文摘
Cobalt-doped Pt–Au alloy nanoparticles with a narrow size distribution and small sizes of ca. 4 nm were deposited on ultrathin α-Co(OH)2 nanosheets through a one-pot method. The whole process could be divided into two steps: coreduction by NaBH4 and subsequent partial oxidation by air. The compositions of the as-prepared y-PtxAu100–x/Co(OH)2 (x = 0, 25, 50, 75, 100, y = 1 %, 10 %) materials can be accurately controlled by adjusting the amounts of the raw materials. The structure of y-PtxAu100–x/Co(OH)2 was affected by the doped cobalt. The effects of ultrathin α-Co(OH)2 nanosheets and the chemical composition of PtxAu100–x NPs on the catalytic activity for the reduction of 4-nitrophenol (4-NP) were investigated systematically. 1 %-Pt50Au50/Co(OH)2 exhibits the most significantly enhanced catalytic activity. Its much higher activity than those of 1 %-Pt/Co(OH)2, 1 %-Au/Co(OH)2, and a physical mixture of Pt50Au50 nanoparticles and ultrathin α-Co(OH)2 nanosheets suggests that there is a synergy between the Pt and Au and between the PtxAu100–x nanoparticles and the supports.