Luminescence Amplification at BiVO4 Photoanodes by Photoinduced Electrochemiluminescence

Angew Chem Int Ed Engl. 2020 Aug 24;59(35):15157-15160. doi: 10.1002/anie.202004634. Epub 2020 Jun 9.

Abstract

Photoinduced electrochemiluminescence (PECL) combines semiconductor (SC) photoelectrochemistry with electrochemiluminescence (ECL). In PECL, the incident light is converted into a different wavelength by an electrochemical reaction at a SC photoelectrode and allows triggering of ECL at low potentials. This concept has been employed to design up-conversion systems. However, PECL strongly suffers from the photoelectrochemical instability of these low band gap SCs. Reported here for the first time is an original light-conversion strategy based on PECL of a luminol derivative (L-012) at BiVO4 photoanodes in water. Incident light photoexcites simultaneously the L-012 fluorescence and the photoanode. However, the resulting signal is surpassed by the PECL emission. PECL can be induced at a potential as low as -0.4 V for several hours and can be employed to finely tune L-012 luminescence. This finding is promising for the design of new analytical strategies and light-addressable systems.

Keywords: fluorescence; luminescence; photoelectrochemistry; semiconductors; water.