Supercapacitively Liquid‐Solid Dual‐State Optoelectronics

Abstract Photo‐transduction of solid‐state optoelectronics occurs in semiconductors or their interfaces. Considering the confined active area and interfacial capacitance of solid‐state materials, solid‐state optoelectronics faces inherent limitations in photo‐transduction, especially for bionic vision, and the performance is lower than that of living systems. For example, a photoreceptor generates pA‐level photocurrent when absorbing a single photon. Here, a liquid‐solid dual‐state phototransistor is demonstrated, in which photo‐transduction and modulation take place at the microporous interface between semiconductors and water, mimicking principles of the photoreceptor. When operating in the water, an orderly stacked photo‐harvesting covalent organic framework layer generates supercapacitively photogating modulation of the channel conductivity via a dual‐state interface, achieving responsivity of 4.6 × 10 10 A W −1 and detectivity of 1.62 × 10 16 Jones at room temperature, several orders of magnitude higher than other photodetectors. Such bio‐inspired dual‐state optoelectronics enables high‐contrast scotopic neuromorphic imaging with responsivity greater than photoreceptors, holding promise for constructing optoelectronic systems with performance beyond conventional solid‐state optoelectronics.