Electrochemically-Switched 2nd Order Non-Linear Optical Response in an Arylimido-Polyoxometalate with High Contrast and Cyclability

Angew Chem Int Ed Engl. 2023 Jan 26;62(5):e202215537. doi: 10.1002/anie.202215537. Epub 2022 Dec 27.

Abstract

Electrochemically switched 2nd order non-linear optical responses have been demonstrated for the first time in polyoxometalates (POMs), with an arylimido-derivative showing a leading combination of high on/off contrast (94 %), high visible transparency, and cyclability. Spectro-electrochemical and TD-DFT studies indicate that the switch-off results from weakened charge transfer (CT) character of the electronic transitions in the reduced state. This represents the first study of an imido-POM reduced state, and demonstrates the potential of POM hybrids as electrochemically activated molecular switches.

Keywords: Donor-Acceptor Systems; Molecular Devices; Nonlinear Optics; Polyoxometalates; Spectroelectrochemistry.