SusChEM: Catalytically Active Earth Abundant Materials with Unique Structure and Properties

Colorado School Of Mines, Golden CO

Investigators

Abstract

Catalytically Active Earth Abundant Materials with Unique Structure and Property Many of the metals and materials used in catalysis are rare and expensive. However, as energy needs increase and the traditional catalytically-active noble metals become scarce, it is paramount that novel materials are discovered to replace them and the capabilities of these new materials are explored. The team, consisting of Profs. Trewyn, Pylypenko, and Richards, is investigating the development of nanostructures composed of earth abundant materials entrapped in high surface area, porous materials with unique shapes and chemistry, and are developing a fundamental understanding of factors that influence reactions integral to biomass upgrading to higher value products, such as fuels and chemical feedstocks for industrial use. The team is focused on the chemistry of both catalytically active nanoparticles and metal atoms distributed in the porous supports. They are studying the conversion process of metals and metal oxides to metal carbides and metal nitrides which may possess unique catalytic properties that closely mimic those of the noble metals currently used for many of the catalytic processes important to our global energy and chemical needs. This collaborative effort leverages a strong and unique ability to study the properties of the active species distributed at the atomic level using transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy (XPS) under reaction conditions. Importantly, this team brings expertise in material sciences, material characterization, inorganic and analytical chemistry and catalysis. The catalytic activity of these newly synthesized catalysts are tested against reactions frequently observed in upgrading biomass so as to develop important structure/activity relationships. The team attracts undergraduate and graduate students from many disciplines and walks of life to participate in research. The group hosts and mentors high school students to conduct research in their laboratories along with traveling to K-12 schools to demonstrate the power of science. Finally, the team participates in organizing several conferences in these research areas, all emphasizing student involvement. In this research project, Drs. Trewyn, Pylypenko, and Richards, all of the Colorado School of Mines, are supported by the Macromolecular, Supramolecular and Nanochemistry (MSN) Program to develop and study nanostructures of earth abundant elements with enhanced catalytic activity while manipulating the density and stability of the active sites on high surface area, porous supports. Working as a highly complimentary team, they are evolving the synthesis of supported metal carbides and metal nitrides by converting metal and metal oxide nanoparticles embedded in mesoporous silica through exposure to methane (carbon) and ammonia (nitrogen) at elevated thermal and pressurized conditions. Atomically distributed metal carbides and metal nitrides are presently produced by post-synthetically treating mixed metal oxides under similar conditions. The group is investigating the properties of active species that give them catalytic properties similar to the very active, but rare, Group 10 metals. In addition to a strong synthetic background, the team uses their expertise in in-situ/operando characterization techniques, including x-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM), which allows the team to analyze the materials at the states most relevant to working environments to pinpoint the most active sites. Using a series of biomass upgrading related reactions, the team is measuring and comparing the catalytic activity of the newly synthesized catalysts and identifying the best alternatives to noble metals. The research team attracts diverse undergraduate and graduate students from many disciplines to participate in research. They host and mentor high school students to conduct actual research in their laboratories along with traveling to K-12 schools to demonstrate the power of science. New curricula are developed to introduce students to state-of-the-art methods of materials synthesis and characterization along with extensive catalysis. The team is involved in organization of various conferences aimed at disseminating the materials, material characterization methods, and catalysis processes.