Controlled one-step synthesis of Pt decorated octahedral Fe₃O₄ and its excellent catalytic performance for CO oxidation

A facile one-step co-precipitation method has been applied for the synthesis of a Pt decorated octahedral Fe₃O₄ catalyst. The simple addition of a Pt⁴⁺ and Fe²⁺ mixture into a KOH solution leads to the simultaneous formation of an octahedral Fe₃O₄ and in situ reduction of Pt⁴⁺. HAADF-STEM analysis demonstrates the good dispersion of the Pt species on the Fe₃O₄ (111) plane, and the resulting material exhibits excellent catalytic activity for CO oxidation under moisture conditions. The inevitably existing moisture contributes to the formation of reaction intermediate [COOH] and hence promotes the catalytic activity, which has been proved through in situ DRIFTS analysis.