Constructing KCu7S4/titanium carbide MXene hybrid structure via electrostatic assembly for high-performance supercapacitors

摘要

KCu7S4 electrode materials have attracted much attention for supercapacitors due to its unique one-dimensional channel structure. Herein, KCu7S4@MXene hybrids structure has been prepared through electrostatic hetero-assembly of positively charged 1D KCu7S4 and negatively charged 2D titanium carbide (Ti3C2) MXene for supercapacitor applications. The as-prepared KCu7S4@MXene hybrids not only effectively alleviates the self-stacking problem of Ti3C2 MXene nanosheets, but also endows the hybrids with high conductivity, more exposed electrolyte-accessible active sites. The KCu7S4@MXene electrodes showed better electrochemical performance than individual KCu7S4 nanowires. In particular, the KCu7S4@MXene with a MXene: KCu7S4 mass ratio of 15:1 exhibited a large capacitance of 103.3 F/g at the current density of 2 A/g, is about 4 times that of KCu7S4 nanowires. In additional, it displayed a superior cycle life of 97 capacity retention over 6000 cycles at 1 A/g. This findings offer a new pathway for designing high-performance electrode materials for supercapacitors.