Facile synthesis of nickel-cobalt sulfide/reduced graphene oxide hybrid with enhanced capacitive performanceElectronic supplementary information (ESI) available. See DOI: 10.1039/c5ra09447j

• Main Authors: Cai, Xiaoqing, Shen, Xiaoping, Ma, Lianbo, Ji, Zhenyuan, kong, Lirong
• Format: Article
• Language: English
• ISSN: 2046-2069
• DOI: 10.1039/c5ra09447j

A uniform hybrid with nickel-cobalt sulfide (NiCo 2 S 4 ) nanoparticles attached on reduced graphene oxide (RGO) nanosheets is fabricated through a facile one-pot refluxing method. NiCo 2 S 4 nanoparticles with sizes of several nanometers uniformly disperse on the surface of RGO sheets, and the electrochemical properties of the resulting NiCo 2 S 4 /RGO hybrids are investigated by using them as electrode materials for a supercapacitor. The NiCo 2 S 4 /RGO hybrids deliver a maximum specific capacitance of 1526 F g −1 at the current density of 1.0 A g −1 , and a high rate capability, retaining 1109 F g −1 at a high current density of 20 A g −1 . Moreover, after 2000 charge-discharge cycles at the current density of 10 A g −1 , 83% of the initial capacitance is maintained, indicating a good cycling stability. The enhanced capacitive performance can be attributed to the synergistic effect between NiCo 2 S 4 nanoparticles and RGO, in which RGO can provide conductive channels and serve as an ideal support matrix. The facile synthesis and the remarkable capacitive performance of the NiCo 2 S 4 /RGO hybrid make it a promising candidate for electrode materials in electrochemical energy conversion/storage devices. A facile one-pot refluxing method was developed to prepare nickel-cobalt sulfide/reduced graphene oxide (RGO) hybrids. The as-synthesized NiCo 2 S 4 /RGO hybrids as electrode materials for supercapacitors exhibit excellent electrochemical performance.