Synthesis of Ni, N co-doped TiO2 using microwave-assisted method for sodium lauryl sulfate degradation by photocatalyst

A titanium dioxide (TiO 2 ) photocatalyst was modified with nickel (Ni) and nitrogen (N) in titanium tetra-isopropoxide (TTIP) as a precursor through a microwave-assisted method. The Ni and N dopants led to a decrease in the TiO 2 band gap and made it able to function with visible light irradiation. The results of X-ray diffraction analysis demonstrated that the crystalline size of Ni–N–TiO 2 was 13.275 nm in anatase form with a specific peak in 2 θ = 25.32°. Ni–N–TiO 2 was analyzed by scanning electron microscopy, which showed the smaller morphology and thin particles, and this was further supported by energy-dispersive X-ray data regarding the elemental composition of Ni and N being 4.50 and 2.39%, respectively. Fourier transform infrared spectroscopy results demonstrated the absorption spectrum in wavenumbers of 1197 and 1149 cm −1 , indicating an N–TiO 2 bond, a Ti–O bond at 648 cm −1 , and an Ni–O bond at 469 cm −1 . TiO 2 modified by Ni and N exhibited a decrease in the band gap at 1.95 eV, suggesting the Ni and N dopants successfully inserted onto the TiO 2 crystalline surface to be visualized with visible light. Photoactivity testing was carried out to degrade sodium lauryl sulfate surfactants under visible irradiation, where the degradation efficiency was 93.75%.