(159a) Carbon Monoxide Oxidation on Platinum Clusters Adsorbed on Pristine and Boron-Doped Carbon Supports: a Dft Investigation

In the presence of carbon substituted boron defects in carbon supports (graphite and fullerene), we have observed a substantial increase in the adsorption energy of the platinum clusters and other metal atoms like gold, and ruthenium, using first-principles density functional theory (DFT) calculations. This could be used to stabilize the metal nanoparticles on carbon supports and lower the propensity for sintering, which is one of the causes for catalyst deactivation. Experiments are currently underway to test this possibility. The influence of boron-doped carbon supports on the reaction kinetics of the CO oxidation reaction, which is a prominent reaction for catalytic deactivation on the anode of a PEM fuel cell, is being considered here. The process of the adsorption, oxidation of CO by gas phase and adsorbed oxygen and hydroxyl groups, and the CO2 desorption from platinum clusters adsorbed on pristine and boron doped graphite is traced and the activation barriers for different reactions will be presented. The rate constants obtained for different reactions using transition state theory (TST) can be incorporated into a more approximate molecular-level simulation like kinetic Monte Carlo (KMC), which can be used to describe the atomic structure of a catalyst and its reactivity on a larger scale, closer to macroscopic dimensions.