Exceptional photodecomposition activity of heterostructure NiTiO3-TiO2 catalyst

Mesoporous TiO2 mixed with NiTiO3 at various concentrations was synthesized by combining sol-gel and eco-friendly hydrothermal methods. The properties of the NiTiO3-TiO2 (NTO-Ti) photocatalyst were characterized using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy, Brunauer-Emmett-Teller adsorption, energy dispersive X-ray, and UV-vis absorption spectra techniques. The photocatalytic activity of NTO-Ti catalysts was assessed by way of the photodegradation of cinnamic acid (CA) under UV-A irradiation. The effects of the operating parameters, including catalyst dosage, airflow, and initial solution pH on the photodecomposition efficiency of CA were also investigated. Research results confirm that NTO-Ti heterostructure catalysts are synthesized in the crystalline phase with high crystallinity. Compared with pure TiO2, the NTO-Ti catalysts have a smaller particle size and average crystallite size (8.6-9.0 nm versus 34.8 nm) and lower band gap energy (3.02-3.08 eV versus 3.20 eV). The catalysts also enable a redshift in the absorption band from UV (lambda = 385 nm) to UV-A light (lambda = 404-412 nm). The study showed that the physicochemical and photochemical properties and the photocatalytic performance of the NTO-Ti catalysts are controlled by the NiTiO3 loading. NTO-Ti with NiTiO3 1.0 wt.% was found to maximize CA photodegradation. Under the most favorable conditions, CA removal of 82.8% was obtained after 120 min, which is higher than for pure TiO2 (68.7%) and NiTiO3 (3.8%) catalysts under the same conditions. (C) 2022 Vietnam National University, Hanoi. Published by Elsevier B.V.

Automated summary

Mesoporous TiO2 mixed with NiTiO3 at various concentrations was synthesized using a combination of sol-gel and eco-friendly hydrothermal methods. The resulting NTO-Ti photocatalyst exhibited improved physicochemical and photochemical properties compared to pure TiO2 and NiTiO3 catalysts, resulting in enhanced photocatalytic performance for the degradation of cinnamic acid under UV-A irradiation.