3D Hierarchical Urchin-Like Ni0.3Co0.6Cu0.1(CO3)0.5(OH) Microspheres for Supercapacitors with High Specific Capacitance

Unitary or binary-metal oxides/hydroxides have been extensively studied as a promising energy storage material. However, their poor rate and cycling performances greatly restrict their practical applications. To address these issues, the electrochemical properties of the materials were improved by unique microstructure designing and multiple active metal-ion doping into the host materials. In this work, the electrode material composed of carbonate hydroxide (Ni0.3Co0.6Cu0.1(CO3)0.5(OH)) formed by co-substituting Co with Ni and Cu was successfully synthesized via a one-step hydrothermal method. The synthetic urchin-like Ni0.3Co0.6Cu0.1(CO3)0.5(OH) active material exhibits excellent electrochemical performance, including a high specific capacitance of 1480 F g–1 at 1 A g–1 and remarkable rate performance with 72.6% capacitance retention with the current density increasing from 1 to 20 A g–1. Additionally, such an electrode material achieves excellent cycling performance with 83.4% capacity retention after 10 000 charge/discharge cycles at a high current density of 10 A g–1, showing great application prospects in energy storage devices.