Semiconductive MOF-Based Supercapacitor Diodes

The supercapacitor-diode (CAPode), which integrates ionic and electronic transport within a single system, holds promise for efficient communication between biological systems and electronic devices, thereby showing significant potential in the next generation of human-machine interaction. However, the operating principles of existing CAPodes are governed by either ion sieving or asymmetric redox, which restrict their compatibility with bioactive ions. Herein, we propose a quantum capacitance (C_Q)-based design for CAPodes, where C_Q, determined by the electronic density of states of electrodes, effectively overcomes such restrictions. Using the porous semiconductive MOF as the working electrode, CAPodes operated effectively across ionic liquid, aqueous, and organic electrolytes, along with realizing "OR" and "AND" logic gate functions, demonstrating versatile electrolyte adaptability. This work expands the fundamental working mechanisms of CAPodes and is expected to facilitate the application of ionic diodes in human-machine interaction.