Design of Catalysts and Electrocatalysts for Energy Applications
Speaker: Jingguang Chen, Columbia University
Department: Chemical & Biological Engineering
Location: Engineering Quadrangle A224
Date/Time: Wednesday, April 16, 2014, 4:00 p.m. - 5:00 p.m.
In the current talk we will use two examples to demonstrate the importance of using surface science studies to identify and design catalysts and electrocatalysts. Our research approaches involve parallel efforts in DFT calculations, surface science experiments on model systems, and synthesis and evaluation of supported catalysts under thermochemical or electrochemical conditions. We will first use water electrolysis to demonstrate the feasibility of using monolayer Pt on tungsten carbide (WC) to achieve the same activity as bulk Pt. We will present DFT calculations of similar electronic and chemical properties between monolayer Pt/WC and Pt, synthesis and characterization of monolayer Pt/WC films, and electrochemical evaluation of the activity and stability of Pt/WC for water electrolysis. Comparing to the leading Pt electrocatalyst, the monolayer Pt/WC represents a significant reduction in Pt loading in electrolyzers and photoelectrochemical devices.
We will then use the conversion of biomass-derived oxygenates to illustrate the advantages of using bimetallic catalysts. Bimetallic catalysts often show unique activity and selectivity over their parent metals due to the electronic modification and strain effect. We will present our results on the characterization of Ni/Pt bimetallic model surfaces and supported catalysts under in-situ reaction conditions, further highlighting the importance of using the combined approaches of DFT calculations, surface science experiments, and reactor evaluations for catalyst discovery.