Porous nickel–cobalt phosphate with oxygen-rich vacancies in situ grown on dopamine-modified cellulose textiles as self-supporting high mass loadings supercapacitor electrode

• Published in: Journal of colloid and interface science Vol. 677; no. Pt B; pp. 626 - 636
• Main Authors: Tian, Wenhui, Ren, Penggang, Hou, Xin, Fan, Baoli, Wang, Yilan, Pei, Lu, Wang, Hongtao, Chen, Zhengyan, Jin, Yanlin
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.01.2025
• Subjects: High mass loading; Nickel cobalt phosphate; Oxygen vacancies; Supercapacitor; Supercapacitor; Oxygen vacancies; High mass loading; Nickel cobalt phosphate
• ISSN: 0021-9797; 1095-7103; 1095-7103
• DOI: 10.1016/j.jcis.2024.08.112

[Display omitted] Transition-metal phosphates/phosphides showcase significant promise for energy-related applications because of their high theoretical electrochemical characteristics. However, sluggish electro/ion transfer rates and kinetically unfavorable reaction sites hinder their application at high mass loading. Herein, a self-supporting electrode based on transition-metal phosphates was successfully fabricated via a one-step electrodeposition process. The nanosheet structure of transition-metal phosphates, formed by interconnecting nanoparticles, effectively mitigates the impact of stress and achieves a high mass-loading (21 mg cm−2) of the electrode. Additionally, the oxygen vacancy-rich and porous nanostructure of transition-metal phosphates endows the as-prepared electrodes with a significantly increased conductivity and fast ion migration rate for enhancing electrochemical kinetics. Consequently, the as-fabricated transition-metal phosphate electrode displays the highest areal specific capacity of 39.2F cm−2. Furthermore, the asymmetric supercapacitor achieves a maximum energy density of 0.79 mWh cm−2 and a high capacity retention of 93.0 % for 10000 cycles under 60 mA cm−2. This work provides an ideal strategy for fabricating flexible electrodes with high mass loading and synthesizing transition-metal phosphate electrodes rich in oxygen vacancies.