PVP assisted hydrothermal synthesis of CuCoO2 nanoplates with enhanced oxygen evolution reaction performance

摘要： Tuning size and morphology and exploiting new catalytic materials are several important strategies commonly used to develop highly efficient oxygen evolution reaction (OER) electrocatalysts. In this work, we report the synthesis of CuCoO2 (CCO) nanoplates through a facile one-step PVP assisted hydrothermal process. The influence of hydrothermal reaction parameters, including the precursor composition, reaction temperature and duration, on the morphology, size and crystal phase of CCO crystals has been investigated in detail. In addition, X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) have been used to comprehensively characterize CCO’s crystal structure, morphology, composition and chemical states of elements. Furthermore, the electrocatalytic performance of CCO nanoplates towards the OER is studied and compared to that of CCO micrometer-sized crystals. The CCO nanoplates only require a low overpotential of 390 mV to attain an anodic current density 10 mA cm-2 in alkaline solution, and show comparatively fast OER kinetics with a Tafel slope of 70 mV dec-1 and reasonably good long-term catalytic stability, substantially outperforming CCO micro-crystals, which highlights the importance of size and morphology of CCO for use in OER electrocatalysis.