Carbon quantum dots sensitized Bi2O3 photoanode with enhanced photoelectrocatalytic properties

Bi2O3 is a promising photoelectrocatalyst because of its narrow band gap, stable chemical properties and low price. However, weak photo-response in the visible range and rapid recombination of photogenerated carriers limit its application. Herein, we applied carbon quantum dots (CQDs) as sensitizers, successfully synthesized Bi2O3/CQDs photoelectrode through in-situ layer-by-layer self-assembly to enhance the photoelectrochemical performance. When coupled with CQDs, the transfer of electron-hole pairs is enhanced, and the optical absorption property of the film is improved due to the up-conversion luminescence property of CQDs. As a result, the photocurrent density of Bi2O3/CQDs is ten times higher than that of Bi2O3.