Nanosphere-like NiSe2/SnSe2 composite electrode materials with excellent performance for asymmetric supercapacitor. (October 2021)

• Record Type: Journal Article
• Authors: Wu, Shang; Zhou, Sheng; Feng, Qiaoliang; Zhao, Huanlei; Xu, Xin; Cui, Tao; Zhang, Hong; Wang, Xia; Yang, Quanlu
• Is Part Of: Journal of energy storage. Volume 42(2021)
• Publication Date: 2021-10
• Subjects: Tin metal -- Nickel metal -- Bimetallic selenides -- Asymmetric hybrid supercapacitors -- Nanosphere; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2021.103032
• Languages: English
• ISSNs: 2352-152X

Abstract

Highlights: Nanosphere-like NiSe2 /SnSe2 composite is prepared by a simple two-step method. The NiSe2 /SnSe2 microspheres shows a particle aggregation structure and has an excellent specific capacity. Pioneering synthesis of a new structure of Ni/Sn bimetallic compound. The ASCs device exhibits high specific energy. Abstract: Tin metal was widely used in energy storage and photovoltaic devices due to its high stability and high conductivity. However, due to its low electrochemical performance, the application of tin compounds in supercapacitors was rarely reported. In this paper, it was first used a simple two-step hydrothermal method to design a nanospherical NiSe2 /SnSe2 composite as supercapacitor electrode materials. The composite exhibited excellent electrochemical properties, it not only increased conductivity and provided more active sites, but also shortened electron and ion transport paths. The (Ni, Sn)Se2 -2.5 exhibited an appealing specific capacity (116 mA h g −1 at 1 A g −1 ) and better cycle stability (80% capacity retention after 4000 cycles). Moreover, asymmetric supercapacitors which were assembled with (Ni, Sn)Se2 -2.5 and activated carbon had superior electrochemical performance. When the specific power was 855 W kg −1, the specific energy can reached 34.2 Wh Kg −1 and accompanied by an efficient stability (82.3% of capacity retention after 10000 cycles). Therefore, the synthesized spherical (Ni, Sn)Se2 -2.5 possessed excellent prospects as electrode materials for supercapacitors. Graphic abstract: Image, graphical abstract The Nanosphere-like NiSe2 /SnSe2 composite were synthesized by the two-step solvothermal method and matched with activated carbon materials. The designed asymmetric supercapacitor possesses high specific energy and power and a long-term cycling lifespan. Therefore, the performance of asymmetric supercapacitors proves that controlling the morphology can play a key role in energy storage devices.