Rhodium Nanoparticles/F-Doped Graphene Composites as Multifunctional Electrocatalyst Superior to Pt/C for Hydrogen Evolution and Formic Acid Oxidation Reaction.

Highly efficient electrocatalysis for clean, efficient, and sustainable energy supply, such as hydrogen evolution reaction (HER) and formic acid oxidation reaction (FAOR), has drawn enthusiastic and worldwide attention. Universal and efficient electrocatalysts for these reactions are essential elements for the development of renewable and clean energy technologies. Herein, we show the design and fabrication of the rhodium nanoparticles modified fluorine-doped graphene (Rh/F-graphene) catalyst using silicon nanowires (SiNWs) as the sacrifice template. The optimized Rh/F-graphene catalyst (Rh/F-graphene-2) has a low Rh mass fraction of 9.4% and F doping of 4.0%. The mean diameter of Rh is 9.39 nm. Rh/F-graphene-2 serves as a proton-adsorption-dominated multifunctional electrocatalyst for both HER and FAOR with performance superior to 20 wt % Pt/C in acidic solution. In addition, due to the doping of fluorine, the stability of Rh/F-graphene-2 catalyst greatly improves and is the best among all the compared electrocatalysts. This design for multifunctional catalysts could greatly increase the utilization ratio of Rh, which may provide a new avenue for the preparation of other noble metal-based catalysts.