Growing Co-Ni-Se nanosheets on 3D carbon frameworks as advanced dual functional electrodes for supercapacitors and sodium ion batteries

• Published in: Inorganic chemistry frontiers Vol. 9; no. 15; pp. 3933 - 3942
• Main Authors: Gao, Mingyue, Xue, Yanchun, Zhang, Yutang, Zhu, Chengxing, Yu, Haiwei, Guo, Xingmei, Sun, Shasha, Xiong, Shenglin, Kong, Qinghong, Zhang, Junhao
• Format: Journal Article
• Language: English
• Published: London Royal Society of Chemistry 26.07.2022
• Subjects: Carbon; Chemical etching; Electrode materials; Electrodes; Electron transfer; Energy storage; Inorganic chemistry; Ion exchange; Nanosheets; Reaction kinetics; Selenium; Sodium-ion batteries; Storage systems; Supercapacitors; Wetting
• ISSN: 2052-1553; 2052-1545; 2052-1553
• DOI: 10.1039/d2qi00695b

The reasonable design of electrode materials is crucial for tuning the electrochemical performances of advanced energy storage systems. Co-Ni-Se nanosheets uniformly growing on a butterfly-wing-derived carbon framework (Co-Ni-Se/BWCF) with strong anchoring are devised and prepared by a microwave treatment-ion exchange-chemical etching-hydrothermal selenization technique. Benefiting from its multi-components and unique structure, Co-Ni-Se/BWCF-160 exhibits excellent supercapacitor and sodium storage performances as self-supporting electrodes. When Co-Ni-Se/BWCF-160 is used as a supercapacitor electrode, its capacity is as high as 3050 F g −1 at 1.0 A g −1 and maintained 1006 F g −1 at 20.0 A g −1 . The asymmetric supercapacitor based on Co-Ni-Se/BWCF-160 and a-BWC achieved a high energy density of 49.7 W h kg −1 at 1052 W kg −1 , and the capacity retention reaches 93.3% at 10 A g −1 after 5000 cycles. Evaluated as a sodium ion battery self-supporting anode, the initial discharge specific capacity is up to 703 mA h g −1 at 0.1 A g −1 , and retains 403 mA h g −1 after 100 cycles. More importantly, it still achieves 211 mA h g −1 at 1.0 A g −1 . The overall outstanding electrochemical performances can be explained in that the Co-Ni-Se nanosheets expose more active sites, and the ordered hole arrays ensure sufficient wetting between the electrolyte and electrode materials. Additionally, this unique structure enables more efficient ion/electron transfer and diffusion between the BWCF and Ni-Co-Se, effectively accelerating the electrochemical reaction kinetics. The reasonable design of electrode materials is crucial for tuning the electrochemical performances of advanced energy storage systems.