Molybdenum and sulfur co-doped CoNiO2 with tremella-like nano-structures as electrode material for high-performance supercapacitors

• Published in: Journal of energy storage 2022-12, Vol.56, p.105921, Article 105921
• Main Authors: Wei, Geng, Zhang, Li, Qian, Jin, Yin, Bo, Zhang, Xiaoming, Wang, Zhaomeng, Huang, Haifu, Tang, Shaolong
• Format: Article
• Language: English
• Subjects: CoNiO2; Electrode materials; Energy storage; Heteroatomic doping; Supercapacitors
• ISSN: 2352-152X; 2352-1538
• DOI: 10.1016/j.est.2022.105921

Heteroatomic doping has a significant effect on improving the electrochemical energy storage of metal oxide electrode materials and has been applied in the field of supercapacitors. However, there are few reports on the co-doping of anions and cations into transition metal oxides as the electrode materials in supercapacitors. Herein, the Mo, S co-doped CoNiO2 electrode material with tremella-like nano-structures was successfully prepared on nickel foam (denoted as NiCoMoO-S@NF) via two-step hydrothermal procedures and UV-light irradiation. The co-doping of Mo and S gives the CoNiO2 material a higher specific surface area of 113.98 m2 g−1, abundant active site, and improved electrical conductivity. The obtained NiCoMoO-S@NF shows a high specific capacity of 999.1C g−1 at a current density of 1 A g−1. Moreover, the hybrid supercapacitor device assembled by NiCoMoO-S@NF and rGO@NF can obtain a great energy density of 38.8 Wh kg−1 at a power density of 2880 W kg−1 and shows good cycling stability of 71.6 % capacity retention after 6500 cycles, indicating the excellent supercapacitive properties of NiCoMoO-S@NF and its potential application in supercapacitors. We prepared the Mo, S co-doped CoNiO2 electrode material with tremella-like nano-structures on nickel foam (denoted as NiCoMoO-S@NF) via two-step hydrothermal procedures and UV-light irradiation. The obtained NiCoMoO-S@NF shows a high specific capacity of 999.1C g−1 at a current density of 1 A g−1. Even at a high current density of 20 A g−1, it still maintains a great specific capacitance of 739.5C g−1 and an excellent rate capability of 74.0 %. [Display omitted] •The co-doping of Mo/S into CoNiO2 was achieved via a simple UV irradiation.•The tremella-like nano-structures has a high surface area of 113.98 m2 g−1.•The Mo/S co-doping gives CoNiO2 more active site and improved conductivity.•NiCoMoO-S@NF obtains a high specific capacity of 999.1C g−1 at 1 A g−1.•The hybrid supercapacitor achieves an energy density of 38.8 Wh kg−1.