Solar photocatalytic degradation of thidiazuron in Yangtze River water matrix by Ag/AgCl-AC at circumneutral condition

Fabrication of Fe-BTC on aramid fabrics for repeated degradation of isoproturon

Catalytic degradation is a promising and ideal technology in environmental remediation. Among them, catalytic oxidation and photocatalysis respectively based on catalysts and photocatalysts both trigger broad interests because of their high removal activity. However, the reusability of the powder catalysts still faces substantial challenges. Here, a simple strategy is proposed to load Fe-BTC catalyst on aramid fabrics (AF) to construct Fe-BTC MOF @ aramid fabric (Fe-BTC@AF) composite materials with layer-by-layer in situ self-assembly methods. The experimental results illustrated that 98% isoproturon could be removed by Fe-BTC@AF₂₀ with oxidant H₂O₂, while the single Fe-BTC@AF₂₀ could photo-degrade 99% isoproturon within 7 h. Meanwhile, it could sustain a high degradation rate of more than 80%, even if it had gone through 5 degradation cycles. Thus, the Fe-BTC@AF composite has a significant advantage in the recycling ability for degradation of isoproturon, which will have potential applications in the efficient removal of organic contaminants in water.

Wastewater Purification and All-Solid Z-Scheme Heterojunction ZnO-C/MnO2 Preparation: Properties and Mechanism

Unlike many studies on the preparation of Z-scheme heterojunctions by doping precious metals, in this paper we first prepared a core-shell material obtained by C doping in ZnO and then composite with MnO2 to form a heterojunction; that is, a low-cost and highly catalytic ternary composite catalyst was prepared by a simple hydrothermal reaction. Meanwhile, a large amount of experimental data have enabled the heterostructure type as well as the mechanism of photocatalytic performance to be fully demonstrated. It is proven that C as an intermediate medium achieves electron transport while making up the deficiency of ZnO, and constitutes an all-solid state Z-scheme heterojunction, which enables the rapid transfer of photogenerated electron pairs and visible light irradiation to the stream to improve the photocatalytic performance of the composite photocatalyst. In terms of examination of degradation performance, this catalyst showed a high photodegradation rate of tetracycline hydrochloride (TC) of 92.6% within 60 min, and the surface ZnO-C/MnO2 catalysts also showed good degradation effect on practical petrochemical wastewater in CODcr degradation experiments.

Heterojunction formation between AgNbO3 and Co3O4 for full solar light utilization with improved charge-carrier separation

In the present study, the charge-carrier recombination of visible light active perovskite silver niobate (AgNbO₃) was reduced by forming heterojunction with Co₃O₄ through simple impregnation and calcination route. The loading percentage of Co₃O₄ was varied as 2, 5, and 10 wt.%. The XRD study revealed reduced interlayer spacing in the composite due to the replacement of the bigger Ag⁺ ions by the smaller Co²⁺ and Co³⁺ ions of Co₃O₄. It was observed that the light harvesting efficiency of the materials was increased with increased loading of Co₃O₄. The TEM and XPS analysis confirmed the presence of Ag nanoparticles over the perovskite in the composite. The electrochemical analysis revealed enhanced charge-carrier number density and increased charge-carrier lifetime in the composite as a result of the presence of both silver and cobalt ions in the lattice. Further this enhanced charge-carrier separation of the composites was established through photocatalysis of Bisphenol-A under both solar and LED light. Charge-trapping study indicated *O₂^- and *OH as the major radicals involved and Z-scheme as the predominant charge transfer pathway for generation of these reactive oxygen species.

Immobilised rGO/TiO2 Nanocomposite for Multi-Cycle Removal of Methylene Blue Dye from an Aqueous Medium

This work presents the immobilisation of titanium dioxide (TiO2) nanoparticles (NPs) and reduced graphene oxide (rGO)-TiO2 nanocomposite on glass sheets for photocatalytic degradation of methylene blue (MB) under different radiation sources such as ultraviolet and simulated solar radiation. The TiO2 NPs and rGO-TiO2 nanocomposite were synthesised through a simple hydrothermal method of titanium isopropoxide precursor followed by calcination treatment. Deposition of prepared photocatalysts was performed by spin-coating method. Additionally, ethylene glycol was mixed with the prepared TiO2 NPs and rGO-TiO2 nanocomposite to enhance film adhesion on the glass surface. The photocatalytic activity under ultraviolet and simulated solar irradiation was examined. Further, the influence of different water matrices (milli-Q, river, lake, and seawater) and reactive species (h+, •OH, and e−) on the photocatalytic efficiency of the immobilised rGO/TiO2 nanocomposite was careful assessed. MB dye photocatalytic degradation was found to increase with increasing irradiation time for both irradiation sources. The immobilisation of prepared photocatalysts is very convenient for environment applications, due to easy separation and reusability, and the investigated rGO/TiO2-coated glass sheets demonstrated high efficiency in removing MB dye from an aqueous medium during five consecutive cycles.