Resumen
In this study, the nanocomposite of g-C3N4 quantum dots/MnCO3 on carbon cloth (q-MC//CC) is prepared via a simple hydrothermal method. The obtained q-MC//CC composite is employed for a flexible supercapacitor electrode. The g-C3N4 quantum dots could effectively improve the interface electrical conductivity and ion transportation of the MnCO3 electrode, which results in superior electrochemical performance. The q-MC//CC electrode delivers a high specific capacity of 1001 F·g-1 at a current density of 1 A·g-1 and a good cycling performance of 96% capacity retention after 5000 cycles. Moreover, an asymmetric flexible supercapacitor (ASC) is assembled with q-MC//CC and carbon cloth as a positive and negative electrode, respectively, which exhibits a high energy density of 27.1 Wh·kg-1 at a power density of 500 W·kg-1. In addition, the fabricated ASC device demonstrates the ability to power the light-emitting diode effectively under mechanical bending.