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.

A simple and low-cost solution-processed method is used to fabricate ZnO/Ag nanowire/ZnO composite UV photodetectors with a large area of 4 × 5 mm², low operating voltage of 1 V and high visible transmittance of 75%. Due to the low-dimensionality confinement ability and small persistent photoconductivity effect in polycrystalline ZnO nanoparticle thin films and excellent conductivity of Ag nanowire networks, composite UV photodetectors exhibit a high on/off ratio and short response time under high light illumination, while exhibiting large detectivity and responsivity under low light illumination. Compared with traditional polycrystalline ZnO thin films, the formation of a large number of Ohmic contacts between ZnO nanoparticles and Ag nanowires in a composite structure greatly improves the extraction number and shortens the extraction time of photoelectrons. Additionally, both Schottky contact and Ohmic contact at the electrode interface can obtain a high on/off ratio and short response time. Our composite structure device is regarded as a compromise between high-performance with large-area, low-voltage and low-cost. It has many advantages compared with its counterparts include ZnO nanowires, and other ZnO composites, which is very promising in UV photodetective applications.

The role of reduction extent of GO in a graphene-based photocatalyst has been studied using Ag/AgX (X = Cl, Br)/rGO composites as a model. The pseudo-second-order kinetics reaction nature of the Ag/AgBr system was also observed.

Enhanced performance of perovskite solar cells based on the application of high quality MAPbI _3−x Cl _x films developed via a hydrobromic acid assisted fast crystallization process is reported.