3D printing quasi-solid-state micro-supercapacitors with ultrahigh areal energy density based on high concentration MXene sediment

3D printing high-efficiency energy storage electrode provides new possibilities for the application of portable and micro devices. This paper reports the preparation of quasi-solid-state symmetrical micro-supercapacitors (MSCs) by direct 3D printing with aqueous MXene Sedimented ink without additives. Once the d-Ti3C2Tx suspension was collected, the MXene sediment (mostly multi-layered MXene and un-etched MAX) was usually discarded. Herein, by adjusting the concentration of MXene sediments in ink to achieve appropriate viscoelasticity, the MSCs with various structures can be printed on the substrate at room temperature via direct ink writing technology. Research discovered that the 3D-printed MSCs had good charge storage capability, with a maximum areal capacitance of 2.337 F cm−2 at 2 mV s−1, areal energy density of 207.81µWh cm−2, power density of 3.74 mW cm−2, and capacitance retention of more than 93.1 % after 10,000 cycles. The MSCs prepared using waste-free MXene ink combined with 3D printing technology provide a useful choice for the fabrication of the next generation of portable and wearable electronic devices.