High Catalytic Performance of Au/Bi2O3 for Preferential Oxidation of CO in H2

Preferential oxidation (PROX) of CO in hydrogen is of great significance for proton exchange membrane fuel cells (PEMFCs) that need a CO-free hydrogen stream as fuel. The key technical problem is developing catalysts that can efficiently remove CO from the H-2-rich stream within the working temperature range of PEMFCs. Herein, we design a Au/Bi2O3 interfacial catalyst for PROX with excellent catalytic performance, which can achieve 100% CO conversion in the PROX reaction over a wide temperature window (70-200 degrees C) and is perfectly compatible with the operating temperature window (80-180 degrees C) of PEMFCs. Moreover, the catalyst also demonstrates excellent high flow performance and long-term stability. Density functional theory (DFT) calculations reveal that the electrons transferring from Bi2O3 to Au and then to adsorbed perimeter CO and O-2 molecules promote the activation of CO and O-2, thus enhancing the catalytic performance of PROX.

Automated summary

A Au/Bi2O3 interfacial catalyst was designed in this study for preferential oxidation of CO in hydrogen, achieving 100% CO conversion over a wide temperature range and being compatible with the operating temperatures of PEMFCs. The catalyst demonstrated excellent high flow performance and long-term stability. Density functional theory calculations revealed the mechanism behind the enhanced catalytic performance of the catalyst.