Niooh-mediated synthesis of gold nanoaggregates for electrocatalytic performance for selective oxidation of glycerol to glycolate / NiOOH诱导金纳米聚集体的合成及其 电催化甘油选择性氧化制乙醇酸盐的性能

In this study, a nickel foam (NF) was treated by cyclic voltammetry (CV) to obtain nickel oxyhydroxide (NiOOH), which was used as the precursor to construct a gold nanoaggregate/foam nickel composite catalyst (Au/RF100-NF, RF represents the surface roughness of NF after CV treatment). The formation of the NiOOH precursors and Au nanoaggregates synergistically enhances the electrochemical active surface area (ECSA) of the Au/RF100-NF while significantly improving the interfacial charge transfer kinetics, thereby contributing to the boosted glycerol oxidation reaction (GOR) performance. Moreover, the formation of Au nanoaggregates promotes the C—C cleavages during GOR, significantly reducing the Faraday efficiency (FE) for lactate (C3product) and markedly increasing the FE for C2and C1products, such as glycolate and formate, over the Au/RF100-NF catalyst. Finally, pulse electrolysis conditions were applied to inhibit the further conversion of glycolate toward formate. As a result, the Au/RF100-NF catalyst achieved highly selectivity to glycolate with a FE up to ca. 49.1%, which was 1.67 times higher than that of the Au/NF catalyst, where Au nanoparticles were directly deposited onto the NF without the formation of NiOOH .