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The circular economy requires advanced methods to recycle waste matter such as ammonia, which can be further used as a fuel and a precursor of numerous value-added chemicals. Here, we review methods for the recovery of ammonia from wastewater with emphasis on biological and physicochemical techniques, and their applications. Biological techniques involve nitrification, denitrification, and anammox processes and the use of membrane bioreactors. Physicochemical techniques comprise adsorption, membrane filtration, ion exchange, chemical precipitation, ammonia stripping, electrochemical oxidation, photocatalytic oxidation, bioelectrochemical systems, and membrane hybrid systems. We found that nitrification and anammox processes in membrane bioreactors stand out for their cost-effectiveness, reduced sludge production, and energy efficiency. The use of struvite precipitation is an efficient, environmentally friendly, and recyclable method for ammonia removal. Membrane hybrid systems are promising for ammonia recovery, nutrient concentration, and wastewater treatment, with applications in fertilizer production and water purification. Overall, nitrogen removal ranges from 28 to 100%, and nitrogen recovery ranges from 9 to 100%. [ABSTRACT FROM AUTHOR]

The development of the oil industry and the fossil fuel economy has historically improved the quality of life for many people, but it has also led to significant environmental degradation. As a response, the concept of 'sustainable development' has gained prominence recently, emphasizing the importance of balancing economic progress with environmental protection. Among the many environmental challenges we face today, preserving water resources is one of the most pressing. To tackle this issue, researchers are focusing on strategies to reduce water consumption and enhance the efficiency of wastewater treatment. In this context, the present review explores recent advancements in a novel coupled treatment process that integrates adsorption in activated carbon fiber (ACF) and photocatalytic oxidation using TiO2 to remove micropollutants from wastewater. This innovative approach would allow for the in situ and continuous regeneration of ACF with TiO2 photocatalysis, increasing the oxidative degradation efficiencies of the supported semiconductor thanks to the adsorbent material, all under the possibility of a durable and low-cost process using solar radiation. In addition, this is vital for meeting regulatory standards, protecting aquatic ecosystems, and safeguarding human health. [ABSTRACT FROM AUTHOR]

Photocatalytic selective oxidation of C(sp3)─H bonds into valuable carbonyl compounds offers a promising approach to advance green organic synthesis and contribute to a more sustainable chemical industry. However, significant challenges remain due to the low efficiency of photocatalysts, primarily caused by insufficient charge separation and the limited ability of intermixed surface redox‐active sites to precisely capture photoinduced charge carriers. Here, a PEA2PbBr4/CeO2 (PPB/CeO2) p‐n heterojunction is designed and fabricated. Experimental characterizations and theoretical calculations reveal that a strong internal electric field (IEF) is formed at the interface within the p‐n heterojunction, which drives targeted accumulation of holes on PPB and electrons on CeO2. Importantly, CeO2 displays superior oxygen affinity facilitating O2 reduction, while PPB validates stronger adsorption and activation capability to toluene molecule promoting C─H bond dissociation. In this context, the photoinduced electrons and holes are directionally separated and transported to the decoupled reduction and oxidation sites in the PPB/CeO2, thereby significantly accelerating the aerobic oxidation of C(sp3)─H bonds. Toward photocatalytic oxidation of model substrate toluene, the optimized PPB/CeO2‐5% composite exhibits a toluene conversion rate of 10 050 µmol g−1 h−1, which is nine times enhanced in comparison with blank PPB (1160 µmol g−1 h−1). [ABSTRACT FROM AUTHOR]

Photocatalytic oxidation was a green and sustainable method for conversing the biomass derived platform molecule 5‐hydroxymethylfurfural (HMF) to high value‐added 2,5‐diformyfuran (DFF). In this work, both graphitized carbon nitride (g‐C3N4) and sulfur doped g‐C3N4 (S‐g‐C3N4) were fabricated, characterized and applied in the photocatalytic conversion of HMF. Accelerated separation of the photogenerated charge carriers was obtained on S‐g‐C3N4 with higher production of reactive oxygen species (ROS) including singlet oxygen (1O2) and superoxide radicals (⋅O2−), whereas relative higher HMF conversion rate and DFF selectivity were achieved on g‐C3N4. The mechanism investigation suggested that the contradictory phenomena may be caused by the stronger binding affinity of HMF on S‐g‐C3N4 compared with g‐C3N4 based on the temperature‐programmed desorption (TPD) measurement and theoretical calculation. The strong adsorption of HMF on the catalyst surface was unfavorable for desorption of the intermediates, and led to the accumulation of large number of carbon‐centered radicals. Part of these radicals may react with each other to generate polymerization products and block the active sites of the catalyst, resulted in the low conversion efficiency of HMF and DFF selectivity finally. This work provided a new sight and valuable theoretical and experimental basis for developing efficient photocatalysts for biomass conversion. [ABSTRACT FROM AUTHOR]

The removal of volatile organic compounds (VOCs) is crucial in environmental research due to their harmful effects. Among diverse technologies for VOCs' removal, catalytic oxidation is a continuously advancing and useful technology with high treatment efficiency and low energy consumption. Recently, metal oxide catalytic oxidation is valued for the huge surface area and stable framework of the specific catalysts and its broad applicability. This review systematically summarizes recent application of several commonly used metal oxide catalysts, including their catalytic properties, influencing factors and the mechanisms. It is helpful in the scientific design and preparation of novel metal oxide catalysts for VOCs' degradation. [ABSTRACT FROM AUTHOR]

Anesthetic gases enter the environment primarily through patient exhalation and venting from scavenging systems directly into the atmosphere. Emissions of halogenated anesthetic gases like halothane, isoflurane and sevoflurane are of concern due to their high global warming potential, highlighting the need to mitigate their environmental impact. Photocatalytic oxidation has been proposed as a potential option for emission control and indoor air treatment, but data on its use for various halogenated anesthetics is very limited. In this work, photocatalytic oxidation efficiency for the degradation of halothane was studied by varying the method for catalyst support and catalyst mass loading. Approximately 99.9% of halothane (1296 mg/m3) in air was degraded with a TiO2 photocatalyst under UVC light (254 nm) in 35 min in a recirculating batch photoreactor. The optimized conditions for halothane demonstrated a similar although faster photocatalytic degradation efficiency for isoflurane (99.8% in 20 min, 911 mg/m3) and sevoflurane (>98% in 10 min, 847 mg/m3). The results presented here suggest that a UV–photocatalysis is a promising technique to treat such anesthetic gases before being released into the environment by scavenging systems, although significant work remains to identify the potential by-products and optimal photoreactor designs for efficient long-term operation. [ABSTRACT FROM AUTHOR]

Antibiotics, widely used pharmaceuticals, enter wastewater treatment systems and ultimately the aquatic environment through the discharge of wastewater from residential areas, hospitals, breeding farms, and pharmaceutical factories, posing potential ecological and health risks. Due to the misuse and discharge of antibiotics, the spread of antibiotic resistance genes (ARGs) in water bodies and significant changes in microbial community structure have direct toxic effects on aquatic ecosystems and human health. This paper summarizes the occurrence of antibiotics in wastewater treatment systems and their ecological and health risks, focusing on the impact of antibiotics on aquatic microorganisms, aquatic plants and animals, and human health. It points out that existing wastewater treatment processes have poor removal capabilities for antibiotics and even become an important pathway for the spread of some antibiotics. In terms of detection technology, the article discusses the application of immunoassays, instrumental analysis, and emerging sensor technologies in detecting antibiotics in sewage, each with its advantages and limitations. Future efforts should combine multiple technologies to improve detection accuracy. Regarding the removal methods of antibiotics, the paper categorizes physical, chemical, and biodegradation methods, introducing various advanced technologies including membrane separation, adsorption, electrochemical oxidation, photocatalytic oxidation, and membrane bioreactors. Although these methods have shown good removal effects in the laboratory, there are still many limitations in large-scale practical applications. This paper innovatively takes urban wastewater treatment systems as the entry point, systematically integrating the sources of antibiotics, environmental risks, detection technologies, and treatment methods, providing targeted and practical theoretical support and technical guidance, especially in the removal of antibiotics in wastewater treatment, on a scientific basis. Future efforts should strengthen the control of antibiotic sources, improve the efficiency of wastewater treatment, optimize detection technologies, and promote the formulation and implementation of relevant laws and standards to more effectively manage and control antibiotic pollution in the aquatic environment. [ABSTRACT FROM AUTHOR]

In this study, zinc oxide (ZnO) nanoparticle was fabricated using the extract of Olive leaves (referred as ZnO NPs), using the green synthesis process, and then explores its ability for photodegradation of different concentrations of sulfosulfuron herbicide (10, 20, 40, and 80) mg/L under visible light in batch mode system at pH of 6.8 and one g/L of ZnO NPs. Morphological and structural properties of the synthesized ZnO NPs have been characterized using X-ray diffraction (XRD), fourier transform infrared (FTIR), brunauer Emmett Teller (BET), vibrating sample-magnetometer (VSM), transmission electron microscope (TEM), scanning electron microscopy (SEM). The finding confirms that the maximum removal efficacy reached 82.08% under optimum conditions of 10 mg/L of sulfosulfuron Herbicide concentration, and 90 min. In addition, the reaction followed a first-order kinetics model with R² > 96. The study also showed that ZnO NPs could be used as a catalyst for four cycles of photocatalytic oxidation of organic contaminants before losing its effectiveness. According to the finding of this study, ZnO NPs has an acceptable efficiency in the elimination of herbicide, as their relatively simple synthesis, could be a suitable catalyst for the degradation and elimination of pharmaceutical residues. [ABSTRACT FROM AUTHOR]

Bismuth vanadate has been reported as a promising active semiconductor for visible light harvesting. However, the rapid recombination of charge carriers has limited its photocatalytic properties. As an alternative route to treat contaminated water containing cyanide ions, photoactivated BiVO4 in combination with ozone has been investigated. BiVO4 photocatalysts were synthesized by microwave-assisted hydrothermal method, as well as by sol–gel, obtaining the monoclinic crystalline structure and a band gap of ~ 2.5 eV by XRD and UV–Vis DRS. The morphological analysis, elemental chemical composition, BET surface area, stability, and photoluminescence characteristics were carried out for both samples. Although the majority composition belongs to BiVO4, the presence of secondary phases was confirmed by XPS. The BiVO4 obtained by sol–gel (sol–gel BVO) exhibited superior photocatalytic performance with a lower reaction time (15 min) to oxidize free cyanide under visible-light radiation in combination with ozone. The degradation kinetics is described by pseudo-zero-order kinetics, and the rate constant (k0) of BiVO4 synthesized by microwave-assisted hydrothermal method was found to be the lower of the two. The high efficiency of the photocatalytic ozonation for the removal of free cyanide can be ascribed to a combination of two oxidation systems and the synergy of both processes. [ABSTRACT FROM AUTHOR]

In Janus photocatalysts, intrinsic dipole (P) plays an important role in the separation of photogenerated carriers and photocatalytic activity for water splitting. However, effectively switching the direction of the P vector between different surfaces is still an open issue. Based on first-principles calculation, we find that the P vector relies on charge distribution, while the distribution of the conduction band maximum-distributed reduction reaction surfaces (Sc) and valence band minimum-distributed oxidation surfaces (Sv) depends on the orbital hybridization in GaOI-based Janus. The direction of the P vector can be switched between Sc and Sv by substituting a metal or halogen atomic layer. The P vector in the direction from Sc to Sv releases bandgap limitation, broadens the light absorption range, and improves high carriers' mobility and solar-to-hydrogen efficiency (STH) efficiency, while the P vector pointing from Sv to Sc hinders the photocatalytic activity of GaOI-based Janus. Based on the investigation of STH efficiency and redox reactions, GaInOI is found to be a potential photocatalyst for overall water splitting. The stability of the Janus is studied by ab initio molecular dynamics and phonon diffusion spectrum. Current work proposes that switching the direction of the P vector between Sv and Sc is a potential route to regulate the band structure, optical absorption, and photocatalytic activity in GaOI-based Janus. [ABSTRACT FROM AUTHOR]

[Display omitted] Altering the electron distribution within a catalyst to manipulate internal charge migration pathways is an effective strategy for achieving high efficiency in carrier separation and migration, which is essential for the advancement of photocatalytic water oxidation technologies. We have employed atomic layer deposition (ALD) to construct a BiFeO 3 /CuO (BFO/CuO) heterojunction with a specific CuO thickness, resulting in a Z-type junction (BFO/CuO50) characterized by a robust internal electric field. This junction facilitates the spatial separation of charge carriers, thereby enhancing their migration efficiency. Moreover, we introduced cobalt-based co-catalysts onto the BFO/CuO50 surface, leading to the creation of reactive centers that enrich holes, thus crafting a three-dimensional composite with superior carrier excitation and separation capabilities. The optimized catalyst, denoted as BFO/CuO50@Co 0.1% , demonstrated to produce oxygen at a rate of 1.53 mmol g−1 h−1 and remarkable stability. These findings provide the direction for research and design in the domain of photocatalytic oxygen evolution, offering a guidance for the development of complete water-splitting ferroelectric catalysts which enhance the generation and separation of photo-driven charge carriers. [ABSTRACT FROM AUTHOR]

[Display omitted] Heterointerface engineering is an effective strategy to design and construct high-performance photocatalysts. Herein, polyaniline (PANI) nanoparticles and ZnTi layered double hydroxide (ZnTi-LDH) nanosheets were integrated to form organic–inorganic heterostructure (PANI/LDH) via d – π electronic coupling using in-situ polymerization for photocatalytic oxidation/reduction towards tetracycline (TC) and Cr(VI). The photocatalytic activity was closely related to feed amount of aniline (Ani) in the polymerization process, which the abundant PANI nanoparticles were evenly distributed on the surface of ZnTi-LDH nanosheets at the proper Ani feed amount, and thus reinforced d –π electronic coupling at the organic–inorganic interfaces more efficiently. Density functional theory calculations further verified the existence of d –π overlap at the PANI/LDH heterointerface. The strong d –π coupling boosted charge separation and transfer to improve photocatalytic efficiency. As a result, the optimal PANI/LDH (0.3) exhibited outstanding photocatalytic activities with 97.8 % Cr(VI) reducing rate and 87.8 % TC removal rate in the single Cr(VI) and TC system, as well as high simultaneous removal rate of Cr(VI) and TC in TC/Cr(VI) coexistence system, respectively. Subsequently, the photocatalytic enhanced mechanisms were put forward to remove Cr(VI) and TC under visible-light. Finally, the aquatic toxicity of the photolytic products was evaluated using Chlorella sp. as an ecological indicator, showing that the PANI/LDH had a notable detoxification efficiency of TC and Cr(VI). [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface cobalt-doped TiO 2 were prepared for the photocatalytic selective oxidation of glycerol to liquid hydrogen carriers. • The optimized system exhibited 95 % conversion of glycerol and 78 % yield of liquid hydrogen carriers. • The photo(electro)chemical analyses demonstrated that the introduction of the Co species could inhibit carrier recombination. • In-depth investigations have shown that photogenerated holes and superoxide radicals are the main active species. Glycerol is one of the most important biomass platform compounds that is a by-product of biodiesel production, and the selective cleavage of the C C bond of glycerol to produce liquid hydrogen carriers (i.e., formic acid and formaldehyde) offers a viable strategy to alleviate the currently faced energy shortages. However, the harsh reaction conditions, long reaction times, poor yields of liquid hydrogen carriers, and the tendency of peroxidation to carbon dioxide (CO 2) make the selective C C bond cleavage of glycerol more challenging. Herein, we report the selective C C bond cleavage of glycerol to formic acid and formaldehyde using surface cobalt (Co)-doped titanium dioxide (TiO 2) under light irradiation and ambient conditions. The optimized system exhibits a high conversion of glycerol (95 %) and the yield of liquid hydrogen carriers reaches 78 % (formic acid, 57 %; formaldehyde, 21 %) in 8 h, effectively preventing their peroxidation to CO 2. The outstanding photocatalytic performance is mainly attributed to the introduction of Co species and oxygen vacancies that promote the separation of photogenerated charges and holes and provide more adsorption sites for oxygen which are electron acceptors, respectively. In-depth investigations have shown that photogenerated holes and superoxide radicals are the main active species in this reaction. This work presents an effective and promising strategy for the efficient utilization of biomass resources. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C3N4) is a visible light catalyst with considerable potential, offering broad application prospects in fields such as pollutant decomposition. In this study, we systematically investigated the geometric, electronic, and optical properties of B-doped, P-doped, and B/P co-doped g-C3N4 using first-principles methods. We also examined the adsorption effects of g-C3N4 on emerging oxidants, periodate (PI) and Peroxymonosulfate (PMS). The results showed that B/P co-doping significantly narrowed the band gap of g-C3N4 to 0.39 eV, transforming it into a direct band gap structure. Additionally, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) exhibit enhanced delocalization, particularly over the bridging N1 atoms, which improved carrier mobility. Compared to pristine g-C3N4, the optical absorption demonstrated a more favorable response to visible light. Notably, the B/P co-doping system significantly increased the adsorption capacity of g-C3N4 for PI and PMS, promoting the generation of reactive species such as singlet oxygen (1O2), sulfate radicals (SO·4−), and hydroxyl radicals (·OH), providing a favorable pathway for the degradation of pollutants in water. In summary, B/P co-doping significantly enhances the photocatalytic performance of g-C3N4, establishing it as a highly efficient, eco-friendly, and cost-effective metal-free photocatalyst with great potential for advanced oxidation processes under visible light in wastewater treatment. [ABSTRACT FROM AUTHOR]

Exploring heterojunction formation between conjugated organic polymer and metal‐based semiconductors with promoted charge transfer and efficient spatial charge separation has proven to be quite successful in reinforcing photocatalytic wastewater treatment. Focusing on the removal of sulfonamide antibiotics from water, herein, we report BaTiO3/I@g‐C3N4 Z‐scheme heterojunction photocatalyst for degradation of sulfamethazine (SMZ) pollutant. The optimized heterojunction 25ICN/BT exhibits superior 94.5% removal of SMZ in 90 min, which is nearly 11 and 5 times faster than BT and pristine I@g‐C3N4 under visible light. The good repeatability of 25BT/ICN was proved by four‐cycle experiments. The remarkable improvement in photocatalytic activity was due to effective Z‐scheme transfer, diminished recombination, high charge transfer capacity, and redox capability. This was ascertained by electrochemical experiments and photoluminescence measurements. Furthermore, the degradation intermediates formed during the photocatalytic oxidation of SMZ were detected via liquid chromatography‐mass spectrometry, and a suitable degradation pathway was suggested. The heterojunctions showed excellent performance in river, lake, and tap water and for other antibiotic pollutants. The radical quenching experiments and band structure analysis inferred •O2− radicals as main active species. This work lays down new perspectives on hierarchical heterostructures for the superior removal of noxious antibiotic contaminants. [ABSTRACT FROM AUTHOR]

The ternary chalcogenide ZnIn2S4 (ZIS) has been synthesized by a simple hydrothermal method in which the carcinogen thiacetamide, universally used as a precursor, has been, for the first time, replaced successfully with the harmless thiourea. ZIS has been used as photocatalyst for the partial oxidation of different aromatic alcohols to their corresponding aldehyde in water solution, under ambient conditions and simulated solar light irradiation. The photocatalytic performance of ZnIn2S4 was better than TiO2 P25. In the presence of ZIS for 4‐methoxybenzyl alcohol, piperonyl alcohol, and benzyl alcohol, a selectivity towards the corresponding aldehyde of 99 % for a conversion of 46 %, 75 % for a conversion of 81 %, and 87 % for a conversion of 25 %, respectively, was obtained. For the same alcohols a selectivity of 19 % for a conversion of 41 %, 19 % for a conversion of 13 %, and 16 % for a conversion of 26 %, was observed in the presence of TiO2 P25. [ABSTRACT FROM AUTHOR]

The synthesis of novel polyoxovanadates (POVs) has received considerable critical attention. Herein, two new POVs, {V12P8} (1) and {V16P8} (2), have been designed and synthesized based on phenylphosphonic acid (PhPO3H2) under solvothermal conditions. The structure of 2 is a 16-nuclearity POV composed of four rare zigzag {V4} secondary building units (SBUs). To the best of our knowledge, 2 is the first POV synthesized with PhPO3H2 including this zigzag SBU, which is also very rare among all POVs. Moreover, 2 is the highest-nuclearity isopolyoxovanadate (IPOV) synthesized using PhPO3H2 as the only organic ligand so far. The photocatalytic properties of 1 and 2 were studied under visible light. Both 1 and 2 demonstrate good performance in photocatalytic oxidation of 1,5-dihydroxynaphthalene (1,5-DHN). Compound 1 also has a photocatalytic effect on MB degradation, with 87% of MB degradation within 8 minutes. [ABSTRACT FROM AUTHOR]

Double Z-scheme Bi 2 S 3 /S-CN/Bi 2 O 3 heterojunction hollow nanotubes with defective structure were synthesized and exhibited efficient photocatalytic amine oxidation owing to the synergistic of each component, hollow nanotube structure, and unique defect-transit double Z-scheme heterostructure. [Display omitted] The rational design of Z-scheme heterojunction hybrid photocatalysts is considered a promising way to achieve high photocatalytic activity. In this study, a dual Z-scheme heterojunction with bismuth sulfide (Bi 2 S 3) nanorods and bismuth oxide (Bi 2 O 3) nanoparticles anchored Sulfur-doped carbon nitride (S-CN) nanotubes (Bi 2 S 3 /S-CN/Bi 2 O 3) is designed and fabricated through the ordinal metal ion adsorption, pyrolysis, and sulfidation processes using supramolecular rods as precursor. Compared with pristine Bi 2 S 3 , Bi 2 O 3 , and CN, the dual Z-scheme tube-shaped Bi 2 S 3 /S-CN/Bi 2 O 3 catalyst exhibited a significantly improved photocatalytic activity in amine oxidation. The optimized Bi 2 S 3 /S-CN/Bi 2 O 3 nanostructure exhibits a 97.6 % benzylamine conversion and 99.4 % imine selectivity within 4 h under simulated solar light irradiation. The excellent activity of Bi 2 S 3 /S-CN/Bi 2 O 3 nanotubes can be attributed to the characteristic hollow defect band structure and efficient charge separation and transfer achieved by the dual Z-scheme charge transfer mechanism, which was systematically studied using electron spin resonance spectroscopy, Kelvin probe force microscope, and other techniques. The optimized dual Z-scheme heterojunction hybrid photocatalyst maintains the high oxidizing ability of Bi 2 S 3 and Bi 2 O 3 and the excellent reducing ability of CN, thereby significantly enhancing the photocatalytic activity. This research provides a facile and feasible synthesis strategy for designing dual Z-scheme heterojunctions with defect band structure to improve the photocatalytic activity. [ABSTRACT FROM AUTHOR]

This study introduces a green synthesis approach for producing tin dioxide (SnO2) nanoparticles (NPs) using Kombucha tea and evaluates their photocatalytic effectiveness in degrading the Procion Red MX‐5B (PR) dye. Characterization techniques, including UV–vis, FTIR, XRD, and TEM, confirmed the successful synthesis of SnO2 NPs with appropriate optical and structural properties. For instance; the absorption peak at 526 cm−1 in FT‐IR diagram is attributed to Sn–O which indicates the successful synthesis of SnO2. Photocatalytic tests under optimized conditions showed a notable degradation efficiency of PR dye, with the highest observed degradation efficiency reaching 97.60% at a catalyst loading of 30 mg, pH 6, in 90 min. A kinetic study was performed and the PR degradation followed first‐order reaction kinetics. For this process, the reaction kinetic rate constants were found to be 0.0589, 0.078, 0.1367, and 0.1389 min−1 for 25, 35, 45, and 55 °C, respectively. Moreover, the activation energy for the degradation process was calculated to be 25.75 kJ/mol, indicating a chemisorption mechanism. The reusability of SnO2 NPs was tested and after five subsequent usages, it still showed high degradation efficiency (95.7%). These results demonstrate the potential of Kombucha‐derived SnO2 nanoparticles as an efficient, low‐cost, reusable, and environmentally friendly photocatalyst for wastewater treatment applications. [ABSTRACT FROM AUTHOR]

Introduction: Volatile organic compounds (VOCs) have attracted widespread attention due to their adverse effects on human health. Photocatalytic oxidation is an effective technology for degrading VOCs under ambient conditions. Methods: In order to better understand the trends and development of global trends in photocatalytic oxidation of VOCs, the analysis of 2493 articles or reviews from the Science Citation Index Expanded (SCIE) in the Web of Science Core Collection, covering the period from 1998 to 2023, was conducted using CiteSpace and VOSviewer software. Results and Discussion: The findings indicate significant growth in papers concerning photocatalytic oxidation of VOCs. China emerges as the most active country among the main drivers. Principal sources publishing relevant research are Applied Catalysis B-Environmental, Chemical Engineering Journal, Journal of Hazardous Materials, and Environmental Science and Technology. A relatively well-established theoretical framework has been developed for the study of photocatalytic oxidation of VOCs. In the field of VOCs photocatalytic oxidation, the focus is on the development and optimization of advanced photocatalysts with efficient charge separation, better adsorption performance, and a wider light response range. In addition, the in-depth study of the charge generation and transfer mechanisms within the photocatalysts, as well as the comprehensive understanding of the reaction kinetics and catalytic oxidation process, the optimization of the reaction conditions, and the improvement of the catalytic efficiency are at the forefront of the research in this field. This research system is advancing and becoming more refined, with its theoretical propositions, research findings, and methodologies increasingly employed and confirmed. [ABSTRACT FROM AUTHOR]

Perylene diimides (PDIs) have garnered considerable attention due to their immense potential in photocatalysis. However, manipulating the molecular packing within their aggregates and enhancing the efficiency of photogenerated carrier recombination remain significant challenges. In this study, we demonstrate the incorporation of a PDI unit into a covalent organic framework (COF), named PDI‐PDA, by linking an ortho‐substituted PDI with p‐phenylenediamine (PDA) to control its intermolecular aggregation. The incorporation enables precise modulation of electron‐transfer dynamics, leading to a ten‐fold increase in the efficiency of photocatalytic oxidation of thioether to sulfoxide with PDI‐PDA compared to the PDI molecular counterpart, with yields exceeding 90 %. Electron property studies and density functional theory calculations show that the PDI‐PDA with its well‐defined crystal structure, enhances π–π stacking and lowers the electron transition barrier. Moreover, the strong electron‐withdrawing ability of the PDI unit promotes the spatial separation of the valency band maximum and conduction band minimum of PDI‐PDA, suppressing the rapid recombination of photogenerated electron‐hole pairs and improving the charge‐separation efficiency to give high photocatalytic efficiency. This study provides a brief but effective way for improving the photocatalytic efficiency of commonly used PDI‐based dyes by integrating them into a framework skeleton. [ABSTRACT FROM AUTHOR]

Conjugated polymers are promising photoactive materials for heterogeneous photocatalysis, but their limited solubility hinders the scalability in practical use. Herein, we develop polymer composites using processable conjugated polyelectrolytes and ionomers to fabricate photocatalytic thin films with visible light activity. The composite of conjugated polyelectrolytes and ionomers with identical counter anions in their side chains enables compatibility in solvents and stabilized charged states within the composite. This facilitates the development of stable coatings on diverse substrates and enhances charge separation and transport. The resulting photocatalytic thin films exhibited a 1.5‐fold increase in photocurrent response and a 7.0‐fold increase in mechanical strength compared to the pristine conjugated polymer. Photoactive coatings with polymer composites showcase the potential for synergistic photocatalytic oxidation of NADH, organic dye, and sulfide under visible light irradiation. The photocatalytic thin films are stable, versatile, and scalable for various photocatalytic reactions, showing promise for developing upscaled photoreactors. [ABSTRACT FROM AUTHOR]

Photocatalysis has shown power in the valorization of biomass while controlling the selectivity is a long‐standing goal and challenge, especially for the complex and reactive bio‐polyols. The selectivity control of photocatalytic biopolyols reforming to formic acid (FA) or CO is realized via engineering the electrostatic field on TiO2 semiconductor. The electrostatic field is generated by surface modification with anion adsorbates, which can alter the trap states of photoexcited holes and regulate interfacial hole transfer to the surface‐bound species, thereby strongly affecting photocatalytic activity. Taking formic acid dehydration as an example, a shallow trap of photoexcited holes on pristine TiO2 favors the dehydration of FA to CO, while a deep trap of photoexcited holes after introduced anion adsorbates makes FA stable. Based on this result, the selectivity is successfully tuned in the photocatalytic oxidation of biopolyols via controlling electrostatic field. A wide range of biopolyols can be selectively converted into FA or CO. This work presents an effective strategy to manipulate reaction pathways via generating electric field. [ABSTRACT FROM AUTHOR]

Breaking the trade‐off between broad spectrum response and efficient charge separation is a major challenge in the photocatalysis. Unlike the conventional practice of suppressing charge separation when shrinking the bandgap, a series of deacetylated chitin‐perylene diimide (DC‐PDI) donor–acceptor (D–A) photocatalysts is proposed with tunable charge distribution by modulating the C─N covalent bond content, expanding the spectral absorption range as the expanded D–A. The enlarged D–A structure achieves efficient photogenerated electron–hole separation by increasing the charge of the positive and negative charge centers, inducing larger dipole moments, generating 4.7 times higher built‐in electric field, and reducing the charge transfer barrier. Among them, the optimum DC/PDI (2:1) with enlarged D–A enables to capture the largest number of electrons for persulfate activation, and concurrently affords the highest hole generation efficiency with the deepest valence band (1.67 V). Such merits contribute to 1.2–2.8 times higher degradation rate and 1.1–1.6 times higher mineralization rate of organic pollutants in comparison with other counterparts. The mineralization rate can reach 100% in the engineered microreactor setup. This study elucidates the structure‐mechanism‐performance relationship of D–A modulation and charge separation/transport, guiding the rational molecular structure design for efficient photocatalytic oxidation. [ABSTRACT FROM AUTHOR]

We report the photocatalytic oxidation of α‐carbonyl radicals of amides or esters to the corresponding α‐carbonyl carbocations through super photoreductant CBZ6 induced redox‐neutral photocatalysis. The α‐carbonyl radicals are formed by the β‐addition of alkyl radicals generated in situ by the photocatalytic fragmentation of N‐hydroxyphthalimide esters to the α,β‐unsaturated amides and esters. This method enables the α‐nucleophilic addition of hydroxyl or alkoxyl radicals to amides and esters without any prefunctionalization. [ABSTRACT FROM AUTHOR]

Oxygen vacancy (Ov) sites play a critical role in the activation and deep oxidation of nitric oxide (NO). However, controlling the concentration and type of Ov remains a significant challenge. In this study, Bi2W(Mo)O6‐x is investigated as a model system and demonstrates that increasing the concentration of Ov substantially enhances the efficiency of air NO removal. Increasing the Ov concentrations in Bi2WO6‐x and Bi2MoO6‐x improves NO removal efficiency ≈12‐ and 11‐fold, respectively, compared to their low‐Ov counterparts. This enhancement is attributed to improved adsorption and activation of NO/O2 molecules, better separation and transfer of photogenerated carriers, and increased visible light absorption. Notably, Bi2WO6‐x remains highly stable over ten recycling tests for continuous air NO deep photooxidation, while Bi2MoO6‐x shows a 43.5% decrease in efficiency after ten runs. This sustained performance is attributed to stable Ovs without changes in metal ion valence, unlike Bi2MoO6‐x, where instability arises from the reduction of Mo6+ to Mo4+. In situ DRIFTS reveals possible pathways for the deep photooxidation of NO to nitrate (NO3−). This study provides valuable insights into designing high‐performance, durable catalysts by effectively controlling Ov concentration and type, paving the way for efficient photocatalytic air purification technologies. [ABSTRACT FROM AUTHOR]

This study explores the use of biochar, derived from Borassus flabellifer male inflorescence biomass as an alternative support for titanium dioxide (TiO2) to enhance its photocatalytic activity in degrading Congo red (CR) dye pollutant. The biochar was synthesized through controlled pyrolysis and subsequently combined with TiO2 to form a nanocomposite via hydrothermal method. The primary goal of creating this nanocomposite is to breakdown azo dyes, such as CR, using UV irradiation. Comprehensive characterization techniques, including XRD, FTIR, SEM coupled with EDAX, XPS, and UV‐DRS confirmed the successful integration of biochar with TiO2. The enhanced photocatalyst performance is attributed to the increased surface area, improved light absorption, and efficient charge separation facilitated by the biochar support. Furthermore, the experimental parameters were optimized using the response surface methodology (RSM). These studies demonstrated that the CR concentration, contact duration, pH, and photocatalyst quantity are critical factors in the photocatalytic oxidation process. The strong correlation coefficient for the first order model indicated that the data described by the RSM, agreed with the obtained results. This study highlights the potential of agricultural waste‐derived biochar as a cost‐effective and sustainable support for TiO₂, offering a viable solution for the remediation of dye‐contaminated water. [ABSTRACT FROM AUTHOR]

The availability of fresh water is limited compared to its huge consumption. Conversely, certain industries like dyes, textiles, paper, and tanning not only consume vast quantities of fresh water, but also generate significant amounts of wastewater that poses severe threats to living organisms. The present investigation focuses on the degradation of Rhodamine-B (Rh–B) as a model pollutant by using the nanocomposite based on waste scrap tire-derived activated carbon (AC) and titanium dioxide (TiO 2). These nanostructures were fabricated using wet chemistry techniques. Analysis using scanning electron microscopy (SEM) revealed that the morphology of the structures remained largely unchanged even with a concentration of 6 mg of AC. X-ray diffraction (XRD) results confirmed the successful fabrication of rutile and anatase phases of TiO 2 @AC nanocomposite. The XPS results confirmed the presence of AC and TiO 2 in the composite. Furthermore, the optical band gap of the nanocomposites decreased up to 17.17 % and 34.57 % through direct and indirect methods respectively, owing to the varying quantity of AC used. The narrowing of optical band gap and the increased surface oxygen vacancies were caused by the successive addition of AC during the synthesis of nanocomposites. This resulted in the efficient degradation of Rhodamine-B (Rh–B) using adsorption and photocatalytic oxidation. The findings demonstrate a significant influence of AC on the TiO 2 catalyst in the removal of Rh–B dye. The maximum efficiency of dye removal, reaching up to 99.14 %, was achieved with the highest concentration of AC, thus demonstrating almost complete elimination of Rh–B dye. The findings suggest that the use of waste scrap tires can be effectively applied to design efficient photocatalysts for addressing the wastewater management issues. [ABSTRACT FROM AUTHOR]

In this work, for the first time, the photocatalytic oxidative desulfurizing of thiophene through exposure to visible light was performed on mesoporous MnCo 2 O 4 /YVO 4 heterojunctions. Mesoporous YVO 4 nanocrystals were combined with MnCo 2 O 4 nanoparticles (NPs) to construct MnCo 2 O 4 /YVO 4 heterostructure candidates using an easy sol-gel approach. The constructed mesoporous YVO 4 with a tetragonal structure has a large surface area of approximately 200.0 m2 g−1. Within 90-min visible light exposure, the 9.0 wt% MnCo 2 O 4 /YVO 4 nanocomposite photocatalyst exhibited 100.0 % desulfurization efficacy, which was ∼25.0 folds greater than occurred using the unmodified YVO 4 (only 4.0 %). Notably, the 9.0 wt% MnCo 2 O 4 /YVO 4 photocatalyst displayed a desulfurization rate of ca. 269.19 μmol L−1 min−1, which was ∼55.00 folds higher than that occurred on the unmodified YVO 4 material (4.90 μmol L−1 min−1). The constructed MnCo 2 O 4 /YVO 4 heterostructure exhibited preeminently superb photocatalytic thiophene oxidation with superior recyclability than nonmodified YVO 4. The n-n heterojunction construction between MnCo 2 O 4 and YVO 4 played a major role in synergistic promoting the photocatalytic efficacy of the MnCo 2 O 4 /YVO 4 nanocomposite through enlarging the photoabsorbance capability and promoting photoexcited carriers' separation. Moreover, the abundant surface reactive sites originating from the mesoporous nature of the constructed heterostructure candidates significantly contributed to enhancing the photocatalytic thiophene oxidation. The 9.0 wt% MnCo 2 O 4 /YVO 4 candidate exhibited high stability within 600.0 min. Overall, this contribution not only presents a new MnCo 2 O 4 /YVO 4 heterojunction, fabricated by an easy approach for highly efficient desulfurizing of thiophene but also provides good ideas for establishing other heterostructure materials. [Display omitted] [ABSTRACT FROM AUTHOR]

The present review is related to the novel approach for improvement of the optical properties of wide bandgap metal oxides, in particular TiO2, based on the formation of the inorganic–organic hybrids that display absorption in the visible spectral range due to the formation of interfacial charge transfer (ICT) complexes. We outlined the property requirements of TiO2-based ICT complexes for efficient photo-induced catalytic reactions, emphasizing the simplicity of the synthetic procedure, the possibility of the fine-tuning of the optical properties supported by the density functional theory (DFT) calculations, and the formation of a covalent linkage between the inorganic and organic components of hybrids, i.e., the nature of the interface. In addition, this study provides a comprehensive insight into the potential applications of TiO2-based ICT complexes in photo-driven catalytic reactions (water splitting and degradation of organic molecules), including the identification of the reactive species that participate in photocatalytic reactions by the spin-trapping electron paramagnetic resonance (EPR) technique. Considering the practically limitless number of combinations between the inorganic and organic components capable of forming oxide-based ICT complexes and with the knowledge that this research area is unexplored, we are confident it is worth studying, and we emphasized some further perspectives. [ABSTRACT FROM AUTHOR]

Indoor air quality (IAQ) has emerged as a global concern due to the increasing presence of indoor pollutants, which have been shown to negatively impact public health. These pollutants stem from various household activities and the materials used in buildings. Previous studies have explored several methods to improve IAQ, including gas adsorption, ozonation, non-thermal plasma, and photocatalytic oxidation (PCO). However, these methods often have drawbacks, such as generating secondary pollutants or incurring high costs. This study examines the effectiveness of photocatalytic paint, which is activated by visible light, in controlling fungal growth to enhance IAQ. Experimental results showed that when applied to grown fungi, the photocatalytic paint led to a significant reduction in the size of fungal fibers, as observed through scanning electron microscopy (SEM). Furthermore, exposure to the photocatalytic paint reduced the size of fungal hyphae by 37% after 85 h. The paint produced by adding 1 mL photocatalytic paint to 10 mL commercial paint demonstrated high efficiency in fungi removal, i.e., reducing the weight of fungi by approximately 45% within 3 h. These results highlight the potential of photocatalytic paint to significantly inhibit fungal growth, offering a promising solution for improving indoor environments. [ABSTRACT FROM AUTHOR]

The current investigation deals with improving the synthesis of cobalt‐doped titanium dioxide (TiO2) utilizing both ultrasound‐assisted and conventional impregnation methods with an objective to obtain better catalyst characteristics. The impacts of process parameters such as sonication power, irradiation time, duty cycle and precursor doping on the catalyst characteristics have been analysed to optimize the catalyst characteristics including its particle size. Different characterization methods, including XRD, BET, TEM and FTIR have been used to compare the catalysts produced using both approaches under optimal conditions. Catalyst synthesized at 1 mol% doping, 90 min as irradiation time, 80 W as sonication power and 50% as duty cycle showed a minimum particle size of 231 nm and surface area of 9.2 m2/g. The catalyst obtained utilizing the ultrasound‐assisted technique was obtained in significantly lesser time (90 min) compared to the catalyst obtained using the conventional approach (24 h). Photocatalytic oxidation tests carried out to determine the activity also showed that the Co‐doped TiO2 catalyst obtained ultrasonically showed maximum activity for degradation of Acid Violet 7 in conjunction with H2O2 at the optimal loading. [ABSTRACT FROM AUTHOR]

Cadmium sulfide quantum dots (CdS QDs) photocatalysts were prepared by the hydrothermal method, and 5-hydroxymethylfurfural (HMF) was catalyzed to 2,5-diformylfuran (DFF) under light irradiation, with fewer by-products and a selectivity of 95.74%. In the process of photocatalytic oxidation of HMF, the selectivity of DFF was higher when acetonitrile was used as the reaction solvent, which was more conducive to the production of DFF. Meanwhile, the conversion rate of HMF improved with the increase in reaction time. However, the selectivity of DFF decreased when the reaction time exceeded 10 h. Under the optimal reaction conditions, the conversion of HMF, the yield and the selectivity of 2,5-diformylfuran showed the best photocatalytic effect, which were 42.57, 40.64, and 95.47%, respectively. It was found out that superoxide radical was the main active species involved in the photocatalytic reaction, while the photogenic hole was the secondary active species. Further, the mechanism of the photocatalytic reaction was deduced. [ABSTRACT FROM AUTHOR]

Calcium hydroxyapatite (HAp) is a naturally occurring material in bones of humans and calcareous animals. In the biomedical field, HAp has been extensively used due to their high biocompatibility and non-toxicity. These properties of HAp coupled with high surface area and adsorption capacity have prompted its application in wastewater remediation. The most notable environmental application of HAp has been as an adsorbent and as base matrix for supporting photocatalysts. Interestingly, recent investigations have revealed the inherent photocatalytic properties of HAp, deeming it as a promising green photocatalytic material. Further, the photocatalytic behaviour of single-phase HAp can be accentuated by doping transition metals. A defect is created when metal dopant substitutes the Ca+2 ions in the HAp lattice, which makes the HAp/metal composite responsive to sustainable solar energy. This review stresses the different applications of HAps in wastewater remediation with impetus on the photocatalytic advanced oxidation process. In addition, a photocatalytic degradation pathway and a novel kinetic model of the HAp-based photocatalytic oxidation process have been proposed to understand the degradation mechanism and kinetics of pollutant removal. Furthermore, the recent investigations of HAp-based ceramic membranes have been elaborated in current work to demonstrate its remarkable hydrophilic and antibiofouling properties desirable in wastewater treatment with membrane filtration and photocatalytic membrane process. However, substantial improvements are required before upscaled HAp-based wastewater treatment technologies can be materialised. The future prospects for the upscaling and limitation of the HAp-based technology have been extensively discussed to lay the path for forthcoming investigations. [ABSTRACT FROM AUTHOR]

Ethylene management and manipulating storage conditions are crucial elements that impact the postharvest quality of apple fruit. This study demonstrated the optimal approach for preserving the quality of 'Cripps Pink' apple fruit during storage by minimizing ethylene production and action, respiration rate, physiological loss of weight (PLW), and textural changes. Ethylene antagonist treatment had the greatest impact on suppressing ethylene and respiration peaks, while storage duration notably influenced fruit firmness and PLW. Fumigation treatment with 1-methylcyclopropene (MCP), 1H-cyclopropabenzene (BC), and 1H-cyclopropa[b]naphthalene (NC) effectively reduced ethylene and respiration peaks. Storage conditions (cold, controlled atmosphere, and photocatalytic oxidation) affected ethylene production and respiration, with ozonized storage showing higher rates. Prolonged storage led to increased PLW, ethylene production, and decreased fruit firmness. The most effective treatment combination for ethylene action antagonism and maintaining fruit quality was MCP treatment in ozonized cold storage for 120 d. [ABSTRACT FROM AUTHOR]

Herein, the first photochemical microscale continuous oscillatory baffled reactor, that is, Photo‐μCOBR, was designed and evaluated. Computational fluid dynamics simulations were used to optimize the key structural parameter and operating conditions. Then, the mixing process was simulated and the μCOBR was shown to be more than 23 times faster than the straight channel both under oscillating conditions. Finally, a glass Photo‐μCOBR was fabricated by femtosecond laser internal engraving technology, and the photocatalytic gas–liquid oxidation of dihydroartemisinic acid was performed. A yield of 65.9% was achieved in a residence time of ~120 s and at a gas–liquid flow rate ratio of 1:3 (vs. 18.6% in the capillary photomicroreactor under identical conditions). The results in this work offer guidelines for the design and operation of microscale COBRs, and the as‐fabricated Photo‐μCOBR displays good potential for gas–liquid photochemical reactions. [ABSTRACT FROM AUTHOR]

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Bismuth‐based photocatalysts have been widely employed in the photocatalytic degradation of organic pollutants in wastewater. However, the lack of rational structural design and the slow generation of active free radicals have hindered its efficiency. Here, we stabilized Bi2WO6 nanoparticles by wrapping them with hydroxyl groups, introduced metal Cu doping, and underwent an annealing process to construct Cu‐BiNP nanocatalysts with exposed active sites. Under visible light irradiation, 0.03Cu‐BiNP achieved a 94.5% TC degradation efficiency, which is 15.8 times higher than the rate of bulk BiWO. The 0D structure endows Cu‐BiNP with ample opportunities for O2 adsorption and activation, and Cu atomic doping reduces the bandgap and increases the oxygen vacancy, promoting the generation of active oxygen species. This work demonstrates the rapid charge separation and activation of O2 to generate active oxygen species by 0D bismuth‐based nanocatalysts in photocatalytic oxidation reactions, providing a scalable nanocatalyst platform for TC photocatalytic degradation. [ABSTRACT FROM AUTHOR]

Even distribution of core–shell heterojunction on porous catalyst supports is promising to get the super‐catalysts, yet laborious preparation hinders the wide application. A novel strategy of urea enzymolysis‐induced ions replacement is proposed for one‐pot loading of Bi12O17Cl2@Bi48Al2O75 core–shell heterojunction onto porous Al2O3 nanorod (named as Al2O3‐Bi12O17Cl2@Bi48Al2O75). The clever combination of urea enzymolysis and precipitation reactions that consume the ions generated in urea enzymolysis can switch the “on‐off” of urease, and thus allow the precise controlling of the concentration and existence time of the ions, as well as ions replacement. It is the urea enzymolysis‐induced ions replacing strategy that can generate the unique structure of Al2O3‐Bi12O17Cl2@Bi48Al2O75, and it is the distinctive structure that can get the selectivity of 96% benzaldehyde with 90% benzyl alcohol (BA) conversion in the photocatalytic oxidation of BA. The ions replacement, the growth of Al2O3‐Bi12O17Cl2@Bi48Al2O75, and the photocatalytic mechanism are investigated in detail. This work highlights a novel and convenient strategy for one‐pot loading core–shell heterojunction onto porous nanorod support, unveils a fresh biosynthesis of nanomaterials with elaborate structure, and thus paves the way for wide application of elaborate nanomaterials. [ABSTRACT FROM AUTHOR]

Anchoring groups play an important role in the assembly of functional molecules onto semiconductor substrates for dye‐sensitized photocatalysis. In addition to directly influencing the adsorption stability, anchoring groups significantly impact the efficiency of electron or hole injection into the substrate, which is a crucial step for photocatalytic reactions. Most reported dye‐sensitized photocatalytic systems, including semiconductor nanoparticles and photoelectrochemical cells, are prepared using the carboxylic or phosphonic acid anchors. The systems prepared with these conventional anchors usually suffer from low adsorption stability in aqueous media. Alternatively, pyridine has emerged as an anchoring group of photosensitizers and molecular catalysts in the construction of photocatalytic systems. The resulting semiconductor nanoparticles and photoelectrodes show superior adsorption stability in aqueous media, providing a simple and efficient way to sensitize the metal or metal oxide substrate. This review focuses on the recent advances of such a pyridine anchoring strategy in the assembly of photosensitizers and molecular catalysts for photocatalytic applications, mainly including photocatalytic water oxidation, reduction, and splitting. The further exploration and understanding of the pyridine‐anchoring method are believed to boost the development of advanced dye‐sensitized photocatalytic devices and technologies. [ABSTRACT FROM AUTHOR]

The synthesis of sulfoxides has long attracted considerable interest due to their pivotal role in organic synthesis, pharmaceutics and environmental protection. Oxidation of the corresponding sulfides is recognized as the most effective strategy. Traditional oxidation methods, however, fall short of the growing demands of green chemistry. Photocatalytic aerobic oxidation has thus garnered attention, employing the greenest and most sustainable oxidants—oxygen or air—and sunlight as the energy source. Nevertheless, these reactions are typically conducted in potentially pollutive organic solvents rather than in the greenest solvent, water. To facilitate this organic transformation in aqueous phase, molecular reactors that can encapsulate reactants within their confined pores and facilitate photocatalytic reactions have been developed recently. This Concept article summarizes the development of molecular reactors for the photocatalytic oxidation of sulfides and provides perspectives for the design and construction of effective photocatalytic molecular reactors. [ABSTRACT FROM AUTHOR]

The efficient separation of photocarriers and facile generation of superoxide radicals are crucial for enhancing the performance of photocatalysts in the selectively photo‐oxidizing 5‐hydroxymethylfurfural (HMF) into 2,5‐diformylfuran (DFF). Herein, a ZnIn2S4/CeO2 composite with S‐scheme heterojunction and sulfur vacancies (SV) is successfully developed through a one‐step hydrothermal method. The optimal catalyst (SV‐ZnIn2S4/CeO2) exhibits excellent catalytic activity with 100% conversion of HMF and 96.1% selectivity of DFF in 80 min under ambient conditions, the production rate of DFF is up to 952.6 µmol g−1 h−1. Intriguingly, the performance remains significant even when the concentration of HMF is increased from 8 to 100 mм. Experimental and theoretical investigations discover that the synergistic effect of S‐scheme heterojunction and sulfur vacancies contribute to the separation of photocarriers and the activation of oxygen, which facilitate the generation of superoxide radicals, thus boosting the catalytic oxidation reactions. [ABSTRACT FROM AUTHOR]

This study introduces a novel solution to the design of structured catalysts, integrating single‐piece 3D printing with single‐atom catalysis. Structured catalysts are widely employed in industrial processes, as they provide optimal mass and heat transfer, leading to a more efficient use of catalytic materials. They are conventionally prepared using ceramic or metallic bodies, which are then washcoated and impregnated with catalytically active layers. However, this approach may lead to adhesion issues of the latter. By employing photopolymerization printing, a stable and active single‐atom catalyst is directly shaped into a stand‐alone, single‐piece structured material. The battery of characterization methods employed in the present study confirms the uniform distribution of catalytically active species and the structural integrity of the material. Computational fluid dynamics simulations are applied to demonstrate enhanced momentum transfer and light distribution within the structured body. The materials are finally evaluated in the continuous‐flow photocatalytic oxidation of benzyl alcohol to benzaldehyde, a relevant reaction to prepare biomass‐derived building blocks. The innovative approach reported herein to manufacture a structured single‐atom catalyst circumvents the complexities of traditional synthetic methods, offering scalability and efficiency improvements, and highlights the transformative role of 3D printing in catalysis engineering to revolutionize catalysts' design. [ABSTRACT FROM AUTHOR]

In this study, ultra-small nickel nanoparticles on NiFe 2 O 4 (Ni@NiFe 2 O 4) and Ni@NiFe 2 O 4 /ZnO magnetic nanocomposites were synthesized and utilized for the solar light-driven photocatalytic degradation of cefadroxil. The drug cefadroxil is widely used to treat bacterial infections and cefadroxil is a non-biodegradable pharmaceutical compound detected in the groundwater sources because of its low removal efficiency. The Raman active phonon at 540 cm−1 confirms the presence of Ni nanoparticles at the surface of NiFe 2 O 4 /ZnO. DR-UV-Vis analysis exhibited surface plasmon resonance at 350 nm for ultra-small nickel nanoparticles. The observed optical bandgap values for Ni@NiFe 2 O 4 and NiFe 2 O 4 /ZnO are 1.2 eV and 2.43 eV, respectively. Which indicates that these magnetic nanocomposites can be utilized for the mineralization of cefadroxil (β-lactam antibiotic) under ambient environmental conditions. The efficiency was determined by the direct solar light driven photocatalytic oxidation of cefadroxil in the presence and absence of peroxymonosulphate (PMS). The experimental findings exhibits that ∼95 % of cefadroxil (CDL) was eliminated by the ultra-small Ni@NiFe 2 O 4 /ZnO within 60 min (k = 7.5 × 10−4 s−1) of direct solar light irradiation. Further, the addition of PMS enhanced the photodegradation to achieve 100 % cefadroxil oxidation within 40 min (k = 25 × 10−4 s−1) of direct sunlight. The efficiency of the nanocatalyst was compared with controlled experiments and was found to be Fe 2 O 3 < ZnO < TiO 2 (P25) < Ni@NiFe 2 O 4 < Ni@NiFe 2 O 4 /ZnO under absence and presence of PMS. Moreover, ultra-small Ni@NiFe 2 O 4 /ZnO nanophotocatalyst were stable up to 3 consecutive cycles. [ABSTRACT FROM AUTHOR]

Acetic acid (AA), a vital compound in chemical production and materials manufacturing, is conventionally synthesized by starting with coal or methane through multiple steps including high‐temperature transformations. Here we present a new synthesis of AA from ethane through photocatalytic selective oxidation of ethane by H2O2 at 0–25 °C. The catalyst designed for this process comprises g‐C3N4 with anchored Pd1 single‐atom sites. In situ studies and computational simulation suggest the immobilized Pd1 atom becomes positively charged under photocatalytic condition. Under photoirradiation, the holes on the Pd1 single‐atom of OH−Pd1⊕ ${{}^{\oplus }}$ /g‐C3N4 serves as a catalytic site for activating a C−H instead of C−C of C2H6 with a low activation barrier of 0.14 eV, through a concerted mechanism. Remarkably, the selectivity for synthesizing AA reaches 98.7 %, achieved under atmospheric pressure of ethane at 0 °C. By integrating photocatalysis with thermal catalysis, we introduce a highly selective, environmentally friendly, energy‐efficient synthetic route for AA, starting from ethane, presenting a promising alternative for AA synthesis. This integration of photocatalysis in low‐temperature oxidation demonstrates a new route of selective oxidation of light alkanes. [ABSTRACT FROM AUTHOR]

Carbon nitrides have emerged as promising supports for catalytically active metals in various chemical reactions. Among these, the selective oxidation of benzene to phenol stands out as particularly challenging within the chemical industry due to its traditionally low yields and complex reaction pathways. In our current investigation, we have focused on the synthesis of ionic carbon nitride fragments via a straightforward alkaline hydrolysis method. These fragments demonstrate a remarkable ability to stabilize iron cations within the carbon nitride structure (Frag‐Fe), resulting in a highly efficient photocatalyst for benzene oxidation. Employing hydrogen peroxide as the oxidant in a single‐step reaction, we achieved an impressive 47 % yield of phenol using Frag‐Fe at 12 hours, with negligible production of CO2 as a byproduct. This compelling outcome underscores the effectiveness of our alkaline synthesis approach in generating carbon nitride‐based photocatalysts with exceptional activity for C−H oxidation reactions. Our findings not only contribute to the advancement of carbon nitride‐based catalysis, but also hold significant promise for the development of more sustainable and efficient chemical processes in the future. [ABSTRACT FROM AUTHOR]

Photocatalytic CH4 oxidation to CH3OH emerges as a promising strategy to sustainably utilize natural gas and mitigate the greenhouse effect. However, there remains a significant challenge for the synthesis of methanol by using O2 at low temperature. Inspired by the catalytic structure in soluble methane monooxygenase (MMO) and the corresponding reaction mechanism, we prepared a biomimetic photocatalyst with the decoration of Fe2O3 nanoclusters and satellite Fe single atoms immobilized on carbon nitride. The catalyst demonstrates an excellent CH3OH productivity of 5.02 mmol ⋅ gcat−1 ⋅ h−1 with CH3OH selectivity of 98.5 %. Mechanism studies reveal that the synergy between Fe2O3 nanoclusters and Fe single atoms establishes a dual‐Fe site as MMO for O2 activation and subsequent CH4 partial oxidation. Moreover, the light excitation of Fe2O3 nanoclusters with a relative narrow band gap could deliver the electrons and protons to atomic Fe that facilitating the oxygen reduction kinetics for the robust of CH3OH synthesis. [ABSTRACT FROM AUTHOR]

A heterogeneous photocatalyst was assembled through electrostatic immobilization of a cationic porphyrin at the surface of functionalized carbon nanotubes. The supra‐molecular nanohybrid catalyst was valorized in the aerobic photo‐oxidation of sulfides to the corresponding sulfoxides. The process operated selectively under visible light, with low catalytic loading, in water as the solvent, and the catalyst was readily recycled and reused. [ABSTRACT FROM AUTHOR]

The efficiency of photocatalysts depends largely on the accessibility of reaction species to the active centre, the electron transfer and geometric matching between the active surface of the catalyst and reaction species. In this work, we successfully synthesized and designed one two-dimensional Mn(II) MOF with [Mn2(H2L1)(H2O)2(DMF)2]n·(CH3CH2OH)n (HSTC 3) by using MnCl2·4H2O and 5,5′-(anthracene-9,10-diyl)diisophthalic acid (H4L1), in which the adjacent layers are stacked with weak interactions, and the huge gap leads to the interpenetration between layers to form a 2D + 2D → 3D interpenetration frame. Based on the particularity of the structure of HSTC 3, ultrasonic wall breaking methods were tried to successfully peel HSTC 3 into nanosheets (HSTC 3-NS), thus achieving a significant improvement in a series of optoelectronic properties due to exposure to more active centres for HSTC 3-NS. These results significantly enhance the photocatalytic selective oxidation of thioether. This study provides a new insight into the post-synthesis modification of MOF photocatalyst and their application in photocatalytic organic synthesis. [ABSTRACT FROM AUTHOR]

Direct photocatalytic conversion of benzene to phenol with molecular oxygen (O2) is a green alternative to the traditional synthesis. The key is to find an effective photocatalyst to do the trick. Defect engineering of semiconductors with oxygen vacancies (OVs) is an emerging strategy for catalyst fabrication. OVs can trap electrons to promote charge separation and serving as adsorption sites for O2 activation. However, the randomly distribution of OVs on the semiconductor surface often results in mismatching the charge carrier dynamics under irradiation, thus failing to fulfill the unique advantages of OVs for photoredox functions. Herein, we demonstrate that abundant OVs can be facilely generated and precisely located adjacent to the reductive sites on reducible oxide semiconductors such as tungsten oxide (WO3) via a simple photochemistry strategy. Such photoinduced OVs are well suited for photocatalytic benzene oxidation with O2 as they readily capture photogenerated electrons from the reductive sites of WO3 to activate adsorbed O2. The oxygen‐isotope‐labeling experiments further confirm that the OVs also facilitate the integration of oxygen atoms from O2 into phenol, revealing in detail the pathway for photocatalytic benzene hydroxylation. This study demonstrates that the photochemistry approach is an appealing strategy for the synthesis of high‐performance OVs‐rich photocatalysts for solar‐induced chemical conversion. [ABSTRACT FROM AUTHOR]