Direct growth of highly organized, 2D ultra-thin nano-accordion Ni-MOF@NiS2@C core-shell for high performance energy storage device

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2021-02, Vol.406, p.126810, Article 126810
• Main Authors: Lee, Chang Soo, Lim, Jeong Min, Park, Jung Tae, Kim, Jong Hak
• Format: Article
• Language: English
• Subjects: Core-shell; Flexible; Metal-organic framework (MOF); nickel sulfide; Supercapacitor; Surfactant
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2020.126810

[Display omitted] •The P-NMSC was carried out by a solvothermal and sulfurization.•The boundary region of P-Ni-MOF converted into NiS2@C.•The resulting P-NMSC exhibited the ultrahigh areal specific capacitance value.•Its good performance is attributed to the highest specific surface area.•The solid-state flexible ASC device exhibited an excellent areal specific capacitance. Metal-organic framework (MOF) as an active material is a state-of-the-art challenge to improve performance of energy storage devices due to its high porosity, ion diffusion channel and provision of redox sites. Nevertheless, the development of next-generation devices requires overcoming shortcomings such as low electrical conductivity and low MOF stability. Herein, the in situ growth of a nickel-based MOF on a Ni foam and the formation of a Ni-MOF@NiS2@C (NMSC) core-shell hetero-nanostructure is reported to overcome the challenge of using MOFs as active materials. Additionally, a surfactant-assisted approach is demonstrated to construct an ultra-thin 2D nano-accordion structure with interstitial gaps between the nanosheets. The unique nano-accordion structure facilitates faster ion diffusion and decreases the total resistance owing to the excellent charge transfer ability. In particular, the solid-state flexible supercapacitor exhibited a high performance with a specific capacitance of 283.5 F g−1 with an excellent energy density of 77.2 W h kg−1 at a power density of 7000 W kg−1.