Ag@AgCl plasmon-induced sensitized ZnO particle for high-efficiency photocatalytic property under visible light

Metal-semiconductor compounds, such as Ag@AgX (X = Cl, Br, I), enable visible light absorption and separation of photogenerated electron–hole through surface plasmon resonance (SPR) effect. However, the electron–hole generated and separated by light are vulnerable in Ag@AgX phase because of the occurrence of secondary recombined. In order to more effectively utilize the SPR photocatalytic effect, a heterojunction interface electric field was implemented effectively by introducing some cost-effective semiconductor materials with wide band gap to Ag@AgX compound, thereby preventing photogenerated electrons from secondarily compounding with the holes. In this article, by mixing 500 nm diameter ZnO and Ag@AgX compounds with mole ratio 1:1, studies show that 15 min illumination under visible light can complete degradation of rhodamine B (RhB), and indicate a high stability of photocatalytic degradation. Through Mott–Schottky plots and photoinduced I–t curve, the results show that through the ZnO/Ag@AgCl composition, heterojunction interface electric field can be formed effectively, thus increasing the separation efficiency and transfer speed of photogenerated electrons and holes, and improving the photocatalytic performance. Meanwhile, Ag@AgCl can implement the photosensitization of ZnO with high efficiency through SPR effect, which will enlarge the response range of photocatalyst to the visible area.