Synthesis and characterizations of Ni-SnO₂-TiO₂ nanocomposite for photocatalytic application

A first attempt was made to synthesize a Ni-SnO₂-TiO₂ nanocomposite by a one-pot simple synthetic method. A [Ni(im)₆]Cl₂ precursor complex is preferably adsorbed on the solid surface forming nanocomposite: complex adduct, it simultaneously becomes a surface species (Ni-SnO₂-TiO₂). In this investigation, it has been found that surface interaction of nickel complex ions lead to the formation of surface species that are identified by XRD, FTIR, UV–vis DRS, SEM, EDX, HRTEM, XPS, and XANES analyses. The metal-loaded metal oxide coupled semiconductor solids find their applications as catalysts and in advanced electronics. We demonstrate the dopant induced changes in electronic density of states using DFT VASP calculations. The photocatalytic property of Ni-SnO₂-TiO₂ sample was tested, and the results showed that a small amount of nickel surface co-doped SnO₂-TiO₂, formed an anatase–rutile-cassiterite mixed phases with surface defects or oxygen vacancies, and had improved the photocatalytic activity. The organic model pollutant of Azo dye and methyl orange degradation property of TiO₂ photocatalyst under visible light irradiation has greatly enhanced after the introduction of Ni into the SnO₂-TiO₂ surface matrix. This study points out a potential way to develop new and more active tin and nickel co-doped titania photocatalysts for organic pollutant degradation in water systems.