Richard B. Kaner - US grants

This grant provides support under the Presidential Young Investigator Program. The project involves the application of inorganic chemistry to materials science with a focus on the synthesis and characterization of new solid state materials. Low temperature synthetic methods will be developed and exploited to produce kinetically stable solid state complexes which are inaccessible by other means. Target substances include new layered compounds such as metal sulfides which have interesting electronic and magnetic properties. Another goal of the project is to explore and characterize the effects of novel dopants on conducting polymers. For example, polyacetylene will be doped with heavy metals. Such dopants may change drastically such properties as magnetism, conductivity or charge storage capacity. Conducting polymers and layered metal sulfides will be investigated also as possible electrode materials for storage batteries. An important goal of this research is the development of a material to replace lithium in non-aqueous storage batteries.

A REU that would focus on the preparation and properties of electronic materials is established. Students would be involved each year in both academic year and summer research projects in the areas of semiconductor materials, optical materials, and electronic ceramics. The common focus of all the projects will be the development and understanding of materials with electrical or optical properties that are important for applications. Specific research projects include: (1) crystallization of amorphous ceramics, (2) infrared transmitting glass fibers, (3) mapping of epitaxial semiconductor materials, (4) synthesis and optical properties of doped sol-gel materials, (5) crystal growth of high conductivity oxides, optically active dyes-in-ceramic composites, and characterization of conducting polymers. Students for the academic year part of the program will be selected from a variety of undergraduate programs, including materials science, electrical engineering and chemistry. These students will receive academic year support for research activities and then be encouraged to continue as participants in on-going projects during the summer. Students for the summer part of the program will be recruited from a variety of high quality undergraduate institutions, such as Harvey Mudd and the Pomona Colleges, which are not able to provide a graduate-level research environment. A summer seminar series will be conducted in which students can present their work and interact professionally with graduate students and faculty in a research environment. Several of the students will be selected each year to present their work at national meetings.

9315914 Kaner In this research, metathesis reactions are used to prepare refractory and electronically and magnetically important materials. These reactions are effective for the rapid synthesis (< 2 s) of a large variety of materials. Targeted systems include refractory main group borides, carbides, nitrides and phosphides and conductive refractory transition metal nitrides and phosphides and magnetic rare earth phosphides. Additionally, special efforts will be made to refine methods for the preparation of metastable high temperature compounds. Further studies will examine the processing of ceramic materials, specifically studying the effects of varying crystallinity and particle size on the densification and mechanical properties of hot-pressed samples. % % % Direct solid-state reactions often are complicated by the need for long reaction times at elevated temperatures. Metathesis reactions allow the preparation of materials in seconds. In this research, metathesis reactions are used to prepare refractory and electronically and magnetically important materials. The effects of varying crystallinity and particle size on the densification and mechanical properties of hot-pressed samples will be explored. ***

1 9704964 Kaner Highly exothermic chemical exchange (metathesis) reactions in the solid-state can be designed to lead rapidly to materials that are otherwise difficult to form. This project will explore the application of pressure to open a new parameter space for the synthesis of high pressure phases which inaccessible under ambient conditions. This approach to solid state metathesis reactions will provide a new synthetic method for forming high quality solid solutions, and for controlling crystallite size, and the important questions explored in this research will have advance considerably the area of chemical processing. %%% The classes of materials to be investigated are of considerable potential technological importance and include crystal size and photoluminescence studies on gallium nitride, and cubic boron nitride, the second hardest materials known after diamond. Methods for forming diamond and substituted carbon materials will also be tested. ***

The main objective of this project is to develop new routes to important materials by designing rapid solid-state methasis (exchanged) reactions that use appropriate additives such as ammonium chloride to control temperature and pressure. Systems to be synthesized include indium nitride and its solid solutions with gallium nitride and aluminum nitride, which are expected to luminesce across the entire visible range form red to violet and beyond. Also, cubic molybdenum nitride, a hydrodesulfurizaiton catalyst, will be synthesized, and new routes of carbon nanotubes will be explored and optimized through the control of reaction temperature where a computer program will be developed to determine maximum reaction temperatures based on thermodynamic data.
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This project is aimed at the control of pressure and temperature in metathesis reactions for the synthesis of a number of industrially relevant materials such as carbon nanotubes, encapsulated metals, silicon nitride, cubic boron nitride and molybdenum nitride that are difficult to prepare. These materials all have interesting optical, mechanical or catalytic properties. The students involved in this research will learn synthetic and characterization techniques, and they will have an opportunity to collaborate with national laboratory and industrial scientists. This unique integration of research and education will help to make these students highly competitive in the job market

The Materials Creation Training Program (MCTP) at UCLA will train scientists to be leaders in the design, synthesis, and production of new materials for electronic, computer, communication, and nanoscale devices. The training and mentoring faculty come from departments in Physical Sciences (Physics and Astronomy, Chemistry and Biochemistry) and Engineering (Mechanical and Aerospace, Chemical, and Electrical Engineering, and Materials Science). All are associates of the UCLA Exotic Materials Institute (EMI), which will administer the MCTP. Many are also members of the California NanoSystems Institute (CNSI) - a state-supported venture that was created in 2001 to provide facilities and resources for materials and medical nanoscience. This resource will be available for training and research of MCTP Fellows. The MCTP unites a broad range of molecular and materials architects, synthetic chemists, and device fabricators, at UCLA and at partner industrial and national laboratories. MCTP Fellows are supported for two years of their graduate careers, during which they will work in teams with UCLA and off-campus scientist partners using state-of-the-art instrumentation and computational resources. Novel training aspects will include a new graduate course involving all aspects of materials and molecular design, synthesis, testing, and modification of materials, device fabrication and testing, and demonstration and marketing aspects of practical devices. This course will deal with science issues beyond the laboratory and will develop researchers versed in the importance of understanding materials properties across length scales, from molecular to macroscopic. Each MCTP Fellow will spend several months or more at an industrial or national laboratory partner site. Research projects will include the design and synthesis of new molecules, the transformation of these into molecular solids and polymers, the formation of new inorganic and organic/information composites, and the development of devices based on these new materials. Fellows will be selected for excellence and diversity. The new graduate program will be evaluated on a yearly basis by a board including university, industrial, and government representatives. Community outreach activities will emphasize the importance and potential of scientific research and attractiveness of graduate education in science. The Materials (MCTP), Bioinformatics, and Neuroengineering IGERTs at UCLA constitute a new graduate educational paradigm, emphasizing multidisciplinary research encompassing life and physical sciences, as well as computer science and engineering.

IGERT is an NSF-wide program intended to meet the challenges of educating Ph.D. scientists and engineers with the multidisciplinary backgrounds and the technical, professional, and personal skills needed for the career demands of the future. The program is intended to catalyze a cultural change in graduate education by establishing new, innovative models for graduate education and training in a fertile environment for collaborative research that transcends traditional disciplinary boundaries. In the fourth year of the program, awards are being made to twenty-two institutions for programs that collectively span all areas of science and engineering supported by NSF. The intellectual foci of this specific award reside in the Directorates for Mathematical and Physical Sciences; Engineering; and Education and Human Resources.

TECHNICAL SUMMARY: The intersection between the emerging fields of conducting polymers and nanoscience offers exciting opportunities to make very sensitive sensors, high-density memory storage devices and artificial muscles. Our newly developed process for making ultra-small diameter fibers of the conducting polymer polyaniline provides the basis for this project. The nanofibers will be decorated with functional molecules, nanoparticles and polymers at the nanometer scale. Coating processes will be developed to form uniform nanofiber films. These films will be used to make sensors that exploit the rapid change in electrical conductivity possible with conducting polymer nanofibers. Suitable additives will be dispersed into polyaniline nanofiber networks to tailor the interaction between nanofibers and analytes, greatly enhancing their sensitivity and selectivity for sensing toxic chemicals. Non-volatile molecular memory devices that can write, read, store and erase information based on polyaniline nanofibers decorated with metal nanoparticles will be explored. An ordinary camera flash has been found to cause a film of nanofibers to weld together. This process, called flash welding, will be used to weld conventional polymers together, to create composites between conducting and traditional polymers, to form patterned structures and to create "artificial muscles". Artificial muscles are a type of mechanical actuator that responds to a chemical or electrochemical stimulus by expanding or contracting. Disseminating information to the public and effective training of students at all levels (K-12, undergraduate, graduate and postdoctoral) are the most important ways in which this proposal will have broad impact. Our plan is to have students learn every aspect of developing conducting polymer nanofibers from synthesis and characterization to building and testing devices. Our interdisciplinary research involving scientists and engineers from not only UCLA but also industry, the national labs and international collaborations will provide our students with exceptional educational opportunities that will serve them well in their future endeavors. All students and faculty involved in this project will bring their enthusiasm for science to the public through outreach activities.


NON-TECHNICAL SUMMARY: The intersection between the emerging fields of conducting polymers and nanoscience offers exciting opportunities to make very sensitive sensors, high-density memory storage devices and artificial muscles. Our newly developed process for making ultra-small diameter fibers of the conducting polymer polyaniline provides the basis for this project. Sensors will be constructed that exploit the rapid change in electrical conductivity possible with conducting polymer nanofibers. Additives will be dispersed into the polyaniline nanofiber networks to enhance their selectivity for sensing toxic chemicals. Non-volatile molecular memory devices that can write, read, store and erase information based on polyaniline nanofibers decorated with metal nanoparticles will be explored. An ordinary camera flash has been found to cause a film of nanofibers to weld together. This process, called flash welding, will be used to weld conventional polymers together, to create composites between conducting and traditional polymers, to form patterned structures and to create artificial muscles.
Disseminating information to the public and effective training of students at all levels (K-12, undergraduate, graduate and postdoctoral) are the most important ways in which this proposal will have broad impact. Our plan is to have students learn every aspect of developing conducting polymer nanofibers from synthesis and characterization to building and testing devices. Our interdisciplinary research involving scientists and engineers from not only UCLA but also industry, the national labs and international collaborations will provide our students with exceptional educational opportunities that will serve them well in their future endeavors. All students and faculty involved in this project will bring their enthusiasm for science to the public through outreach activities.

Solid-state metathesis (exchange) reactions can enable the rapid synthesis of materials that are difficult to prepare by conventional methods. This project will explore new routes to high surface area titanium nitride, ultra-incompressible transition metal diborides and structural intermetallics. Since metathesis reactions produce crystalline materials within seconds due to growth in a molten salt matrix, crystallite size and surface area can be controlled with appropriate additives. Titanium nitride, an electrically conductive refractory ceramic used in electrodes for super-capacitors, will be synthesized to test this hypothesis. A new class of ultra-incompressible, hard materials will be created by combining high electron density metals, such as osmium, with small covalently bonded main group elements such as boron. Genetic algorithms will be developed that enable metathesis reactions to be optimized while running a minimum number of reactions. Graduate students will learn synthesis, characterization and measuring of physical properties through collaborations both within the chemistry department and with materials science, mechanical engineering and industrial partners. Undergraduates, including those from under-represented groups, will assist the graduate students in research, thereby enhancing the future graduate student pool in materials chemistry. A new course is being developed entitled "It's a Material World" that will enable both science and non-science majors to gain a better understanding of the importance of materials in the real world. The curriculum developed for this course will then be reconfigured and used to reach a broader audience from grade school children through alumni.



The modern world is based on developing new and improved materials such as doped silicon to run computers and synthetic diamond for cutting through rock to build roads. Solid-state metathesis (exchange) reactions can enable the rapid synthesis of materials that are difficult to prepare by conventional methods. Since metathesis reactions produce crystalline materials within seconds, due to growth in a molten salt matrix, the size of the crystal grains and their surface area can be controlled with appropriate additives. Titanium nitride, which is an electrically conductive high temperature ceramic used in electrodes for rapidly chargeable and dischargeable energy storage devices known as super-capacitors, will be synthesized to test this hypothesis. A new class of ultra-incompressible, hard materials will be created by combining high density metals, such as osmium, with small main group elements such as boron. Computer codes, known as genetic algorithms, will be developed that enable metathesis reactions to be optimized while running a minimum number of reactions. Graduate students will learn synthesis, characterization and measuring of physical properties through collaborations both within the chemistry department and with materials science, mechanical engineering and industrial partners. Undergraduates, including those from under-represented groups, will assist the graduate students in research, thereby enhancing the future graduate student pool in materials chemistry.

This Integrative Graduate Education and Research Traineeship (IGERT) renewal award supports the further development of the UCLA Materials Creation Training Program (MCTP). The MCTP enables trainees to master a specific discipline, while being immersed in the collaborative scientific cultures characteristic of careers of the future, as emphasized in the National Nanotechnology Initiative. Supported by the MCTP in their second and third years, students are trained in all aspects of the design, synthesis, and characterization of novel molecules and assemblies, and in the fabrication, characterization and marketing of devices based on these materials, including biosensors and biomaterials. The MCTP engages graduate students and faculty from Chemistry & Biochemistry, Physics, and the Chemical, Electrical, Mechanical and Aerospace, and Materials Science Engineering departments at UCLA. The trainees experience training in cross-disciplinary laboratories, classes and seminars in addition to their disciplinary graduate training and research. Key components of the program include: a co-advisor from a complementary discipline; an external internship at a company, government lab or abroad; participation in annual symposia, and training in the responsible conduct of research. To institutionalize the program, the MCTP courses will serve as the nucleus of new academic minors and a new interdepartmental PhD program in NanoScience and NanoTechnology. The California NanoSystems Institute (CNSI) will phase in support for MCTP fellowships and administration of these academic programs. New programs to enhance diversity and international research experiences of the trainees include a collaborative program with the UCLA Alliance for Graduate Education and the Professoriate, and a new MCTP Master Fellows Bridge Program in partnership with Cal State Los Angeles (CSULA) to enhance the training of Master's degree students at CSULA and increase the number of underrepresented students enrolling in STEM doctoral programs. The MCTP will continue its K-12 education and outreach partnership with the CNSI and Center X in the UCLA Graduate School of Education, through which the MCTP trainees work with teachers and high school students at underserved schools in the Los Angeles Unified School District, providing hands-on experience with modern techniques, devices and materials. IGERT is an NSF-wide program intended to meet the challenges of educating U.S. Ph.D. scientists and engineers with the interdisciplinary background, deep knowledge in a chosen discipline, and the technical, professional, and personal skills needed for the career demands of the future. The program is intended to catalyze a cultural change in graduate education by establishing innovative new models for graduate education and training in a fertile environment for collaborative research that transcends traditional disciplinary boundaries.

This award to University of California-Los Angeles by the Solid State Materials Chemistry program in the Division of Materials Research is to grow single crystals of Rhenium diboride (ReB2) and to measure the physical properties of ReB2 as a function of crystallographic orientation. The hardness of ReB2 will then be enhanced by forming solid solutions and synthesizing dense nanocrystalline composites. In other studies, rhenium will be replaced completely with other transition metals such as Titanium while maintaining the ReB2 structure type. These approaches may enable to construct new ultra-incompressible, superhard materials using less expensive metals. The search for new ultra-incompressible, superhard materials holds both scientific and practical interest. The proposed design plan is to combine high valence electron density transition metals with small main group elements to replace the weak metallic bonds with strong covalent bonds. Using this approach, it is possible to convert relatively soft rhenium metal into an extremely hard Rhenium diboride, which has many exciting physical properties including low incompressibility, high hardness, and the ability to scratch diamond. Synthesis and testing of coatings will be carried out in conjunction with a local company that specializes in developing ultra-hard coatings. Hardness, fracture toughness and Young?s modulus will be determined by indentation techniques. Radial diffraction experiments will also be used to determine the mechanical properties of these materials. As part of this project, an outreach program be developed entitled ?It?s a Material World? that is suitable for both undergraduate students and general audiences. This course will be offered to UCLA undergraduates each year to enhance their interest in materials chemistry. In addition, materials developed for this course will be used for interactive seminars with both high school and middle school students.

The main thrust of the proposal is to synthesize crystals of Rhenium Diboride and other structurally related borides of transition metals such as Titanium. Using this approach, it is possible to convert relatively soft metals into extremely hard materials, which are harder than diamond. The search for new ultra-incompressible, superhard materials holds both scientific and practical interest in a number of applications. An outreach program will be developed entitled ?It?s a Material World? that is suitable for both undergraduate students at the campus and general audiences. This program offered to non-science undergraduate students is to enhance their interest in science in general and materials science in particular. In addition, materials developed for this course will be used for interactive seminars with both high school and middle school students.

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Ju
This proposal is concerned with recovering exhaust waste heat to improve the efficiency of vehicles. An interdisciplinary team of mechanical engineers, a material scientist, and a chemist is assembled to tackle this problem by synthesizing novel nanostructured silicides with improved thermoelectric figures of merit.

Intellectual Merit: The proposed research on nanocomposites and related interfaces will help establish a scientific and engineering foundation for robust and flexible thermomechanical design of thermoelectric systems subjected to thermal cycling and vibration. The PIs will develop metal-matrix composites with tailorable coefficients of thermal exapansion (CTEs) using a filler material with an isotropic negative thermal expansion (NTE). NTE fillers, such as ZrW2O8 powders, can effectively offset the high CTE of the metal phase without significantly degrading the electrical and thermal conductivity. These nanocomposites may be used as electrodes or as interfacial layers for creating segmented thermoeletric elements. Thermomechanical models of TE modules will be developed to guide the design of the nanocomposites, including those with functionally graded compositions. Nanocomposites based on different metals, such as Ag, Al, and Ni, will be synthesized and their thermal and thermomechanical properties will be experimentally characterized. Methods to produce reliable electrical, thermal, and mechanical bonds with TE materials will also be developed.

Broader Impact: The proposed research is designed to maximize the potential for large-scale implementation in vehicle exhaust heat recovery and other related engineering applications. The new material synthesis and bonding methods that will be developed is considered to facilitate economic fabrication of durable TE devices. Another component included in the plan is the training of students in interdisciplinary research whereby fundamental science is coupled to advanced engineering. The PI and graduate students will participate in outreach programs to bring science and engineering to pupils in grades K-12 through summer research programs hosted at UCLA.

TECHNICAL SUMMARY
Transition metal borides have attracted increasing interest due to their physical properties that combine high hardness and electrical conductivity with straightforward ambient pressure synthesis. If designed properly, superhard metallic borides could lead to improved cutting tools and wear-resistant coatings. Rhenium diboride (ReB2) is a good example of this new and growing class of superhard, metallic borides. With support from the Solid State and Materials Chemistry Program, the possibility of improving on the properties of ReB2 by making solid solutions of ReB2 with other transition metals to activate dislocation-pinning mechanisms that could create harder materials will be explored. Less expensive transition metal borides will be synthesized by replacing rhenium with the relatively inexpensive transition metal tungsten. By completely replacing Re with W and increasing the boron concentration, another interesting boride, tungsten tetraboride (WB4), can be made which appears to have comparable hardness to ReB2. After characterizing its physical properties including micro- and nano-indentation, ambient and high pressure X-ray diffraction and resonant ultrasound spectroscopy of both polycrystalline and single crystalline WB4, its structure will be reexamined using neutron diffraction. This powerful tool should enable the determination of the exact positions of the boron atoms in the unit cell, something that is currently not known. This should provide better insight into the bulk modulus, high hardness and other properties of WB4. Making solid solutions of WB4 with other transition metal elements such as Ta, Mo, Cr and Mn, will be carried out in order to potentially increase hardness and impart improved corrosion protection, thermal stability and fracture toughness. A long-term goal of this project is to explore the feasibility of using these superhard, metallic borides for cutting tools. By taking advantage of their electrical conductivity, desired shapes will be cut using electric discharge machining (EDM). Cutting tool inserts will be made by EDM, and properties such as wear resistance will be tested. Coatings will be developed and friction tests carried out. Broader impact of this project will be achieved by engaging undergraduates in the research and providing high school students and teachers with lectures and demonstrations of materials and their applications.
NON-TECHNICAL SUMMARY
The search for new superhard metals holds both great scientific and practical interest. Scientifically, an understanding of how and why materials known for their malleability can be turned into ultra-incompressible, superhard compounds will be gained. Practically, these metallic materials, no matter how hard, can be cut into precise shapes using a readily available process known as electric discharge machining. This will enable the exploration of their possible use for milling, sawing and drilling. Electric discharge machining will be used to turn these new materials into tools that will be tested for their ability to cut ferrous metals. Scratch resistant coatings with low friction surfaces will also be developed and tested. Broader impact of these projects will be achieved by engaging undergraduates in the research and providing high school students and teachers with lectures and demonstrations of materials and their applications.

CBET-1337065
Eric M.V. Hoek
University of California, Los Angeles

The health issues surrounding the diminishing supply of global freshwater are well known and new ecological, agricultural, and geopolitical implications are now being recognized. It is even predicted that developed nations such as the United States will be considered "water-stressed" by 2025. Currently, polymeric membrane technology is the state-of-the-art method to produce clean, potable water from unconventional sources such as seawater or wastewater. The feed water is pumped through the highly selective plastic films and pollutants are rejected: however, the membranes quickly foul due to accumulation of rejected pollutants on the membrane surface and/or within membrane pores. A significant amount of energy and water are lost to membrane cleaning with frequent permeate backwashes and periodically cleaning with harsh chemicals that degrade membrane polymers resulting in premature replacement. The aim of this project is to develop fouling-resistant membranes to reduce increased energy demand and operating costs associated with water treatment membranes by modifying the surface of the membranes with compounds that repel or deactivate fouling materials. Membrane surface modifications have been demonstrated in past, but most have required exotic reaction conditions, long reaction times, and/or expensive reagents that limited their commercial application. The project team recently developed a novel surface modification chemistry that covalently attaches anti-adhesion and anti-bacterial compounds to the surface of polymeric membranes. The reaction is performed in water at room temperature and atmospheric pressure while using inexpensive reagents and environmentally benign processing conditions. Preliminary results demonstrate that commercial RO and UF membranes are easily modified by a variety of compounds. The membranes retain their basic separation performance characteristics, but have dramatically altered surfaces. The result is that by altering modification chemistry and conditions we can modulate bacterial adhesion to RO membranes. To determine optimal anti-fouling compound properties, several compounds will be synthesized and screened for anti-fouling behavior using High-Throughput Screening protocols previously developed by the project team. The compounds will have varying electrostatic charge, molecular weight, and anti-bacterial functionality. Commercial membranes will be modified with the new surface chemistries and evaluated for their resultant productivity, pollutant rejection, improved fouling-resistance and ease of cleaning.

This project will develop new anti-fouling membranes materials for large-scale water treatment. By modifying membrane surfaces with different properties, optimal surface properties will be ascertained to help understand the mechanisms that contribute to surface fouling and biofilm formation in aqueous environments. The result of this project will provide an effective way to produce anti-fouling membranes on a large scale to reduce energy demand and operating costs associated with converting seawater or wastewater into clean, usable water.

With this award from the Major Research Instrumentation Program (MRI) and support from the Chemistry Research Instrumentation Program (CRIF), Professor Miguel Garcia-Garibay from University of California at Los Angeles (UCLA) and colleagues Louis Bouchard, Richard Kaner, Alexander Spokoyny and Jeffery Zink aquired a 600 MHz NMR spectrometer with solid state capabilities. This spectrometer allows research in a variety of fields such as those that accelerate chemical reactions of significant economic importance, as well as those that allow study of biologically relevant species. In general, Nuclear Magnetic Resonance (NMR) spectroscopy is one of the most powerful tools available to chemists for the elucidation of the structure of molecules. It is used to identify unknown substances, to characterize specific arrangements of atoms within molecules, and to study the dynamics of interactions between molecules in solution or in the solid state. Access to state-of-the-art NMR spectrometers is essential to chemists who are carrying out frontier research. The results from these NMR studies impact synthetic organic/inorganic chemistry, materials chemistry and biochemistry. This instrument is an integral part of teaching as well as research performed by undergraduate students at the University of California at Los Angeles. This new high-field NMR spectrometer, to be placed in an open-access, shared instrumentation facility, enriches the research experiences of the many graduate students, postdoctoral fellows, and undergraduate researchers who pursue research projects utilizing solid-state NMR. The research supported by the use of solid-state NMR is very broad-based, encompassing materials characterization, chemical synthesis, toxicology, and instrumental analysis.

The award is aimed at enhancing research and education at all levels, especially in areas such as: (a) amphidynamic crystalline materials based on inertial rotors and dipolar arrays; (b) in situ imaging of chemically reacting flows; (c) high throughput screening of anti-fouling and anti-bacterial coating films; (d) naturally occurring proteins and other biomolecules that act as robust and generalizable dispersing agents for metal oxide nanoparticles; (e) cationic surface coatings on non-toxic nanoparticles that enhance cellular uptake especially those where the toxicity increases with the molecular weight on the polymer coating; (f) the unexpected effect of the aspect ratio of nanorods on cellular uptake; (g) cerium dioxide nanowires of precisely controlled length that can be synthesized using hydrothermal methods; (h) metallic surface states in thalium compounds; (i) robust thin films for desalination; (j) polymers produced from boron-rich clusters; and (k) nanoparticle-based machines for trapping and releasing molecules from mesopores.

Non-Technical Abstract
The creation of, and mastery over, ever-harder materials is an endeavor at least as old as chemistry itself. The importance of hard materials to tools, technology, and the societies they sustain is so self-evident that it is common archaeological practice to name pre-historic human eras by the tooling resources employed, i.e. Stone Age, Bronze Age, etc. In the modern age, superhard materials are needed for high-performance cutting tools, especially for preventing tool damage when cutting advanced ceramics and superalloys. Considering the contributions of the machining industries to the global economy, it is clear that a new generation of cutting tools could have a significant impact worldwide; the world market for superhard materials is projected to reach over $20 billion within the next 5 years. Unfortunately, very few superhard materials exist and those that do (such as diamond) need to be synthesized under extreme pressure and heat, thus making them too expensive for many applications. With support from the Solid State and Materials Chemistry program in the Division of Materials Research, the research team is developing the next generation of superhard materials than can be produced at ambient pressure - superhard metal borides. Training the next generation of materials chemists and bringing the excitement of this project to the general public will provide broader impact. The Principal Investigator serves as the faculty advisor to the Student Members of the American Chemical Society at UCLA. This position has been successfully used to reach many middle and high school students through visits to their schools, fostering a love for chemistry for both undergraduates and K-12 students. The co-Principal Investigator is actively developing new ways to teach science with high school teachers through her position as the Director of Outreach for the California NanoSystems Institute. Each graduate student involved in this proposal helps with outreach projects and mentors undergraduates. The undergraduates will assist the graduate students in research, thereby increasing the future graduate student pool in materials chemistry.

Technical Abstract
Ten years ago, the Principal Investigators suggested that new superhard materials that could be synthesized at atmospheric pressure (unlike diamond or cubic BN) could be compositionally designed by incorporating covalent bonding into high valence electron density metals. The covalent bonds prevent shear and the electron density adds incompressibility. Transition metal borides exemplify these parameters by providing high valence electron density, multiple boron-boron covalent bonds, and unique crystallographic structures. This idea was first demonstrated with osmium diboride (incompressible), and then with rhenium diboride and tungsten tetraboride (both of which are superhard and incompressible). With support from the Solid State and Materials Chemistry program in the Division of Materials Research, the research team refines and expands on these materials by focusing on structure and bonding motifs. The superhard design toolkit can be enlarged by studying the mechanical properties of new tungsten tetraboride solid-solutions to form dodecaboride-type structures, increasing electron density through doping with iron, and by examining the lower borides of tungsten, which complement the 3-D boron network of tungsten tetraboride by containing 0-D, 1-D, and 2-D boron structures. This family of compounds serves as a model system for understanding how the nature of B-B and B-metal bonds affect hardness. Each composition can be studied using high-pressure radial diffraction to obtain lattice plane specific information about failure and slip. The eventual goal is the development of a third design parameter to explicitly elucidate the structures and bonding motifs that should most improve macroscopic mechanical properties based on microscopic bonding. In this way, the Principal Investigators hope to uncover additional fundamental design rules that can be used to rationally synthesize new members of an increasingly complex family of ultra-hard yet easy to synthesize materials.

The Planning Grants for Engineering Research Centers competition was run as a pilot solicitation within the ERC program. Planning grants are not required as part of the full ERC competition, but intended to build capacity among teams to plan for convergent, center-scale engineering research. This planning grant will develop well-formulated plans for a future Engineering Research Center for Carbon Dioxide Utilization by: (a) enabling face? to-face interactions among diverse academic experts and industry leaders at planning workshops, (b) building industrial alliances, and (c) achieving deeper and more closely integrated convergence across disciplines. The in-person workshops will establish cohesive/coordinated interactions among team members, both at a personal and professional level, thereby enabling organic collaborations within and across disciplinary domains to fulfill a unified vision and goals. The provision of dedicated planning resources will create momentum within the team, helping to create an ascending and compelling agenda. This will cohere and motivate the team to develop grand solutions to the grand challenges of C02 management.

This project has the potential to advance knowledge in (a) molecular-level interactions of CO2 with sorbents, membranes, and catalysts to exploit attributes such as defects, disorder, interfaces, and heterogeneity to control and enhance reaction rates, and (b) how cooperative phenomena (e.g., based on structural transitions) can reduce the extrinsic energy needs of CO2 capture and conversion processes, thereby improving process efficiencies. These advances will allow exploitation of complex electronic and atomic correlations to design and control materials, and the fabrication of hierarchical structures toward a common goal: the cost-effective capture and conversion of CO2.

The project will allow for upcycling (beneficial utilization) of CO2 emissions at the gigaton scale and will position the U.S. as the world leader in this emerging domain. The institution of such disruptive offtake pathways for CO2 is a prerequisite for empowering the creation and success of the carbon-to-value economy and retarding the rate at which the climate is changing.

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.

NON-TECHNICAL SUMMARY:

Mechanical hardness is an important property used to determine the applications of materials in the machining and manufacturing industries. Due to the extensive use of hard materials as cutting tools and abrasives, the demand for superhard materials has been steadily increasing. The best-known superhard material ? diamond ? is not effective at cutting and drilling steel due to its poor thermal stability in air and its tendency to react with the iron in the steel it is trying to cut. Therefore, there is great interest in finding alternatives to traditional superhard materials. These are needed in the construction, automotive, and other industries to replace costly and low performing traditional hard materials like tungsten carbide. To address these issues, the Principal Investigators (PIs) are designing a new generation of superhard materials that will provide greatly increased hardness and the ability to cut steels and other materials at lower cost. Inspired by the unique properties of natural diamond, the Principal Investigators have focused on creating networks with similar properties in other compounds, focusing on mixtures of electron-rich metals and boron. The novel superhard materials are synthesized at ambient pressure and characterization will be conducted to understand the correlation between material structure and hardness. The educational efforts of the PIs, which address the needs of students ranging from elementary school to college undergraduates, include course development, teacher workshops for elementary, middle, and high schools in the greater Los Angeles area, and school outreach visits. Workforce development occurs through the training of graduate students, who also assist with outreach programs and mentor UCLA undergraduate students through research. This project is supported by the Solid State and Materials Chemistry program within the Division of Materials Research.

TECHNICAL SUMMARY:

Hardness is a physical phenomenon dependent on both the chemical bond strength and grain structure of a material. An understanding of how to design new superhard materials thus requires sufficient mechanistic insight and control of both bonding and grain morphology. To address this challenge, the Principal Investigators (PIs) are combining the synthesis of a wide range of transition metal boride systems with high-pressure studies to obtain lattice-specific information about plastic deformations in a broad range of bulk and nanoscale materials. These metal boride structures consist of high valence electron density metals, combined with multiple short boron-boron bonds, providing a highly covalent bonding network that is resistant to slip and dislocations, combined with high electrostatic repulsion that resists bond compression. The goal of the proposed work, supported by the Solid State and Materials Chemistry program within the Division of Materials Research, is to synthetically control both grain size and morphology. In bulk materials, this is being accomplished through the decomposition of metastable dodecaboride phases in the WB4 system and through precipitation of secondary phases in the ReB2 system. Additionally, molten salt methods are being used to develop nano grain-sized metal borides such as nano-ReB2 and nano-WB4. These synthetic approaches thus aim to enhance extrinsic hardness in both bulk and nano-sized materials. Materials are being analyzed through Vickers hardness testing and high-pressure experiments in diamond anvil cells. With an understanding of the coupled effects of bonding and grain morphology, the research team aims to systematically tune nanostructured materials and advance the next generation of superhard metal borides. The broader impacts of the work lie in workforce development through the training of graduate students, in the extensive outreach efforts of the PIs, which address the needs of students ranging from elementary school to college undergraduates, and in the significant potential for impact on the commercial cutting, drilling and machining industries.

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.