Synthesis of Cobalt Oxide on FTO by Hydrothermal Method for Photoelectrochemical Water Splitting Application

Cobalt oxide thin films were successfully grown directly on fluorine-doped tin glass substrates through a simple, green, and low-cost hydrothermal method. An investigation into the physicochemical characteristics photoelectrochemical (PEC) properties of developed cobalt film was comprehensively performed. At various annealing temperatures, different morphologies crystal phases observed. Microflowers (Co3O4) microflowers with nanowire petals (Co3O4/CoO) produced at 450 °C 550 °C, respectively. Evaluation PEC performance samples in KOH (pH 13), Na2SO4 6.7), H2SO4 1) revealed that highest photocurrent −2.3 mA cm−2 generated −0.5 V vs. reversible hydrogen electrode (RHE) by Co3O4 (450 °C) 1). This corresponded to an 8-fold enhancement compared achieved neutral basic electrolytes higher than results reported other studies. promising generation due abundant source protons, which favorable for evolution reaction (HER) The present study showed is photoactive under acidic conditions, encouraging HER mixed-phase Co3O4/CoO.