Ni0.9Co1.92Se4 nanostructures: binder-free electrode of coral-like bimetallic selenide for supercapacitors

• Published in: RSC advances Vol. 6; no. 79; pp. 75251 - 75257
• Main Authors: An, Weidan, Liu, Ling, Gao, Yanfang, Liu, Yang, Liu, Jinrong
• Format: Journal Article
• Language: English
• Published: 01.01.2016
• Subjects: Architecture; Capacitance; Current density; Electrode materials; Electrodes; Energy density; Nanostructure; Supercapacitors
• ISSN: 2046-2069
• DOI: 10.1039/c6ra17825a

Coral-like Ni0.9Co1.92Se4 nanostructured materials have been prepared through a simple and controlled two-step solvothermal method, which present a handsome electrochemical performance. The specific capacitance reaches 1021.1 F g-1 under the current density of 2 mA cm-2 over a 0.5 V electrode potential window with an areal capacitance of 6.43 F cm-2. A superior rate capability of 77% is achieved with discharge rates increasing from 2 to 50 mA cm-2, as well as a good cycling stability of 88.39% after 5000 cycles. Furthermore, a good energy density of 26.29 W h kg-1 is achieved under the power density of 265 W kg-1 when assembled into a Ni0.9Co1.92Se4//AC asymmetric supercapacitor with the operating potential window extended to 1.5 V. The high performance can be attributed to the coral-like architectures with rich redox reactions, high conductivity and transport rate for both electrons and electrolyte ions. Our results suggest that the coral-like Ni0.9Co1.92Se4 nanostructured electrode materials may be a good choice for supercapacitors.