With this award, the Chemical Catalysis Program of the NSF Division of Chemistry is funding Dr. Chong Liu of the University of California, Los Angeles to explore new chemistry and reactivity in solution catalysis where the concentrations of reactants and catalysts are controlled in space. Chemical transformations ranging from fundamental investigations to industrial manufacturing are often conducted in solution. It is usually true that the various chemical species are uniformly dispersed throughout the solution. While this often simplifies chemical processes it can also be a limitation. For example, some reactants may not be compatible with each other, with their reactions leading to undesirable side reactions and waste. In these cases it is advantageous to keep these species separated. Dr. Liu is accomplishing this challenge with electrochemistry using arrays of nanometer scale wires. Successful implementation of the proposed work would potentially offer a new paradigm in chemical synthesis with a multifaceted approach involving nanoscience, electrochemistry, and catalysis. Dr. Liu's research team, including women and students from underrepresented groups, will be engaged in highly interdisciplinary research in this project.
Dr. Liu and his team hypothesize that the electrochemistry of nanowire arrays yields controllable local O2 gradient microscopically, which enables O2-sensitive organometallic catalysts to perform oxidative reactions such as direct methane (CH4) to methanol (CH3OH) conversion. Dr. Liuâ€™s research group will design and characterize concentration gradients generated by wire array electrodes, establish a selective CH4-to-CH3OH conversion of O2-deactivating catalysts with O2 oxidant at ambient condition, and explore additional scenarios of solution catalysis that benefits from concentration gradients. This project establishes the design principle of homogenous catalysis with concentration heterogeneity, by addressing two important questions: (1) How can one use electric potential to control and generate a pre-designed concentration profile at microscopic scale? (2) What improvements can be attained for solution catalysis via the establishment of microscopic concentration gradients? The integration of nanoscience and homogenous catalysis provides a unique and potentially powerful approach to control reactions at both molecular and microscopic length scales
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.