Supported Binary and Ternary Nanoalloy Nanoparticle Catalysts-A Green Processing Approach using the Leidenfrost layer as Nanoreactor

Abstract When a nanocarbon substrate is heated between 300 °C and 320 °C that is slightly above the Leidenfrost temperature and subsequently quenched in an aqueous solution containing a mixture of noble metal ions, a high density of nanoalloy nanoparticles (NPs) form on the surface. Large surface areas can be decorated in this way by nanoalloy NPs of the system (Au, Pt, Pd). Both binary AuPt, AuPd and PtPd as well as ternary nanoalloys are obtained. The chemical composition of the nanoalloys can be tuned by varying the ion mixture ratio of the solutions. The simultaneous reduction of the noble metal ions on the surface occurs without the need of any reducing agent, presumably owing to charge transfer from ionized species during the quenching process. The method yields nanocarbon-supported, highly adherent nanoalloy NPs, is materials efficient and cost effective because only the surface is modified with the costly noble metals. The supported nanoalloy NPs are exemplary applied to the electrooxidation of methanol and formic acid in acidic solutions, and show an overall high performance.