Two‐dimensional bifunctional electrocatalyst (Mo–NiFe‐LDH) with multilevel structure for highly efficient overall water splitting

Abstract

Abstract To effectively address energy challenges, it is crucial to explore efficient and stable bifunctional non‐precious metal catalysts. In this study, a Mo‐doped nickel–iron layered double hydroxide with flower‐cluster architecture was successfully prepared by a one‐step hydrothermal method, which demonstrated a good water splitting performance. After an appropriate amount of Mo doping, some lattice distortions in the material provided reactive sites for the adsorption and conversion of intermediates, thus optimising the charge distribution of the material. Moreover, the multidimensional void structures formed after doping had a larger specific surface area and accelerated the penetration of the electrolyte, which significantly improved the activity of the catalyst in alkaline media. At 10 mA·cm −2 , the hydrogen and oxygen evolution overpotentials of Mo‐doped nickel–iron double hydroxides (Mo–NiFe LDH/NF‐0.2) were 167 and 220 mV, respectively, with an excellent durability up to 24 h. When the Mo–NiFe LDH/NF‐0.2 catalyst was used as the cathode and anode of an electrolytic cell, the catalyst achieved a current density of 10 mA·cm −2 at an applied voltage of 1.643 V. This study provides a novel approach for designing excellent bifunctional electrocatalysts containing nonprecious metals.