Self-floating biomass charcoal supported flower-like plasmon silver/carbon, nitrogen co-doped defective TiO2 as robust visible light photocatalysts

A self-floating biomass charcoal supported flower-like plasmon Ag/C, N co-doped defective TiO2 photocatalyst is fabricated by hydrothermal, calcination and photo-deposition strategies. Biomass charcoal, Ag nanoparticles, oxygen vacancy defects and C, N co-doping all favor to extend the photoresponse to visible light region. The biomass charcoal plays the role of doping and floating supporter, which can make it float on surface of water and effectively improve the collection of sunlight. The resultant plasmon Ag/C, N co-doped defective TiO2 photocatalyst exhibits excellent visible-light-driven photocatalytic performance, in which the photocatalytic degradation ratio of 2,4-dichlorophenol and hydrogen evolution are up to 95% and 1269 μmol h−1 g−1, respectively, several times higher than that of pristine TiO2. It can be ascribed to the synergistic effect of surface plasmon resonance (SPR) effect of Ag nanoparticles, the efficient C, N co-doping and formation of oxygen vacancy defects promotes spatial charge separation and enhances visible light absorption. In addition, the long-term stability of this novel self-floating photocatalyst implies the potential practical applications.