NIR-driven upconversion nanophotocatalyst based on hybrid inorganic-organic polyoxometalate for photodegradation of liquorice and biologically treated yeast extract industrial wastewater

Highlights: • Novel NIR-driven photocatalyst was synthesized and physicochemical properties were characterized. • Upconversion property of the photocatalyst was proved. • Mott-Schottky, Nyquist and Bode plots were studied. • Photocurrent and electrochemical properties were also investigated. • Photodegradation of liqourice and yeast extracted wastewater were optimized. Utilization of Near-infrared (NIR) or infrared light improve the efficiency of photodegradation by using lower energy but it has remained as a challenge yet. NIR light-driven nanocomposite containing organic heteropoly salt and TiO₂ has been synthesized by a two-step sol-gel/solvothermal method to extend the absorption range of the TiO₂ photocatalyst from UV to IR region. This photoactivity was proved by Tauc and photoluminescence plots. This compound has been well-characterized by XRD, SEM-EDX, PL, FTIR and EIS techniques. The composite structure can not only extend the absorption of TiO₂ but also consequently increase life-time of excited electron and hole, which improve the photocatalytic efficiency of the photocatalyst. The charge transfer resistance was also decreased compare with TiO₂ which was proved by Nyquist and Bode plots. Photocurrent generation was studied by photoelectrochemical investigation. Photodegradation of liqourice and biologically treated yeast extracted wastewater were also investigated with optimization of reaction conditions. The present work should be the rarely fundamental investigation on the utilization of NIR light-driven photocatalyst.