(6h) Discovering Novel Catalysts for Production of Renewable Energy and Fuels | AIChE

(6h) Discovering Novel Catalysts for Production of Renewable Energy and Fuels

Authors 

Yang, X. - Presenter, Princeton University

The eventual exhaustion of fossil fuels and the increasing environmental impacts of greenhouse gas emissions have generated tremendous interest in renewable energy resources and clean energy technologies.  The success of alternative technologies to address these issues in many cases relies on advances in new catalyst materials and catalytic processes, for example in fuel cells and electrolyzers, solar fuels by photocatalysis, biomass conversion, and CO2remediation. To meet the challenges in new catalyst development, my research is primarily focused on understanding high performance catalysts and discovery of new catalysts for energy and environment-related catalysis.

My previous research extensively explored Pt-monolayer and novel non-Pt electrocatalysts for proton exchange membrane (PEM) fuel cells and electrolyzers. This work sought insight into reaction mechanisms and discovery of new materials by establishing clear structure-activity relationships for electrocatalysts.  My studies combined synthesis and characterization of single crystal surfaces in ultrahigh vacuum prepared with well-defined surface structure and evaluation of their catalytic performance under electrochemical conditions. Such samples serve as ideal, model surfaces to study fundamental behavior and properties for functional materials. Supplemented with theoretical simulations, this approach creates an excellent platform to develop new insights into relationships between catalytic performance and surface structure/electronic properties of electrocatalysts.

My recent research focuses on developing high performance heterogeneous catalysts for alkene epoxidation and CO2 conversion. Direct propylene epoxidation by O2 is a challenging reaction because of the strong inherent tendency toward complete combustion. Carbon dioxide emission has been associated with adverse global climate changes. Instead of utilizing capture and sequestration of CO2, a promising way to alleviate this problem is to utilize CO2 as an inexpensive feedstock to produce fuels and possibly other chemicals. My research addresses key scientific issues by combining theoretical and experimental studies on both model surfaces and practical powder catalysts. Advancing our understanding of fundamental principles that can be used to increase selectivity and activity will enable the design of better catalysts. This approach is proving to be valuable. Our discovery of the exceptional catalytic properties of highly mixed oxides is a breakthrough that could lead to developing a new process for propylene epoxidation.  In addition, by synthesizing nanocatalysts and decoding the nature of the active sites, I have identified an unprecedented highly active catalyst for converting CO2/CH4 into methanol. This finding could potentially lead to the design of high performance catalysts for CO2conversion and novel fuel production. 

My future work targets grand challenges involving catalytic processes for developing alternative fuels, new energy technologies, and sustainable green chemistry. Through the integration of both mechanistic studies and practical catalyst development, my research aims to achieve both in-depth understanding of the origins of enhanced catalysts performance and the ability to tune this performance for important applications.