Phase-controlled synthesis of α-NiS nanoparticles confined in carbon nanorods for high performance supercapacitors

• Main Authors: Sun, Chencheng, Ma, Mingze, Yang, Jun, Zhang, Yufei, Chen, Peng, Huang, Wei, Dong, Xiaochen
• Other Authors: School of Chemical and Biomedical Engineering
• Format: Article
• Language: English
• Published: 2015
• Subjects: DRNTU::Science::Medicine::Biomedical engineering
• Online Access: https://hdl.handle.net/10356/106931; http://hdl.handle.net/10220/25230
• Institution: Nanyang Technological University

A facile and phase-controlled synthesis of α-NiS nanoparticles (NPs) embedded in carbon nanorods (CRs) is reported by in-situ sulfurating the preformed Ni/CRs. The nanopore confinement by the carbon matrix is essential for the formation of α-NiS and preventing its transition to β-phase, which is in strong contrast to large aggregated β-NiS particles grown freely without the confinement of CRs. When used as electrochemical electrode, the hybrid electrochemical charge storage of the ultrasmall α-NiS nanoparticels dispersed in CRs is benefit for the high capacitor (1092, 946, 835, 740 F g−1 at current densities of 1, 2, 5, 10 A g−1, respectively.). While the high electrochemical stability (approximately 100% retention of specific capacitance after 2000 charge/discharge cycles) is attributed to the supercapacitor-battery electrode, which makes synergistic effect of capacitor (CRs) and battery (NiS NPs) components rather than a merely additive composite. This work not only suggests a general approach for phase-controlled synthesis of nickel sulfide but also opens the door to the rational design and fabrication of novel nickel-based/carbon hybrid supercapacitor-battery electrode materials.