Surface-adsorbed ions on TiO2 nanosheets for selective photocatalytic CO2 reduction

A method based on the adsorption of ions on the surface of two-dimensional (2D) nanosheets has been developed for photocatalytic CO2 reduction. Isolated Bi ions, confined on the surface of TiO2 nanosheets using a simple ionic adsorption method facilitate the formation of a built-in electric field that effectively promotes charge carrier separation. This leads to an improved performance of the photocatalytic CO2 reduction process with the preferred conversion to CH4. The proposed surface ion-adsorption method is expected to provide an effective approach for the design of highly efficient photocatalytic systems. These findings could be very valuable in photocatalytic CO2 reduction applications.