Sustainable Chemistry

Faculty currently associated with this research theme.

Several groups at the University of Michigan are working towards the development of sustainable reaction processes for the production of valuable chemical targets. The efforts ongoing in our department span many sub-disciplines, including synthetic, computational, spectroscopic, and electrochemical-themed approaches. A representative subset of active research is given below.

Green Catalysis +

Through the NSF Center for Enabling New Technologies through Catalysis (CENTC), the Sanford group is actively involved in developing organometallic catalysts for important chemical transformations including the direct oxidation of simple alkanes and arenes (e.g., methane and benzene) and the reduction of carbon dioxide. Both reactions are problems of critical global significance. Natural gas (which is >90% methane) is becoming an increasingly important precursor to carbon-containing chemicals and liquid fuels as petroleum supplies diminish. Current methods for methane conversion involve steam reforming to syngas followed by the Fisher Tropsch process (to access higher alkanes) or methanol synthesis; however, many major chemical companies have deemed this two-step sequence too costly and inefficient for long-term implementation. The reduction of carbon dioxide, which could be captured from the atmosphere, with hydrogen, ideally derived from a renewal source, could in principle be used to produce methanol. This overall process would be carbon-neutral, and methanol is a potential gasoline replacement and a starting material for the synthesis of many important platform chemicals, including ethylene and propylene.

Controlling Reaction Pathways +

The bond-selective control of a chemical reaction has been a longstanding goal of modern chemical physics. Early attempts using selective laser excitation were thwarted by fast intramolecular energy redistribution. Now ultrafast laser pulses, optical pulse shaping, and feed-back algorithms have been successfully combined in a number of laboratories to control bond dissociation reactions with precision in simple isolated molecules. The Sension group is using tuned optical excitations to efficiently ‘steer’ complex photochemical processes through desired reaction pathways. Through experimental and theoretical work, the aim is to learn how to generate specific and desirable end products.

Low Temperature Semiconductor Preparation +

The preparation and refinement of many groups IV and III-V semiconductors in optoelectronic technologies at scale can be extremely energy intensive and can have significant environmental impacts. The Maldonado group is designing new electrosynthetic strategies to prepare technologically important semiconductors under extremely non-energy-intensive conditions. Using liquid metals as both electrodes for the reduction of dissolved, oxidized precursors and as solvents for re-crystallization, the Maldonado group has developed an electrochemical liquid-liquid-solid (ec-LLS) crystal growth process for the preparation of crystalline Ge, Si, and GaAs at or near room temperature in one step. Through ec‑LLS, functional crystalline semiconductor device components can be prepared in a single process without energy-intensive high temperature annealing, exotic solvents, or caustic reagents.