Facets Matching of Platinum and Ferric Oxide in Highly Efficient Catalyst Design for Low-Temperature CO Oxidation

Rational design of supported noble metal is of great importance for highly efficient heterogeneous catalysts. On the basis of the distinct adsorption characteristics of noble metal and transition-metal oxides toward O₂ and CO, the overall catalytic performance of CO oxidation reaction could be further modified by controlling the surface property of the materials to achieve optimal adsorption activity. Here, we studied the influence of facets matching between both platinum and ferric oxide support on CO conversion efficiency. It shows that the activities of four catalysts rank following the order of Pt{100}/α-Fe₂O₃{104} > Pt{100}/α-Fe₂O₃{001} > Pt{111}/α-Fe₂O₃{001} > Pt{111}/α-Fe₂O₃{104}. The strong metal-support interaction and adsorption energy varying with matched enclosed surface are demonstrated by density functional theory based on the projected d-band density of states. Compared with the other three cases, the combination of Pt{100} and α-Fe₂O₃{104} successfully weakens CO poisoning and provides proper active sites for O₂ adsorption. It reveals that the facets matching could be a practicable approach to design catalysts with enhanced catalytic performance.