Mechanistic insights into the support effects of Cu catalysts in hydrogen combustion

Support effects play a pivotal role in most heterogeneous catalysts, and understanding the underlying catalytic mechanism is crucial for guiding catalyst design and optimizing performance. In this study, we conduct a kinetics and mechanistic investigation into the support effects of Cu catalysts in hydrogen combustion by comparing reducible and nonreducible supports. Multiple characterization techniques are employed to comprehend the support effects, with the reducible support and low-valence Cu species highlighted for the most active Cu/ZrO2 catalyst. A redox-based kinetics strategy is further proposed by decoupling the reduction step and oxidation step. The as-obtained reduction and oxidation rate diagram indicates a significantly enhanced reduction rate for the reducible supported catalyst, attributed to the abundant surface oxygen vacancy for the generation of hydroxyl intermediates. These efforts aim to develop more efficient kinetics-based techniques for unraveling the nature of support effects, thereby offering a rational approach to designing highly active catalysts.