Highly Reversible Molecular Photoswitches with Transition Metal Dichalcogenides Electrodes

Abstract The molecule‐electrode coupling plays an essential role in photoresponsive devices with photochromic molecules, and the strong coupling between the molecule and the conventional electrodes leads to/ the quenching effect and limits the reversibility of molecular photoswitches. In this work, we developed a strategy of using transition metal dichalcogenides (TMDCs) electrodes to fabricate the thiol azobenzene (TAB) self‐assembled monolayers (SAMs) junctions with the eutectic gallium‐indium (EGaIn) technique. The current‐voltage characteristics of the EGaIn/GaO_x//TAB/TMDCs photoswitches showed an almost 100% reversible photoswitching behavior, which increased by ∼28% compared to EGaIn/GaO_x//TAB/Au^TS photoswitches. Density functional theory (DFT) calculations showed the coupling strength of the TAB‐TMDCs electrode decreased by 42% compared to that of the TAB‐Au^TS electrode, giving rise to improved reversibility. our work demonstrated the feasibility of 2D TMDCs for fabricating SAMs‐based photoswitches with unprecedentedly high reversibility.