Efficient visible-light-driven photocatalytic performance for nitrogen oxide abatement application in the air by a typical metal/semiconductor heterojunction

To improve the photocatalytic oxidation activity of SnO2 nanorods, we decorated Ag nanoparticles onto SnO2 nanorods via a photoreduction route at low temperature. The metal/semiconductor heterojunction based on Ag/ SnO2 nanorods indicated a high photocatalytic activity towards NO gas removal in visible light region at the air conditions. Detailly, the NO photocatalytic removal performance of Ag/SnO2 heterojunctions are significantly enhanced, achieving 50.6 % after 30 min, approximately 1.9 times higher than that of SnO2 nanorods. In addition, the Ag/SnO2 heterojunctions have a lower NO2 gas conversion efficiency of 1.0 %, while pure SnO2 nanorods have a high NO2 conversion efficiency of 5.2 %. Moreover, photogenerated holes play a crucial role in the photocatalytic activity of NO gas removal.