Facile synthesis of solar light-driven Z-scheme Ag2CO3/TNS-001 photocatalyst for the effective degradation of naproxen: Mechanisms and degradation pathways

Non-steroidal anti-inflammatory drugs (NSAIDs) in the environment: Recent updates on the occurrence, fate, hazards and removal technologies

Non-steroidal Anti-inflammatory Drugs (NSAIDs) are extensively utilized pharmaceuticals worldwide. However, owing to the improper discharge and disposal practices, they have emerged as significant contaminants that are widely distributed in water, soils, and sewage sediments. This ubiquity poses a substantial threat to the ecosystem and human health. Consequently, it is imperative to develop rapid, cost-effective, efficient and reliable approaches for containing these substance in order to mitigate the deleterious impact of NSAIDs. This research provides a comprehensive review of the occurrence, fate, and hazards associated with NSAIDs in the general environment. Additionally, various removal technologies, including advanced oxidation processes, biodegradation, and adsorption, were systematically summarized. The study also presents a comparative analysis of the benefits and drawbacks of different removal technologies while interpreting challenges related to NSAIDs' removal and proposing strategies for future development.

Strategy for improvement of molecular oxygen activation capacity of PPECu by chlorine doping for water decontamination

The activation of molecular oxygen and generation of reactive oxygen species (ROS) play important roles in the efficient removal of contaminants from aqueous ecosystems. Herein, using a simple and rapid solvothermal process, we developed a chlorine-doped phenylethynylcopper (Cl/PPECu) photocatalyst and applied it to visible light degradation of sulfamethazine (SMT) in aqueous media. The Cl/PPECu was optimized to have a 2.52 times higher steady-state concentration of O2•- (3.62 × 10-5 M) and a 28.87 times higher degradation rate constant (0.2252 min-1) for SMT compared to pure PPECu. Further, the effectiveness of Cl/PPECu in treating sulfonamide antibiotics (SAs) in real water systems was verified through an investigation involving natural water bodies, SAs, and ambient sunlight. The energy band structure, DFT calculation and correlation heat map indicated that the addition of chlorine modulated the local electronic structure of PPECu, leading to an improvement in the electron-hole separation, enhanced the O2 activation, and promoted the generation of ROSs. This study not only puts forward innovative ideas for the eco-compatible remediation of environmental pollution using PPECu, but also sheds new light on the activation of oxygen through elemental doping.

Simplified synthesis of direct Z-scheme Bi2WO6/PhC2Cu heterojunction that shows enhanced photocatalytic degradation of 2,4,6-TCP: Kinetic study and mechanistic insights

For this work, we employed n-type Bi2WO6 and p-type PhC2Cu to formulate a direct Z-scheme Bi2WO6/PhC2Cu (PCBW) photocatalyst via simplified ultrasonic stirring technique. An optimal 0.6PCBW composite exhibited the capacity to rapidly photodegrade 2,4,6-TCP (98.6% in 120 min) under low-power blue LED light, which was 8.53 times and 12.53 times faster than for pristine PhC2Cu and Bi2WO6, respectively. Moreover, electron spin resonance (ESR), time-resolved PL spectra, and quantitative ROS tests indicated that the PCBW enhanced the separation capacity of photocarriers. It also more readily associated with dissolved oxygen in water to generate reactive oxygen species (ROS). Among them, the ability of PCBW to produce ·O2- in one hour was 12.07 times faster than for pure PhC2Cu. In addition, the H2O2 formation rate and apparent quantum efficiency of PCBW are 10.73 times that of PhC2Cu, which indicates that PCBW not only has excellent photocatalytic performance, but also has outstanding ROS production ability. Furthermore, Ag photodeposition, in situ X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations were utilized to determine the photogenerated electron migration paths in the PCBW, which systematically confirmed that Z-scheme heterojunction were successfully formed. Finally, based on the intermediate products, three potential 2,4,6-TCP degradation pathways were proposed.

In Situ Coupling Carbon Defective C3N5 Nanosheet with Ag2CO3 for Effective Degradation of Methylene Blue and Tetracycline Hydrochloride

The development of novel catalysts for degrading organic contaminants in water is a current hot topic in photocatalysis research for environmental protection. In this study, C₃N₅ nanosheet/Ag₂CO₃ nanocomposites (CNAC-X) were used as efficient photocatalysts for the visible-light-driven degradation of methylene blue (MB), and tetracycline hydrochloride (TC-HCl) was synthesized for the first time using a simple thermal oxidative exfoliation and in situ deposition method. Due to the synergistic effect of nanosheet structures, carbon defects, and Z-scheme heterojunctions, CNAC-10 exhibited the highest photocatalytic activity, with photodegradation efficiencies of 96.5% and 97.6% for MB (60 mg/L) and TC-HCl (50 mg/L) within 90 and 100 min, respectively. The radical trapping experiments showed that ·O₂^- and h⁺ played major roles in the photocatalytic effect of the CNAC-10 system. Furthermore, intermediates in the photodegradation of MB and TC-HCl were investigated to determine possible mineralization pathways. The results indicated that C₃N₅ nanosheet/Ag₂CO₃ photocatalysts prepared in this work could provide an effective reference for the treatment of organic wastewater.

Plasmonic Ag nanoparticles decorated copper-phenylacetylide polymer for visible-light-driven photocatalytic reduction of Cr(VI) and degradation of PPCPs: Performance, kinetics, and mechanism

The development of efficacious photocatalysts for the elimination of contaminants in water remains a challenge. Herein, a promising Ag nanoparticles-decorated copper-phenylacetylide (Ag/PhC₂Cu) plasmonic photocatalyst was fabricated for the reduction of hexavalent chromium (Cr(VI)) and degradation of pharmaceutical and personal care products (PPCPs). Typically, the optimized 5Ag/PhC₂Cu could rapidly reduce Cr(VI) (98.1% within 12 min), and degrade norfloxacin (NOR) (100% within 40 min) with a 56.2% mineralization rate under visible light. The superior photocatalytic activity of Ag/PhC₂Cu was attributed to the synergistic effects of the highly reducing photoinduced electrons conferred by the PhC₂Cu (-1.98 eV), and Ag nanoparticles in promoting photocarrier separation and enhancing solar-energy-conversion efficiencies. Subsequently, the photocatalytic reaction mechanism of Ag/PhC₂Cu was investigated. It was found that e^- and O₂^•- were the main reactive species for Cr(VI) reduction, while O₂^•- and h⁺ were primarily responsible for the degradation of NOR. Of note, the Ag/PhC₂Cu system could effectively generate H₂O₂ and partially decomposed it to •OH, which might be involved in NOR mineralization. This study not only demonstrates a highly active photocatalytic system for the remediation of environmental pollution and sustainable solar-to-chemical energy conversion, but contributes to the future exploration of multifunctional plasmonic photocatalysts.

In situ construction of a direct Z-scheme CdIn2S4/TiO2 heterojunction for improving photocatalytic properties

Direct Z-scheme photocatalytic systems driven by visible light to eliminate organic pollutants in wastewater have become important scientific tools in the field of photocatalysis.