Microwave Induced Inverse Spinel NiFe2O4 Decorated g-C3N4 Nanosheet for Enhanced Visible Light Photocatalytic Activity

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 °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.

Ultrasound-Assisted Hydrothermal Synthesis of SrSnO3/g-C3N4 Heterojunction with Enhanced Photocatalytic Performance for Ciprofloxacin under Visible Light

In this work, an SrSnO3/g-C3N4 heterojunction with different dosage of SrSnO3 was fabricated by an ultrasound-assisted hydrothermal approach and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible diffuse reflectance spectra (UV-Vis DRS), and photoluminescence spectroscopy (PL). Ciprofloxacin was adopted to assess the degradation performance, and the sample combined with 40% SrSnO3 eliminated 93% of ciprofloxacin (20 mg/L) within 3 h under visible light, which is 6.6 and 1.7 times greater than for SrSnO3 and g-C3N4, respectively. Furthermore, 85% CIP was extinguished after five cycles of a photocatalytic process. Ultimately, a possible photocatalytic mechanism was dissected.

Recent advancements of g-C3N4-based magnetic photocatalysts towards the degradation of organic pollutants: a review

Heterogeneous photocatalysis premised on advanced oxidation processes has witnessed a broad application perspective, including water purification and environmental remediation. In particular, the graphitic carbon nitride (g-C₃N₄), an earth-abundant metal-free conjugated polymer, has acquired extensive application scope and interdisciplinary consideration owing to its outstanding structural and physicochemical properties. However, several issues such as the high recombination rate of the photo-generated electron-hole pairs, smaller specific surface area, and lower electrical conductivity curtail the catalytic efficacy of bulk g-C₃N₄. Another challenging task is separating the catalyst from the reaction medium, limiting their reusability and practical applications. Therefore, several methodologies are adopted strategically to tackle these issues. Attention is being paid, especially to the magnetic nanocomposites (NCs) based catalysts to enhance efficiency and proficient reusability property. This review summarizes the latest progress related to the design and development of magnetic g-C₃N₄-based NCs and their utilization in photocatalytic systems. The usefulness of the semiconductor heterojunctions on the catalytic activity, working mechanism, and degradation of pollutants are discussed in detail. The major challenges and prospects of using magnetic g-C₃N₄-based NCs for photocatalytic applications are highlighted in this report.