One-pot synthesis of Ag/r-GO/TiO₂ nanocomposites with high solar absorption and enhanced anti-recombination in photocatalytic applications

In this paper, we reported a simple one-pot solvothermal approach to fabricate Ag/reduced graphene oxide (r-GO)/TiO₂ composite photocatalyst under atmospheric pressure. Based on the experimental data, we concluded that the introduction of Ag into classical graphene-TiO₂ system (i) efficiently enlarges the absorption range, (ii) improves photogenerated electron separation and (iii) increases photocatalysis reaction sites. The optimized sample exhibits prominent photocatalysis ability as compared to pure TiO₂ under simulated sunlight. We further proposed that besides the above three advantages of Ag, a different size of Ag nanoparticles is also responsible for the improved photocatalysis ability, where small size Ag nanoparticles (2-5 nm) could store a photoexcited electron that was generated from TiO₂, while large-size Ag nanoparticles could utilize visible light due to their localized surface plasmon resonance (LSPR) absorption. Our present work gives new insights into the photocatalysis mechanism of noble metal/r-GO/TiO₂ composites and provides a new pathway into the design of TiO₂-based photocatalysts and promote their practical application in various environmental and energy issues. This journal is