Construction of Co/Mn-ZIF@Ti3C2Tx composite via in-situ substitution on ZIF-67 for quasi-solid-state supercapacitor with high specific capacitance

Metal-organic frameworks (MOFs) with high specific surface areas, porous structures, and the ability to exchange coordinating ligands have demonstrated exceptional electrochemical performance in supercapacitors. Nevertheless, their conductivity requires further enhancement. Ti3C2Tx, with hydroxyl or terminal oxygen groups on its surface and exhibiting metallic conductivity, can provide additional pathways for ion movement, thereby significantly improving ion transport rates. Based on these concepts, we utilized manganese-doped ZIF-67 MOF as a template and incorporated Ti3C2Tx at an optimal ratio to synthesize the Co/Mn-ZIF@Ti3C2Tx composite for supercapacitors. The Co/Mn-ZIF@Ti3C2Tx electrode exhibits a significantly higher specific capacitance of 1003.3 F center dot g(-1) at 0.5 A center dot g(-1) compared to the original Co/Mn-ZIF electrode and retains 69.3 % of its initial capacitance after 1200 charge-discharge cycles. The assembled Co/Mn-ZIF@Ti3C2Tx//activated carbon asymmetric quasi-solid-state supercapacitor achieves an energy density of 20.85 Wh center dot kg(-1) at a power density of 600.48 W center dot kg(-1). These results surpass those of previously reported supercapacitors, underscoring the potential of the Co/Mn-ZIF@Ti3C2Tx composite for high-performance energy storage applications.