Synthesis and visible-light photocatalytic property of spinel CuAl2O4 for vehicle emissions

Photodegradation of vehicle emissions is a promising approach for dealing with atmospheric pollution in road tunnels. In this research, copper aluminate nanoparticles (CuAl2O4) were prepared by the sol-gel method using copper nitrate, aluminum nitrate, and citric acid as precursor materials. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis spectroscopy to validate their structure, surface morphology, and optical properties, respectively. The XRD and SEM results confirm that the CuAl2O4 powder has a particle size of 20-37 nm and exhibits a spinel-type structure. The upper limit of the stimulation wavelength in the UV-Vis diffuse reflectance spectrum is located at 725 nm with a band gap (Eg) of about 1.50 eV, which is suitable for effective visible-light degradation. Photocatalytic performance of the CuAl2O4 nanoparticles was analyzed by investigating the effects of light source, calcination temperature, and catalyst loading amount on the degradation of vehicle emissions (CO, HC, and NO). Best results were obtained under fluorescent light irradiation by CuAl2O4 nanoparticles calcined at 700 degrees C. The optimum catalyst amount for decomposing CO, HC, and NO were determined as 0.5 g, 0.5 g, and 2 g, respectively. Overall, the photocatalytic performance study verifies that spinel CuAl2O4 photocatalyst is a valuable material for next-generation technologies aimed at reducing harmful emissions from vehicles.

Automated summary

In this study, copper aluminate nanoparticles (CuAl2O4) were synthesized using the sol-gel method and validated for their structure, morphology, and optical properties. The CuAl2O4 powder exhibited a particle size of 20-37 nm and a spinel-type structure. With a band gap of 1.50 eV, the CuAl2O4 nanoparticles showed potential for effective visible-light degradation. Further analysis on the photocatalytic performance revealed that fluorescent light irradiation with CuAl2O4 nanoparticles calcined at 700 degrees C yielded the best results in degrading vehicle emissions (CO, HC, and NO).