The construction and performance of photocatalytic-fuel-cell with Fe-MoS2/reduced graphene oxide@carbon fiber cloth and ZnFe2O4/Ag/Ag3VO4@carbon felt as photo electrodes

Approaches for Enhancing Wastewater Treatment of Photocatalytic Fuel Cells: A Review

Environmental pollution and energy crises have garnered global attention. The substantial discharge of organic waste into water bodies has led to profound environmental contamination. Photocatalytic fuel cells (PFCs) enabling the simultaneous removal of refractory contaminants and recovery of the chemical energy contained in organic pollutants provides a potential strategy to solve environmental issues and the energy crisis. This review will discuss the fundamentals, working principle, and configuration development of PFCs and photocatalytic microbial fuel cells (PMFCs). We particularly focus on the strategies for improving the wastewater treatment performance of PFCs/PMFCs in terms of coupled advanced oxidation processes, the rational design of high-efficiency electrodes, and the strengthening of the mass transfer process. The significant potential of PFCs/PMFCs in various fields is further discussed in detail. This review is intended to provide some guidance for the better implementation and widespread adoption of PFC wastewater treatment technologies.

Progress in the Preparation and Modification of Zinc Ferrites Used for the Photocatalytic Degradation of Organic Pollutants

Zinc ferrite is a type of photocatalytic material with high physicochemical stability, narrow band gap, high carrier separation efficiency, high porosity, and paramagnetism, which makes it easy to recover. Thus, zinc ferrite is widely used as a photocatalyst in water treatment. In this paper, the preparation principles as well as the advantages and disadvantages of typical methods used to prepare zinc ferrite including hydrothermal, co-precipitation, sol-gel, and other novel methods such as biosynthesis have been summarized. Modification methods such as elemental doping, composite formation, and morphological modification have been highlighted. Using these modification methods, the catalytic activity of zinc ferrite toward the photocatalytic degradation of organic pollutants in water has been enhanced. Biosynthesis is regarded as a promising preparation method that uses biological materials instead of chemical materials to achieve the large-scale preparation of zinc ferrite using low cost, energy efficient, and environmentally friendly processes. Meanwhile, the combination of multiple modification techniques to enhance the photocatalytic performance of zinc ferrite will be an important research trend in the future.

Construction of S-scheme CdS/g-C3N4 nanocomposite with improved visible-light photocatalytic degradation of methylene blue

Within moderate band gap, g-C₃N₄ and CdS are both promising visible light driven photocatalysts. However, their intrinsic high recombination rate of photo-induced electron-hole pairs along with the poor susceptibility in photocorrosion of CdS is main limitations hindering their practical application. In this study, the CdS/g-C₃N₄ composites with various weight ratios of CdS to g-C₃N₄ were solvothermal prepared from the dispersion of components, g-C₃N₄ and CdS, in ethanol. The physicochemical characterizations demonstrate the success in the fabrication of well-dispersed CdS nanoparticles in the g-C₃N₄ matrix. The enhanced photocatalytic activity of the g-C₃N₄/CdS composite over the degradation of methylene blue under visible light was ascribed to the effective photo-induced electron-hole separation via the step scheme (S-scheme) pathway in which the main contribution of high oxidative hydroxyl radicals (^•OH) was demonstrated. Furthermore, via S-scheme model, we also clarify the depletion of photo-induced holes on CdS which is ascribed as the reason for improvement in resistance to photocorrosion of composites.