Flexible gold nanoparticles/rGO and thin film/rGO papers: novel electrocatalysts for hydrogen evolution reaction

Abstract BACKGROUND Fabrication of cost‐effective and durable materials for efficient hydrogen production in splitting water (hydrogen evolution reaction) is of importance for the successful utilization of hydrogen‐based green energy technologies. Therefore, electrocatalytic materials have been designed with a simple approach using electrodeposition of gold nanoparticles (AuNPs) and thin film (AuTF) directly on reduced graphene oxide (rGO) paper. As‐prepared paper electrocatalysts (AuNPs/rGO and AuTF/rGO) were characterized by X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM). RESULTS Free‐standing and flexible AuNPs/rGO and AuTF/rGO electrocatalysts have exhibited excellent performances on HER with low Tafel slopes (88 and 112 mV dec −1 ), low onset potentials (−47 and −55 mV), small overpotentials of only −176 and −204 mV to drive 10 mA cm −2 , respectively, and high durability even with the rolled design. The outstanding performance of these two electrocatalysts can be attributed to the uniform distribution of 20‐nm‐sized AuNPs and the deposition of well‐ordered AuTF on rGO paper, providing an increment in the surface area and an enhancement of the electron density. CONCLUSION The controllable design of AuNPs/rGO and AuTF/rGO electrocatalysts, together with their high flexibility, good stability and promising results, suggest potential use in future applications of H 2 production in splitting water. © 2019 Society of Chemical Industry