Wide Temperature All-Solid-State Ti₃ C₂ T_x Quantum Dots/L-Ti₃ C₂ T_x Fiber Supercapacitor with High Capacitance and...

Ti₃ C₂ T_x Quantum dots (QDs)/L-Ti₃ C₂ T_x fiber electrode (Q₃ M₇ ) with high capacitance and excellent flexibility is prepared by a wet spinning method. The assembled units Ti₃ C₂ T_x nanosheets (NSs) with large size (denoted as L-Ti₃ C₂ T_x ) is obtained by natural sedimentation screen raw Ti₃ AlC₂ , etching, and mechanical delamination. The pillar agent Ti₃ C₂ T_x QDs is fabricated by an ultrasound method. Q₃ M₇ fiber electrode gave a specific capacitance of 1560 F cm^-3 , with a capacity retention rate of 79% at 20 A cm^-3 , and excellent mechanical strength of 130 Mpa. A wide temperature all-solid-state the delaminated montmorillonite (F-MMT)/Polyvinyl alcohol (PVA) dimethyl sulfoxide (DMSO) flexible hydrogel (DHGE) (F-MMT/PVA DHGE) Q₃ M₇ fiber supercapacitor is assembled by using Q₃ M₇ fiber as electrodes and F-MMT/PVA DHGE as electrolyte and separator. It showed a volume specific capacitance of 413 F cm^-3 at 0.5 A cm^-3 , a capacity retention of 97% after 10 000 cycles, an energy density of 36.7 mWh cm^-3 at a power density of 311 mW cm^-3 , and impressive capacitance and flexibility over a wide temperature range of -40 to 60 °C. This work provides an effective strategy for designing and assembling wide temperature all-solid-state fiber supercapacitors with optimal balance of capacitive performance and flexibility.