables fundamental studies of the specific molecular interactions expected to occur when the surfaces of engineered nanoparticles come into contact with biological interfaces and components. The chemical insight gained from molecular and mechanistic studies of nano-bio interactions is used to intentionally design nanomaterials that provide the desired technical functions while also minimizing potentially adverse consequences with the environment. CSN research leads to introduction of a new generation of safer nanomaterials that may impact multiple sectors of the economy including energy, transportation, electronics, food, and agriculture. The CSN prepares a new generation of scientific innovators by providing education and professional development opportunities focused on innovation, communication, leadership, and interdisciplinary scientific skills. CSN researchers actively encourage diversity within chemistry through CSN-run workshops on overcoming implicit bias, recruitment of graduate students and postdocs, and Center-sponsored research experiences for students and faculty from underrepresented groups as well as veteran undergraduates. CSN researchers encourage diversity in public engagement, develops and practices informal communication skills, and expands the highly successful sustainable-nano.com blog to include Spanish language content, K-12 activity materials, podcasts, and videos.

CSN integrates experiments with computation in three integrated research focus areas (RFAs). RFA1 develops new materials with precisely controlled structure and properties, molecular-level characterization tools such as advanced non-linear optical methods and sub-diffraction imaging, and novel computational methods spanning length scales from nanometers to millimeters. RFA2 uses the RFA1 tool kit to understand, control, and predict how nanomaterials attach to, penetrate, and alter cell surfaces using lipid bilayers as model systems for cell membranes. RFA3 determines the molecular processes by which pristine and environmentally transformed nanomaterials interact with living systems with diverse cellular chemistries, ranging from single cell to multi-cellular organisms. The integration of these three RFAs enables the Center to establish how nanomaterial properties and behavior impact biological outcomes. This knowledge leads to reliable predictions of biological responses to existing and future nanomaterials and guides the design and synthesis of safe, sustainable nanomaterials. In pursuing the project goals, the CSN puts particular emphasis on the synthesis, characterization, and molecular-level interactions initiated by complex, composite nanomaterials that are being used in emerging and future nano-enabled commercial technologies.

The Center for Sustainable Nanotechnology is funded as part of the Centers for Chemical Innovation (CCI) program.

The Division of Chemistry supports this workshop, entitled "Needs and Opportunities for Mid-Scale Instrumentation in Chemistry." It will be held on September 29-30, 2016 in Arlington, Virginia. Prof. Robert Hamers of the University of Wisconsin - Madison has assembled a team to organize the activities. This workshop brings together a diverse group of approximately 35 faculty from a broad range of institutions and geographic areas to discuss if research and education in the chemical sciences is limited by lack of access to instrumentation in the "mid-scale" range. These discussions focus on the regional and cyber enabled tools that could fill the needs of the chemistry community.

Goals of the workshop include: (1) identifying chemistry research areas where scientific progress is significantly limited or inhibited by lack of access to mid-scale instrumentation, (2) identifying research areas in which co-location of mid-scale instrumentation into regional instrumentation facilities would provide opportunities for transformative advances in chemistry research, (3) educating stakeholders on how mid-scale instrumentation could impact research in the chemical sciences, (4) preparing a workshop report summarizing the participants' views, (5) disseminating the report and findings to the broad scientific community via a publicly available, written report and a short video. The broader impacts are addressed by benefiting society in ways that maximize the effectiveness of public support of research and education in the chemical sciences.

The goal of this project is to explore novel approaches to chemical sensing and analysis. This approach based on a quantum-mechanical property of electrons known as spin. Diamond samples containing a special defect, the nitrogen vacancy (NV) center. One of the carbon atoms in the diamond is replaced by a nitrogen atom adjacent to a vacancy. Such samples emit light in a way that is altered by the presence of spins on nearby molecules. In this project, chemists, physicists, and electrical engineers are collaborating to make diamond samples with arrays of NV centers placed at very specific locations beneath diamond surfaces. They then investigate how the light emitted by the NV centers depends on the location and distance of molecules located immediately outside of the diamond sample. Because spin-based chemical sensors do not currently exist, this work has the potential to lead to new types of chemical sensors with very high sensitivity, possibly at the single-molecule level. If successful, spin-based chemical sensors would be useful in a wide range of chemical, environmental and biomedical applications. In addition to training graduate and undergraduate students in the quantum-based science, the researcher team is also engaged with outreach events and development of public-friendly podcast on quantum-based chemical detection.



The goal of the research is to explore fundamentally new approaches to detecting and measuring
molecular binding, cleavage, and dynamical motions at surfaces by exploiting the unique quantum mechanical properties of NV centers in diamond. The new sensing approach is based on characterizing
how electron spins of NV centers interact with spins present in molecules located nearby at the diamond-water interface. Nanolithographic patterning and ion implantation methods are being used to prepare samples containing arrays of NV centers, each of which can be probed and manipulated individually. Nanophotonic methods are being used to provide efficient ways of optically coupling light from individual NV centers to optical detectors. The diamond surfaces are being functionalized with molecules containing well defined spin probes that interact with the sub-surface NV centers in a manner that depends on the proximity between the spin probe and the NV centers. Researchers are using the resulting interactions between the spin of the molecules and the spin of the NV centers as a potentially novel approach to chemical sensing in which binding or release of molecules from surfaces is reported via spectroscopic changes in the NV centers.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

The NSF Center for Sustainable Nanotechnology (CSN) seeks to understand how nanoparticles, particles that are at least 10,000 times smaller than the width of a human hair, transform and interact in and with water and biological systems. Nanoparticles can vary in elemental composition, structure, and properties, which makes them useful for industries ranging from electronics, to batteries, to cosmetics. As nanoparticle use becomes more widespread, however, they are appearing in the environment. When nanoparticles are incorporated into biological systems they may induce unusual behavior that is beneficial or harmful, but is as of yet poorly understood. For instance, due to their small size, some nanoparticles can easily pass through some cell membranes. With very high surface area to volume ratios, nanoparticles can also be highly reactive, which may trigger chemical changes in the environment or to the nanoparticle itself. The CSN applies a "make, measure, model" strategy to develop new functional nanomaterials with increased sustainability and reduced biological impact. Expertise with synthetic methods, in situ analytical techniques, and computational methods is leveraged to understand, predict, and control nanoparticle properties and their chemical interactions with the environment and biological systems. The CSN addresses key knowledge gaps in the areas of nanoparticle properties which will result in better prediction of specific nanoparticle chemical properties and their biological interactions. This will ultimately serve the national interest by allowing for the design of more effective and more benign nanoparticles for many applications. Some of the systems the CSN investigates include: transition metal oxides and phosphates and two-dimensional quantum materials; gold, diamond and silicon based nanoparticles with defined organic and inorganic surface coatings; and as well as emerging nanoparticle compositions that exhibit fundamental new science and utility, such as those based on polymeric carbon dots, and nanovacancies in nanodiamond. This integrated, multi-institutional, and collaborative team involves researchers from the University of Wisconsin-Madison, University of Minnesota, Boston University, Georgia Institute of Technology, Johns Hopkins University, Augsburg University, University of California-Riverside, University of Wisconsin-Milwaukee, University of Iowa, University of Illinois at Urbana-Champaign, University of Maryland Baltimore County, Pacific Northwest National Laboratory, and the Connecticut Agricultural Experimental Station. The Center has a strong innovation component that involves the translation of research results into intellectual property, as well as other collaborations with several industrial partners. The CSN has an inclusive and transparent management approach that enables a positive Center climate and facilitates the integration of student learning across Center activities. Students broaden and deepen their technical expertise and grant writing through student laboratory exchanges and seed grant opportunities. The CSN places special emphasis on communication training. Example mechanisms to develop student communication skills are the popular Sustainable Nano Blog, http://sustainable-nano.com/, and the Spanish language-based Nano Sostenible Blog, http://nano-sostenible.com/. These are key components of the Center's informal science communication efforts, and students have ample opportunity to participate in these educational websites. Webinars on fostering technical innovation, internship opportunities, and opportunities to serve on the advisory board are mechanisms through which students further develop their professional skill sets. The CSN is committed to broadening participation efforts and incorporates summer research experiences for undergraduates and veterans, and relationships with minority-serving institutions, primarily undergraduate institutions, and community colleges as ways to address inclusivity. The strong focus on the CSN climate helps to ensure all participants feel welcomed, valued, and supported. Partnerships with the University of Puerto Rico at Cayey and Rio Piedras, the University of Texas Rio Grand Valley, Tuskegee University, and Georgia State University help to ensure that a diverse group of students can participate in the CSN where they develop not only the skills mentioned above, but also an understanding of the need to approach questions in chemistry with an awareness of sustainability, inclusivity, and interdisciplinarity. The CSN experience will prepare participants to make unique future contributions as members of the chemical workforce.

The CSN organizes their goals along four focus areas. One area focuses on establishing nanoparticle structure?function relationships. Chemical composition, size, shape, and organic or inorganic surface modifications are investigated with a combination of computational and experimental approaches. Transition metal oxides, nanoparticles comprised of earth-abundant elements, and nanoparticles that demonstrate novel properties or new utility are focal points. A second area of investigation centers on understanding nanoparticle transformations that occur in the environment and in biological media. Chemical changes in the nanoparticle core, the roles of inorganic and organic ions to impact nanoparticle stability, and surface structure are some of the areas explored. The third CSN thrust area explores nanoparticle coatings, referred to as coronas, formed by their exposure to the environment or biological systems at aqueous interfaces as a function of time. Analytical and computational approaches are developed to characterize and model the chemical nature and formation mechanisms of nanoparticle coronas. The fourth area is a chemistry-focused investigation of the physicochemical properties of nanoparticles and their interactions with biological systems. Nanoparticles with well-defined composition, structure, and surface chemistry are used to correlate, better understand, and predict nanoparticle physicochemical properties, spatial and temporal interactions at biological surfaces, and the direct or indirect effects on molecular interactions in cells and organisms. The CSN enriches the chemistry community by providing new tools for characterizing chemical processes at nanoparticle surfaces and by developing experimentally validated computational methods to predict the molecular-level behavior of complex materials in aqueous media. CSN participants are engaged in activities aimed at facilitating the creation and dissemination of knowledge, enhancing innovation and translation of research products and outcomes to the commercial sector, and providing unique education and training opportunities for students and postdoctoral researchers from diverse backgrounds.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.