Abstract

Rare earth hydroxides have attracted growing interest in energy storage research owing to their favourable redox chemistry, multiple accessible oxidation states, and robust electrochemical stability. In this work, gadolinium hydroxide (Gd(OH)3) was prepared by microwave-assisted approach and evaluated as an electrode material for supercapacitor. Crystallographic and morphological studies confirmed the successful formation of crystalline hydroxide with a nanorod-like hierarchical morphology. The electrochemical behaviour of the prepared material was investigated, revealing a high specific capacitance of 894 F g−1 at 1 A g−1. Furthermore, the practical applicability of the synthesized Gd(OH)3 was demonstrated by assembling an asymmetric solid-state supercapacitor device, which delivered an energy density of 16 Wh kg−1and a power density of 2000 W kg−1, along with excellent cycling stability. These results highlight the strong potential of Gd(OH)3 as a promising electrode material for supercapacitor applications.