Preparation of muscovite/tungsten-doped TiO2 composites for the efficient photocatalytic degradation of methyl orange under simulated solar light irradiation

Abstract

TiO 2 particles were supported on the surface of muscovite by van der waals force and Ti O Si bond, which improved the adsorbability and recyclability of TiO 2 . Meanwhile, W-doped could introduce new energy levels below the TiO 2 conduction band to reduce the band gap, enhance the absorption of sunlight, and promote the separation of electron-hole pairs, so as to improve the photocatalytic activity of the M/W-TiO 2 composite. • The M/W-TiO 2 composite photocatalyst was fabricated by one-step hydrothermal method. • Endow muscovite with the ability of photocatalysis. • The existence of W-doped energy level improves the separation efficiency of photogenerated carriers. • M/W-TiO 2 composites exhibit excellent photocatalytic activity and stability under simulated solar light irradiation. Metal oxide semiconductors have a widespread application in the photocatalytic treatment of dye wastewater but there is a need to improve the current ‘champion’ titanium dioxide (TiO 2 ) due to its difficult recovery, low utilization rate of sunlight, and fast recombination of electron-hole pairs. To solve the problems, muscovite-supported TiO 2 with tungsten dopant (M/W-TiO 2 ) photocatalyst was synthesized using a facile hydrothermal method in this study. The obtained samples were characterized by XRD, Raman, SEM, BET, XPS, DRS, PL, and EIS. The results revealed that Ti O Si bond formed between TiO 2 and the surface of muscovite, and the hexavalent W 6+ entered the TiO 2 crystal lattice to substitute the tetravalent Ti 4+ . Compared with the undoped M/TiO 2 , the absorption edge of W-doped samples exhibited a redshift, and the separation efficiency of the photo-induced carriers was improved. The highest photocatalytic activity was achieved when the doping amount of W was 0.5%, and the degradation ratio of methyl orange (MO) reached 98.4% after simulated solar light irradiation for 120 min. This research can provide a novel strategy to prepare highly efficient and stable TiO 2 -based photocatalytic materials.