Recent progress in CO oxidation over Pt-group-metal catalysts at low temperatures

CO oxidation is probably the most studied reaction in heterogeneous catalysis. This reaction has become a hot topic with the discovery of nanogold catalysts, which are active at low temperatures (at or below room temperature). Au catalysts are the benchmark for judging the activities of other metals in CO oxidation. Pt-group metals (PGMs) that give comparable performances are of particular interest. In this mini-review, we summarize the advances in various PGM (Pt, Pd, Ir, Rh, Ru) catalysts that have high catalytic activities in low-temperature CO oxidation arising from reducible supports or the presence of OH species. The effects of the size of the metal species and the importance of the interface between the metal and the reducible support are covered and discussed in terms of their promotional role in CO oxidation at low temperatures. This mini-review summarized the advances of various PGM (Pt, Pd, Ir, Rh, Ru) catalysts for CO oxidation at low temperatures in the past decade, especially those exhibiting comparable performance with the standard gold catalyst.