Self-template synthesis of double shelled ZnS-NiS1.97 hollow spheres for electrochemical energy storage

Publication date: 30 March 2018
Source:Applied Surface Science, Volume 435
Author(s): Chengzhen Wei, Qinglong Ru, Xiaoting Kang, Haiyan Hou, Cheng Cheng, Daojun Zhang
In this work, double shelled ZnS-NiS1.97 hollow spheres have been achieved via a simple self-template route, which involves the synthesis of Zn-Ni solid spheres precursors as the self-template and then transformation into double shelled ZnS-NiS1.97 hollow spheres by sulfidation treatment. The as-prepared double shelled ZnS-NiS1.97 hollow spheres possess a high surface area (105.26 m² g⁻¹) and porous structures. Benefiting from the combined characteristics of novel structures, multi-component, high surface area and porous. When applied as electrode materials for supercapacitors, the double shelled ZnS-NiS1.97hollow spheres deliver a large specific capacitance of 696.8C g⁻¹ at 5.0 A g⁻¹ and a remarkable long lifespan cycling stability (less 5.5% loss after 6000 cycles). Moreover, an asymmetric supercapacitor (ASC) was assembled by utilizing ZnS-NiS1.97 (positive electrode) and activated carbon (negative electrode) as electrode materials. The as-assembled device possesses an energy density of 36 W h kg⁻¹, which can be yet retained 25.6 W h kg⁻¹ even at a power density of 2173.8 W Kg⁻¹, indicating its promising applications in electrochemical energy storage. More importantly, the self-template route is a simple and versatile strategy for the preparation of metal sulfides electrode materials with desired structures, chemical compositions and electrochemical performances.

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