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In this study, fly ash cenospheres (FACs), characterized by their floating properties and inherent photocatalytic activity, were used as a carrier to support ZnFe2O4 material and doped with conductive polymer polypyrrole (PPy) to prepare a novel ternary PPy–ZnFe2O4/FACs (PPy–ZF) composite catalyst. X-ray diffraction, Fourier transform infrared spectroscopy, TEM, and scanning electron microscopy were used to characterize the structure, morphology, and optical properties of the samples prepared. In particular, a 20 mg/L methyl orange (MO) solution at pH 4 was given 0.075 g of PPy–ZF catalyst to add, and after 30 min of dark adsorption, followed by irradiation for 180 min, 98.54% of the MO was removed. The material was also shown to have good stability and reusability through three cycles of use. Additionally, the material exhibited good photocatalytic activity for other dyes. The results of photocatalytic experiments showed their significantly enhanced photocatalytic activity toward MO, which was mainly attributed to the synergistic effect of PPy and ZnFe2O4 on the surface of FACs, leading to a high separation efficiency and a low rate of photogenerated charge complexation. In addition, cyclic tests demonstrated the stability and reusability of the composite. The leading role in the photocatalytic degradation of MO was demonstrated by the radical trapping experiment, which showed ·O2− and h+. The present study can significantly improve the photocatalytic performance of the floating materials of ZnFe2O4/FACs, which is beneficial to solve the current energy crisis and environmental pollution problems. It has certain reference significance to solve the problems of environmental pollution, waste recycling, and catalyst recycling in the future. [ABSTRACT FROM AUTHOR]

In this experiment, a novel heterostructured nano-TiO2/LaMnO3 composite photocatalyst was prepared by the sol–gel method, and the crystalline shape, morphology and photoresponse of the samples were analysed by combining XRD, FI-IR, SEM, TEM, BET, XPS, UV-Vis and PL characterization techniques, and the effects of different composite ratios, catalyst dosage, ammonia–nitrogen aqueous concentration and pH on the photocatalysis of the photocatalytic degradation of ammonia–nitrogen were investigated by combining with kinetic simulations. The results showed that T/LMO has a polyhedral shape with a microporous structure, a particle size of about 30 μm, and a band gap of 2.82 eV. After irradiation with a 25 W, 254 nm UV lamp for 3 h, T/LMO (1 : 2) could exhibit a 61.15% degradation rate in 100 mL NH4Cl solution with a mass concentration of 75 mg L−1 and pH 5, the degradation rate was still 52.5% after three times of recycling, the degradation products were mainly non-toxic nitrate nitrogen and nitrogen gas, and it was also experimentally demonstrated that ˙O2− and ˙OH are active radicals that play an important role in the photocatalytic degradation process. Finally, the experimental results were verified in conjunction with the results of photoelectrochemical tests, demonstrating that the binary composite T/LMO is a Z-type heterojunction structure. With good performance of photocatalytic degradation of ammonia nitrogen, reduced electron–hole pair complexation, and an increased photogenerated carrier migration rate, this study provides some theoretical knowledge and experimental evidence for the practical application of novel photocatalysts in the removal of ammonia nitrogen from wastewater. [ABSTRACT FROM AUTHOR]

Ultrasonic assisted hydrothermal and calcination methods were used to prepare type II heterojunction ZnBi2O4/g-C3N4 (ZBN) photocatalysts. The crystal structures, elemental compositions, morphologies and optical properties of the prepared monomer and heterojunction photocatalysts were characterized. The photocatalytic degradation efficiency of acid red B reached 95% in 180 min under UV irradiation, which was 1.82 and 1.44 times higher than that of g-C3N4 and ZnBi2O4, respectively, and the reaction rate constants were increased from 0.004 min−1 and 0.005 min−1 to 0.015 min−1. ZBN exhibited high photocatalytic activity, and the enhancement of activity can be attributed to the construction of the type II heterostructure and reduced carrier recombination. The degradation experiments of carmine, AO7, MO, MB and RhB showed that the composite ZBN had a better degradation effect on different dyes. The results of radical trapping experiments and EPR tests showed that ˙O2− plays a crucial role in the photocatalytic degradation of acid red B. Finally, the mechanism of the photocatalytic degradation of acid red B by ZBN was investigated by combining EPR, VB-XPS and radical trapping experiments. [ABSTRACT FROM AUTHOR]

Photocatalysis has attracted much attention because it can decompose water to produce hydrogen or reduce carbon dioxide to CH3OH, CH4 or other chemical materials. In this study, the MnFe2O4/g-C3N4 composite was fabricated by the co-precipitation method. Various techniques were used to characterize the MnFe2O4/g-C3N4 composite, including, FT-IR, Raman, XRD, SEM, EDS, and UV–Vis. Under UV light, the catalytic performance of MnFe2O4/g-C3N4 was tested by decomposing rhodamine B (Rh B). According to the findings, the catalyst is a typical spinel structure material with an excellent light response in 250–800 nm wavelength. The MnFe2O4/g-C3N4 composite catalyst can degrade over 82% of Rh B in 150 min. Cyclic experiments show that MnFe2O4/g-C3N4 has long-term stability for Rh B. Because of its heterojunction structure, photogenerated electrons from g-C3N4 surfaces may easily move to MnFe2O4, which can substantially increase photoelectron-hole pair separation. The use of the MnFe2O4/g-C3N4 compound as photocatalysts for the degradation of Rh B is evidenced by these findings. [ABSTRACT FROM AUTHOR]

In this study, zinc ferrate (ZnFe2O4) and polyaniline (PANI) were coated on the surface of FAC by hydrothermal and in situ polymerisation using the floating property of fly ash cenospheres (FAC) to form PANI‐ZnFe2O4/FAC composites. Compared with other reference materials, the PANI‐ZnFe2O4/FAC material not only solves the problem of less easy recycling, but also has significantly enhanced photocatalytic activity for methylene blue (MB). The significant increase in catalytic efficiency is attributed to the synergistic effect of PANI and ZnFe2O4 on the FAC surface resulting in efficient separation and low photogenerated charge complexation rates. In addition, cycling tests have shown the material to be stable and reusable. Active species capture experiments show that ⋅O2− and h+ play a dominant role in the reaction system. [ABSTRACT FROM AUTHOR]

The most characteristic feature of membranous nephropathy (MN) is the presence of subepithelial electron dense deposits and the consequential thickening of the glomerular basement membrane. There have been great advances in the understanding of the destiny of immune complexes in MN by the benefit of experimental models represented by Heymann nephritis. Subepithelial immune complexes are formed in situ by autoantibodies targeting native autoantigens or exogenous planted antigens such as the phospholipase A2 receptor (PLA2R) and cationic BSA respectively. The nascent immune complexes would not be pathogenic until they develop into immune deposits. Podocytes are the major source of autoantigens in idiopathic membranous nephropathy. They also participate in the modulation and removal of the immune complexes to a large extent. The balance between deposition and clearance is regulated by a wide range of factors such as the composition and physicochemical properties of the immune complexes and the complement system. Complement components such as C3 and C1q have been reported to be precipitated with the deposits whereas a complement regulatory protein CR1 expressed by podocytes is involved in the phagocytosis of immune complexes by podocytes. Podocytes regulate the dynamic change of immune complexes which is disturbed in membranous nephropathy. To elucidate the precise fate of the immune complexes is essential for developing more rational and novel therapies for membranous nephropathy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Xu, Hu, Sun, Zhao, Zhang, Yang and Lu.)