Abstract

Climate change and ocean acidification are expected to be two of the most difficult scientific challenges of the 21st century. Converting CO₂ into valuable chemicals and fuels by using heterogeneous catalysis is one of the most practical routes for reducing CO₂ emissions. Using hydrogen, CO₂ can be converted to three types of products: CO through the reverse water-gas shift (RWGS) reaction, methanol via selective hydrogenation, and methane through methanation reaction. Using ethane, CO₂ can be converted to a useful feedstock (synthesis gas) and a value-added monomer (ethylene) via the dry reforming pathway through the C-C bond scission and the oxidative dehydrogenation pathway through the C-H bond scission, respectively. By using combined in-situ characterization and density functional theory (DFT) calculations, the catalytic activity and selectivity can be rationally optimized. Therefore, this work aims to (1) gain a better understanding of the capability of different active metal-oxide interfaces and active metal oxidation states in tuning activity and selectivity for CO₂ hydrogenation reactions by optimizing binding energies of key intermediates; (2) identify different active sites on FeNi/CeO₂ catalysts to convert CO₂ and light alkanes to synthesis gas via the dry reforming pathway through the C-C bond scission, and to olefins via the oxidative dehydrogenation pathway through the C-H bond scission; (3) explore the origin of the bimetallic effect for dry reforming of ethane and butane over PtNi/CeO₂.

Biography:

Binhang Yan received his B.S. degree (2008) and Ph.D. degree (2013) in Chemical Engineering from Tsinghua University. Currently he is a postdoctoral fellow in the Chemistry Department at Brookhaven National Laboratory. His research is mainly focused on reaction mechanism studies and selectivity tuning strategies for heterogeneous catalysis, including catalytic reduction of CO₂, CO₂ assisted oxidative dehydrogenation, dry reforming of alkane, and selective hydrogenation reactions.