CoNi2 S4 Electrode with High Mass-Loading for High-Energy-Density Supercapacitor: Role of S-Containing Anions Exchange

• Published in: Chemistry : a European journal Vol. 29; no. 26; p. e202203898
• Main Authors: Wang, Lingfeng, Chen, Lu, Chen, Shihuan, Ye, Qinglan, Xu, Xuetang, Wang, Fan
• Format: Journal Article
• Language: English
• Published: 08.05.2023
• ISSN: 1521-3765; 1521-3765
• DOI: 10.1002/chem.202203898

Anion exchange is recognized as an effective method to regulate the composition, electronic conductivity, and electrochemical behavior of the transition metal-based compounds. In this work, anion exchange is adopted as a rational post-treatment route to facilitate the capacitive activity of CoNi2 S4 nanoparticle arrays grown on carbon cloth (CC) with high mass-loading. As soaked in saturated Na2 S solution, the CoNi2 S4 /CC electrode showed an increased capacity from 483 C g-1 to 841 C g-1 at 10 mA cm-2 with excellent rate performance and stable cycling performance, which was superior to the CoNi2 S4 /CC electrode activated by NaBH4 reduction. Anion exchange was beneficial for enhancing the crystallinity, retaining the adhesion of nanoarrays, and realizing low resistance nature in a mild route. The as-assembled CoNi2 S4 /CC//activated CC hybrid supercapacitor delivered a high areal capacitance of 1.28 F cm-2 at 5 mA cm-2 , and achieved an energy density of 0.58 mWh cm-2 at a power density of 4.5 mW cm-2 with excellent cycle stability with 90.6 % capacity retention after 10000 cycles.Anion exchange is recognized as an effective method to regulate the composition, electronic conductivity, and electrochemical behavior of the transition metal-based compounds. In this work, anion exchange is adopted as a rational post-treatment route to facilitate the capacitive activity of CoNi2 S4 nanoparticle arrays grown on carbon cloth (CC) with high mass-loading. As soaked in saturated Na2 S solution, the CoNi2 S4 /CC electrode showed an increased capacity from 483 C g-1 to 841 C g-1 at 10 mA cm-2 with excellent rate performance and stable cycling performance, which was superior to the CoNi2 S4 /CC electrode activated by NaBH4 reduction. Anion exchange was beneficial for enhancing the crystallinity, retaining the adhesion of nanoarrays, and realizing low resistance nature in a mild route. The as-assembled CoNi2 S4 /CC//activated CC hybrid supercapacitor delivered a high areal capacitance of 1.28 F cm-2 at 5 mA cm-2 , and achieved an energy density of 0.58 mWh cm-2 at a power density of 4.5 mW cm-2 with excellent cycle stability with 90.6 % capacity retention after 10000 cycles.