1. Structure engineering of nickel silicate/carbon composite with boosted electrochemical performances for hybrid supercapacitors.
- Author
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Tan, Xianfang, Dong, Xueying, Zhang, Fangfang, Huang, Chi, and Zhang, Yifu
- Subjects
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MASS transfer kinetics , *ENERGY density , *TRANSITION metals , *ENERGY storage , *ENERGY conversion , *SUPERCAPACITORS - Abstract
A layer-by-layer strategy is developed to fabricate transition metal silicates/C architecture to enhance their electrochemical properties. [Display omitted] • Layer-by-layer rGO@NiSiO@NiO/C is rationally designed and fabricated. • The rGO@NiSiO@NiO/C shows fast electron/mass transfer kinetics. • The rGO@NiSiO@NiO/C delivers improved electrochemical performances. • The hybrid supercapacitor device achieves the energy density of 26.7 Wh kg−1 at 343.8 W kg−1. In the wake of the carbon–neutral era, the exploration of innovative materials for energy storage and conversion has garnered increasing attention. While nickel silicates have been a focal point in energy storage research, their application in supercapacitors (SCs) has been relatively underreported due to poor conductivity. A newly designed architecture, designated as rGO@NiSiO@NiO/C (abbreviated for reduced graphene oxide (rGO), nickel silicate (NiSiO), nickel oxide/carbon (NiO/C)), has been developed to enhance the electrochemical performance of NiSiO. The incorporation of inner rGO provides structural support for NiSiO, enhancing conductivity, while the outer NiO/C layer not only boosts conductivity but also safeguards NiSiO from structural degradation and electrolyte dissolution. This architecture eliminates multi-phase mixtures, facilitating rapid electron/mass transfer kinetics and accelerating electrochemical reactions, resulting in exceptional electrochemical properties. The rGO@NiSiO@NiO/C architecture achieves a specific capacitance of 324F·g−1 at 0.5 A·g−1, with a superb cycle performance of ∼ 91 % after 10,000 cycles, surpassing state-of-the-art nickel silicates. Furthermore, the hybrid supercapacitor (HSC) device incorporating the rGO@NiSiO@NiO/C electrode attains an areal capacitance of 159 mF·cm−2 at 2.5 mA·cm−2, a retention ratio of ∼ 98 % after 10,000 cycles, and an energy density of 0.68 Wh·m−2 (26.7 Wh·kg−1) at 3.4 W·m−2 (343.8 W·kg−1). This study presents a layer-by-layer approach for constructing transition metal silicates/C architectures to enhance their electrochemical performance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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