Double S-Scheme Polydopamine/TiO2/Chlorophyll as Stable and Efficient Green Photoelectrocatalyst

Abstract

Inspired by natural photosynthesis, a new green catalyst with better photocatalytic properties was obtained. Nanostructured TiO2, a cheap cost natural Chlorophyll-a as an electron promotor and a mussel-inspired polydopamine (PD) bio adhesive were synergistically combined in the double S-scheme hybrid photocatalysts The role of PD as a bridging molecule between the pigments of Chl and TiO2 was clearly demonstrated by improved charge transfer and recombination rate. Methylorange as a probe molecule was used to test the stability and efficiency of the new photocatalyst. This challenging approach on obtaining new green bioinspired catalysts avoiding critical raw materials is in line with the new vision on catalysts. The results of this study show the effectiveness and stability of the new photocatalyst. Based on the combined effect of PD functionalization and Chl sensitization, the NT/PD-Chl heterostructure photocatalyst had the best photo(electro)catalytic performance for MO degradation which was shown to be 97.74 % after 180 min.