Preferential Carbon Monoxide Oxidation over Copper‐Based Catalysts under In Situ Ball Milling

Abstract

Abstract In situ ball milling of solid catalysts is a promising yet almost unexplored concept for boosting catalytic performance. The continuous preferential oxidation of CO (CO‐PROX) under in situ ball milling of Cu‐based catalysts such as Cu/Cr 2 O 3 is presented. At temperatures as low as −40 °C, considerable activity and more than 95 % selectivity were achieved. A negative apparent activation energy was observed, which is attributed to the mechanically induced generation and subsequent thermal healing of short‐lived surface defects. In situ ball milling at sub‐zero temperatures resulted in an increase of the CO oxidation rate by roughly 4 orders of magnitude. This drastic and highly selective enhancement of CO oxidation showcases the potential of in situ ball milling in heterogeneous catalysis.