Mechanistic investigation of Mg²⁺-ion-induced ZnO nanorods for enhanced photocatalytic performance

In this study, Mg²⁺ ions-doped ZnO nanorods were prepared via simple solvothermal method. The prepared samples were characterized by XRD, TEM/SEM, EDX, UV–visible and PL emission spectroscopy to explore the structural, morphological and optical properties, respectively. The XRD results reveal that Mg²⁺ ions-doped ZnO/MgO nanocomposite exhibited the hexagonal wurtzite structure of ZnO. However, the incorporation of Mg²⁺ ions into ZnO has shifted the XRD peaks towards lower 2Ө angles which might be due to successful incorporation of Mg²⁺ ions into ZnO lattice. Moreover, the prepared ZnO, MgO and MgO/ZnO nanocomposites with various Mg to Zn atomic ratios (2–11%) were used as photocatalyst for the degradation of MB and RhB dyes under visible light irradiation. The sample with 8% doping (8%MgO/ZnO) showed excellent photocatalytic performance for both dyes as compared to pure ZnO and other samples. Furthermore, the cyclic stability of 8% MgO/ZnO nanocomposite was also monitored for the degradation of RhB dye, the results show that the prepared nanocomposite has good stability and long-term durability after five consecutive cycles. The current study suggests that ZnO/MgO-based nanocomposites could be proficiently used in numerous applications especially in environmental and energy applications.