Unlocking Novel Functionality: Pseudocapacitive Sensing in MXene-Based Flexible Supercapacitors

• Discovery of a novel phenomenon where pseudocapacitance of flexible MXene supercapacitors changes sensitively in response to bending, leading to the development of Pseudocapacitive Sensors. • Pseudocapacitive Sensors repurpose supercapacitors as strain sensors, detecting capacitance changes from shifts between pseudocapacitance and electrical double layer capacitor, achieving a gauge factor of about 1200. • The sensing mechanism relies on local pH changes induced by bending, which switch energy storage kinetics from Faradaic protonation to non-Faradaic adsorption. • This work expands the application of pseudocapacitance from energy storage to multifunctional electronics, with potential in robotics, biomedical devices, and health monitoring.