Synthesis of ultra-fine PtAu solid-solution nanoparticles using silane as the reductant and capping agent for oxygen reduction reaction

Herein, Pt-Au alloy solid solution nanoparticles were successfully prepared in N,N-dimethylacetamide (DMA) solvent system using tert-butyldimethylsilyl hydride (t-BuMe₂SiH) as the reducing agent and stabilizer at room temperature. The metal alloy solid solution nanoparticles of different Pt and Au ratios were 3–5 nm in size and uniformly distributed on carbon black. Compared with aqueous solution, DMA solvent molecules can reduce the electrode potential between different metal reactants and prevent nanoparticle agglomeration, which is conducive to the preparation of monodisperse alloy solid solution nanoparticles and has undeniable advantages. The results of electrocatalytic experiments show that the alloy solid solution catalyst with Pt/Au ratio of 2:1 (Pt₆₇Au₃₃/C) exhibits the highest mass activity and specific activity in oxygen reduction reaction, which are 10 times and 2.9 times of the commercial Pt/C (JM) catalyst, and has good stability. The synthesis strategy of the catalyst has a certain universality, and can also be used to synthesize other alloy solid solution catalysts, which provides a new idea for the preparation of new catalysts with high activity of oxygen reduction reaction.