Novel Interconnected Nickel–Iron Layered Double Hydroxide Nanoweb Structure for High‐Performance Supercapacitor Electrodes

Abstract Many emerging technologies urgently require powerful energy storage devices, and their development depends largely on advances in material performance to meet commercialization requirements. Here, the synthesis of a novel structure of a Ni–Fe layered double hydroxide (LDH) interconnected nanoweb is achieved at low temperature (100 °C) using a wet‐chemistry synthesis method. The 3D porous structure consists of interconnected nanowires and produces a very high specific capacitance of 1656.0 F g⁻¹ at a scan rate of 1 mV s⁻¹, which is more than double that recorded for a conventional Ni–Fe LDH nanosheet with a wrinkled structure (787.2 F g⁻¹ at 1 mV s⁻¹). This superior performance is primarily attributed to the 3D porous structure, which provides a large surface area and facilitates electron transport along the interconnected nanowires, thereby shortening the electrolyte diffusion path. A hybrid supercapacitor using the Ni–Fe LDH nanoweb as the cathode material has a high capacitance of 56.2 F g⁻¹ with an energy density of 20.0 Wh kg⁻¹. This unique structure offers significant potential for the preparation of high‐performance supercapacitors and opens a new route for the structural design and development of high‐efficiency electrode materials in numerous energy storage fields.