With the increasingly water pollution, treatment technologies for the pollutant removal, including metal ions and organics, have attracted wide attentions. Herein, we reported a coupled photocatalysis-membrane distillation reactor (PMR) based on BiOBr film for the simultaneous process of coexisted metal ion recovery (Ag+ and Au3+) and organics elimination (4-chlorophenol, 4-CP). The high efficiency of pollutant removal and water purification was successfully achieved. More importantly, Ag+ and Au3+ was photo-reduced into nanoparticles loaded on the surface of BiOBr film, and further enhanced the 4-CP photo-degradation. It could be found that Ag+ ions greatly promoted the reduction of Au3+ ions into Au nanoparticles, which further enhance the organics degradation. At the same time, Ag nanoparticles reduced from Ag+ ions effectively consumed the photo-generated electrons to simultaneously improve the photocatalytic oxidation. This PMR system provided valuable insights for simultaneously achieving the elimination of organics and recovery of heavy metal ions from wastewater.

Photocatalytic reduction of nitrate (NO3 -) to ammonia (NH3) has garnered growing attention as a sustainable route for simultaneous nitrate pollution remediation and value-added ammonia synthesis under ambient conditions. However, its efficiency remains severely limited by the intrinsically high structural stability of nitrate anions and inefficient charge-carrier utilization. In this study, a Fe-doped Bi/Bi2WO6 photocatalyst (H-Fe-B/BWO) is constructed via a facile hydrothermal method followed by calcination in a reducing atmosphere. The experimental results reveal that the optimized H-Fe-B/BWO exhibits significantly enhanced photocatalytic nitrate reduction performance, achieving an NH3 production rate of 2.419 mmol gcat -1 h-1 with a high selectivity of 99.3% in the presence of ethylene glycol (EG), representing an approximately 4.5-fold improvement compared with pristine Bi2WO6. The remarkable enhancement originates from the synergistic effect between Lewis acidic sites generated by Fe dopants with unsaturated coordination environments and the surface plasmon resonance of metallic Bi, which collectively facilitates nitrate activation and improves charge-carrier separation and utilization. This work provides a rational strategy for designing efficient photocatalysts for selective NO3 --to-NH3 conversion under environmentally benign conditions, contributing to sustainable nitrogen management and circular economy-driven resource recovery.

Micromotors with autonomous motion by multiple driving forces have attracted wide attentions. In this work, we successfully constructed MnO2-carbon microspheres (Mn-Cs) composite micromotors with synergistic photothermal-bubbly driving effect. The uniform MnO2 loading and the stable combination of MnO2 with Cs in Mn-Cs composite facilitated to improve the photothermal conversion performance. The regular morphology and large specific surface area of Mn-Cs were beneficial for the in-situ photocatalytic decomposition of H2O2 under light irradiation. Notably, the photothermal conversion effect of Mn-Cs could further promote the decomposition of H2O2. The low thermal conductivity of air was beneficial for expanding the temperature gradient between the micromotor surface and the environment. As a result, the speed of optimal 1.0-Mn-Cs sample under the light irradiation and addition of H2O2 (75.2 mu m/s) was 14.3 and 5.88 times higher than that individual light irradiation (5.27 mu m/s) and addition of H2O2 (12.8 mu m/s), respectively. It was indicative of the great significance of synergistic photothermal-bubbly driving effect. This study provided a new strategy for developing synergistically driven micromotors to reduce chemical fuel dependence, and showed a significant prospect in green, economic and sustainable applications.

ZIF-67@CoO@Co foil was successfully prepared for photoelectrocatalytic (PEC) sterilization of Escherichia coli (E. coli). E. coli can be initially anchored by ZIF-67@CoO@Co foil with initiative invasion, facilitating the PEC antibacterial activity. The visible light harvesting and charge separation is enhanced by the p-n ZIF-67@CoO heterojunction to efficiently generate & sdot;OH radicals for the destruction of cell membranes. Furthermore, ZIF-67@CoO@Co foil effectively induces the increased malondialdehyde (MDA), and degrades the enzymes of superoxide dismutase (SOD) and catalase (CAT) by the abundant mesopores. It benefits to compromise the defense and antioxidant capacity of bacteria. The leakage of K+ ions, assisted by the in-situ absorbance of human potassium channel protein (hERG) on ZIF-67@CoO@Co foil, accelerates the biological dysfunction of bacteria. This study provides valuable insights for the development of multifunctional antibacterial technologies and the understanding of sterilization mechanisms.

Facing the great challenge for efficient utilization of solar light, the design of photothermal-propelled micromotors is significant for converting optical energy into thermal energy to achieve the in situ manipulated motion. Assisted by the photothermal-propelled function, a synergistic photocatalytic-photothermal antibacterial system is successfully constructed in this work, based on the Au-CeO2 micromotor. The selective growth of CeO2 nanoparticles on the surface of Au nanorods (NRs) is achieved with the adjustable Au exposure ratio. The strong interaction of CeO2 with Au NRs realizes the enhanced visible light harvesting and the promoted photo-induced charge separation. Especially, the self-induced thermophoretic force on asymmetric lollipop-like L-Au-CeO2 with higher Au exposure ratio is more powerful than that on symmetric core-shelled CS-Au-CeO2 and dumbbell-like D-Au-CeO2. As a result, its local temperature gradient is greater and thus realizes the in situ manipulated motion with higher velocity and stronger directionality. It further facilitates the contact with bacteria and promotes the synergistic photocatalytic-photothermal antibacterial performance for the probe bacteria of Escherichia coli. This powerful photothermal-propelled Au-CeO2 micromotor shows significant potential for the microorganism control in biomedical and environmental applications.

The photocatalytic membrane systems show great potential for water purification and wastewater treatment with efficient energy utilization. Herein, we develop a synergistic photocatalytic-photothermal route, based on PdTiO 2 /PEDOT composite immobilized in PVDF membrane, for effective water permeability and reutilization property. Novel Pd-TiO 2 /PEDOT/PVDF ultrafiltration membrane is prepared by the phase inversion method with immobilizing Pd-TiO 2 /PEDOT obtained by ultrasonic irradiation. During the removal of HA under light irradiation, Pd-TiO 2 /PEDOT/PVDF membrane presents an unexpected increasing in water flux, when compared to pristine PVDF, Pd-TiO 2 /PVDF and PEDOT/PVDF membranes, with the highest normalized flux reaches up to 2.1 and remains as 1.3 even after 300 min of irradiation. This significantly enhances the water transport, along with the achieved high rejection and anti-fouling performance. It can be attributed to synergistic photocatalyticphotothermal effect of Pd-TiO 2 /PEDOT, which is realized by their strong interaction and uniform distribution. The addition of PEDOT promotes photocatalytic effect of Pd-TiO 2 by enhancing separation of photo-induced charges. High photothermal conversion efficiency of Pd-TiO 2 /PEDOT and low temperature difference in PdTiO 2 /PEDOT/PVDF membrane facilitate effective thermal storage, beneficial for water transport. Meanwhile, thermal energy promotes generation of more center dot OH and center dot O 2 - radicals to remove pollutants. Synergistic photocatalytic-photothermal contribution in Pd-TiO 2 /PEDOT/PVDF membrane shows significant potential for practical application.

As a feasible strategy to solve worldwide energy problems, solar energy attracts much attention due to its merits of low cost, stability and no space limit. Photocatalysis attracts wide attention since it is considered as one of the promising ways to utilize solar energy. However, the limitations of photocatalysis prohibit its further practical applications. The synergistic photocatalytic-photothermal route can realize more effective utilization of solar light. It can not only overcome restrictions of photocatalysis but also produce required localized heat for reaction from UV-visible light to near infrared light. Thus, photocatalytic-photothermal effects are widely used in various fields. Achieving a high solar-to-heat conversion rate plays an essential role in the fields of hydrogen generation, carbon dioxide reduction, antimicrobial and membrane separation. Especially, sterilization can effectively exhibit its own superiority and inhibit the limitation of photocatalysis. The temperature can increase until reaching the denaturation temperature of bacteria by local heat effect induced by the photothermal effect. In addition, the photocatalytic-photothermal effect in membrane separation could be beneficial by generating more radicals. Meanwhile, temperature induced by photon energy could improve water evaporation and water permeation performance. Our previous studies on antibacterial and wastewater treatment by the photothermal-photocatalytic effect are introduced. We proposed that high photothermal conversion efficiency and efficient generation of photo-induced holes and electrons were beneficial for forming more ROS species. These active species were powerful for oxidizing bacteria leading to their death, completely mineralizing organic pollutants or recovering heavy metals. According to proposed photothermal-photocatalytic mechanisms, new perspectives and insights are provided for the wide utilization of the photocatalytic-photothermal effect in the future. The synergistic photocatalytic-photothermal effect realizes more effective utilization of solar energy, which can be used in the fields of hydrogen generation, carbon dioxide reduction, sterilization and membrane separation.

The photocatalytic CC coupling of benzyl alcohol (BA) into hydrobenzoin (HB), is appealing to obtain high-value chemicals. However, the selectivity of HB is still low due to the inevitable formation of benzaldehyde. Herein, we report In(OH)(3)-ZnS photocatalyst for CC coupling of BA into HB with very high selectivity (similar to 100 %). The introduction of In(OH)(3) onto ZnS with stable interaction facilitates light harvesting and separation of photo-excited charges. As a result, BA conversion on optimized In(0.1)-ZnS catalyst (73 %) is much higher than ZnS (29 %). Besides, the surface hydroxyl groups derived from In(OH)(3) enables the facile desorption of CH(OH)Ph radical. Therefore, the over oxidation of CH(OH)Ph radical into by-product of benzaldehyde can be effectively inhibited. More significantly, in-situ FTIR spectra and reduction of by-product manifest the instant reverse reduction process of benzaldehyde into CH(OH)Ph radical during CC coupling of BA, which is the key to realizing satisfied HB selectivity (100 %). Theoretical simulations reveal that the weak adsorption of CH(OH)Ph radical over catalyst and the high energy barrier of over-oxidation of CH(OH)Ph into benzaldehyde contributes to the formation of highly selective coupling products. This work will inspire new insights to design rational photoredox systems for organic transformations with high selectivity.

Photocatalytic reduction of CO2 to methane (CH4) is a promising strategy to address CO2 emissions and energy scarcity. However, low efficiency limits its practical application. This study presents a bimetallic co-doping strategy using Cu and Co to enhance the photocatalytic performance of the In2O3 catalyst. The InCu0.05Co0.05Ox (InCuCo) catalyst demonstrated a CH4 yield of 22.3 µmol·g−1·h−1, outperforming In2O3 (8.8 µmol·g−1·h−1), InCu (14.5 µmol·g-1·h−1), and InCo (18.0 µmol·g-1·h−1). This remarkable improvement highlights the synergistic effects of Cu and Co in the In2O3 catalyst. Characterizations and density functional theory (DFT) calculations revealed that Co doping narrows the bandgap of the catalyst, enhancing light utilization, while Cu adjusts the energy band positions and improves CO2 adsorption. Consequently, the InCuCo catalyst significantly enhances the photocatalytic reduction of CO2–CH4, offering remarkable activity and stability. These results provide new insights into CO2 photoreduction to CH4, facilitating further practical applications.

In this study, a Cu2O/TiO2 (CuTi) visible-light photocatalytic composite was employed for the treatment of Xanthomonas campestris and X. campestris-infected Brassica napus seedlings. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against X. campestris were determined to be 8 and 32 mu g ml(-1), respectively. Transmission electron microscopy analysis demonstrated a direct correlation between the extent of bacterial cell damage and the concentration of CuTi. Noteworthily, a bactericidal rate of 100% was achieved at a concentration of 150 mu g ml(-1) over a treatment duration of 120 min. Moreover, alterations in active oxidants and antioxidants, including reactive oxygen species, glutathione reductase, superoxide dismutase, peroxidase, and catalase within the bacterial cells, were examined to elucidate the underlying mechanism of inhibition by the CuTi. The B. napus infected by X. campestris was treated with CuTi, and the efficacy was validated through determination of plant resistance indexes. The combined data confirmed that the CuTi is characterized by a low dose, fast onset, good effect, and higher safety for killing X. campestris, and it is expected to be developed as an antimicrobial agent for vegetables.

Acinetobacter baumannii (A. baumannii) was widely existed in medical wastewater and easily induced infections to threaten the human healthy. We herein reported Ag/CoO-N photocatalyst composites for effective inactivation of A. baumannii. Ag/CoO-N composites were prepared by N-doping to CoO crystal in supercritical fluid followed with photo-reduction of Ag under visible-light irradiation. N-species was incorporated in the crystal structure of CoO, on which uniform Ag nanoparticles were stably deposited. Thus, the satisfactory photocatalytic sterilization of A. baumannii irradiated by visible-light irradiation was attributed to the high capability of light trapping and the efficient separation of photo-charges. Due to photo-induced electrons as the main active species, Ag nanoparticles and CoO-N synergistically realized mineralization of cell membrane, which lead K+ ions leak from cell to crack structure of bacteria, the decrease of genetic materials, and the cripple of the self-repair function in bacteria, resulting in the final cell death.

Photocatalytic membrane reactor (PMR), coupling photocatalysis and membrane separation, has shown a considerable potential in foulant removal. However, the serious membrane fouling and fragile membrane stability still limit the application of current PMR systems. Here, we report a strategy that PdCu alloy deposited on TiO2, which is incorporated with polyvinylidene fluoride membrane, achieves high humic acid (HA) rejection efficiency (100%) with enhanced membrane permeation and anti-fouling performance. Detailed characterizations demonstrate that alloying effect of PdCu-TiO2 plays multiple roles in improving PMR performance: (1) providing the paired Pd-Cu sites for enhancing HA adsorption and transferring electrons from Pd-Cu sites to HA to improve photocatalytic HA removal; (2) inducing the photothermal effect due to the carrier damping, which directly enhances membrane permeation. The remarkable properties of PdCu-TiO2 membrane in PMR confirm the significance of alloying effect for treating aqueous organic pollutants.

Membrane technologies offer great potential in desalination and wastewater treatment. However, the serious issue of membrane fouling results in the unsatisfactory sustainability and reusability for treating wastewater containing high level of organic foulants. In this work, a photocatalytic membrane reactor system combining Ag@BiOBr photocatalyst and polyvinylidene fluoride (PVDF) ultrafiltration with remarkable anti-fouling property was constructed. The integrated Ag@BiOBr/PVDF photocatalytic ultrafiltration membranes were prepared by blending Ag@BiOBr nanoparticles (NPs) into PVDF membrane via phase inversion method. The membrane separation performance and fouling resistance were studied in a cross-flow ultrafiltration system using bovine serum albumin (BSA) as the model foulants. Compared with the pristine PVDF membrane, the hydrophilicity and surface smoothness of composite membranes were promoted by photocatalyst-incorporation, the Ag@BiOBr/PVDF membrane with the optimal Ag@BiOBr blending content of 2.0 wt% achieved both enhanced water flux and higher BSA rejection efficiency. More importantly, the mechanism of anti-fouling and self-cleaning performances were further studied, the photocatalysis process based on Ag@BiOBr/PVDF membrane effectively decomposed the BSA foulant into broken protein with induced change of carbonyl, ionic bond and hydrogen bond contents in BSA foulants via the active radicals, weakened the intermolecular force of BSA foulants to prevent membrane pore blockage. Meanwhile, the broken protein peptide chains with more negative charges could result in the strength of electrostatic repulsive forces between BSA molecules and membrane. As a result, the BSA foulant could be stably removed in the Ag@BiOBr/PVDF photocatalytic ultrafiltration system under visible light irradiation, achieving the excellent anti-fouling performance by preventing the membrane pore blockage and foulant adhesion. We believe the Ag@BiOBr/PVDF photocatalytic membrane presented in this study will be one example among many photocatalyst-membrane combinations that can be further pursued for organic pollutants removal. In particular, we expect the theoretical support can present a great opportunity to design novel photocatalytic membranes with sustainable anti-fouling performance.

In our rapidly expanding society, the demand for clean water has steadily emerged as one of the most critical issues, promoting the development of numerous water treatment strategies. Coupling photocatalysis and membrane separation technology provides an energy saving and environment-friendly as well as sustainable method for aqueous pollutants removal due to the synergetic enhanced pollutant removal efficiency and improved anti-fouling performance. It is of great scientific and technical significance to construct multifunctional photocatalysis-membrane separation reactor systems (PMRs) with both the high photocatalytic activity and the strong stability. Herein, in order to introduce the recent advances of this field, we present a critical review on developments of PMRs for aqueous pollutant removal, which includes photocatalysts and membranes, advanced methods for designing PMRs. Meanwhile, the recent applications of PMRs in aqueous pollutant removal, antifouling strategies, and mechanisms have also been summarized, including the latest development of PMRs coupling with other treatment methods. Furthermore, future perspective of PMRs is outlooked and predicted. PMRs, designed for the removal of aqueous pollutants, offer a more promising solution for the sustainable development of our society in the future.

The coordinated removal of pollutants in wastewater, especially metal ions and organic pollutants, is regarded as a tough challenge and has focused wide attentions. Synergistic photocatalytic-photothermal route is a powerful technology for the potential wastewater treatment. Herein, we designed a synergistic photocatalytic-photothermal system based on two-dimensional Ti3C2Tx MXene (TCM) membrane for simultaneous recovery of Ag+ ions and removal of aqueous rhodamine B (RhB). The photo-reduction of Ag+ ions into Ag nanoparticles with the conversion rate up to 100% was achieved on TCM membrane under visible-light irradiation. These Ag nanoparticles uniformly deposited on the surface and interlayers of TCM membrane. It facilitated the separation of photo-generated charges for forming more active species, including both ∙O2- and ∙OH radicals, to oxide RhB molecular. At the same time, the surface plasma effect of Ag nanoparticles enhanced the light adsorption and photothermal conversion efficiency (∼81%) on the TCM membrane. Conversely, photothermal effect was beneficial for further enhancing the reaction rate of both reduction of Ag+ ions and photo-oxidation of RhB by concentrating the solution and promoting the electron transfer. The novelty of the synergistic photocatalytic-photothermal contribution is significant for simultaneous recovery of metal ions and removal of organic pollutants in wastewater.

The influence of metal ions, the state of metal salt, and ligands on the sterilization ability of (Metalorganic frameworks) MOFs to effectively achieve sterilization has been investigated in this study. Initially, the MOFs were synthesized by elements of Zn, Ag, and Cd for the same periodic and main group of Cu. This illustrated that the atomic structure of Cu was more beneficial for coordinating with ligands. To further induce the maximum amount of Cu2+ ions in the Cu-MOFs to achieve the highest sterilization, various Cu-MOFs synthesized by the different valences of Cu, various states of copper salts, and organic ligands were performed, respectively. The results demonstrated that Cu-MOFs synthesized by 3, 5-dimethyl-1, 2, 4-triazole and tetrakis (acetonitrile) copper(I) tetrafluoroborate presented the largest inhibition-zone diameter of 40.17 mm towards Staphylococcus Aureus (S. aureus) under dark conditions. The proposed mechanism of Cu (Ⅱ) in MOFs could significantly cause multiple toxic effects, such as the generation of reactive oxygen species, and lipid peroxidation in S. aureus cells, when the bacteria was anchored by the Cu-MOFs via electrostatic interaction. Finally, the broad antimicrobial properties of Cu-MOFs against Escherichia coli (E. coli), Acinetobacter baumannii (A. baumannii), and S. aureus were demonstrated. In conclusion, the Cu-3, 5-dimethyl-1, 2, 4-triazole MOFs appeared to be potential antibacterial catalysts in the antimicrobial field.

Aiming to remove the organic pollutant in wastewater, carbon nitride (C3N4)/graphene oxide (GO) hybrid loaded on three-dimensional (3D) melamine foam (MF) (C3N4/GO@MF) nanocomposites was constructed, achieving the synergistic adsorption-photocatalysis effect. The macroporous structure of MF provided the efficient mass contact and the light transfer. C3N4 was in-situ polymerized on GO nanosheets, which was deposited on the framework of MF. The uniform distribution of C3N4/GO inhibited the accumulation of powder catalyst and achieved the high specific surface area, leading to the enhanced adsorption ability. More importantly, the stable interaction between C3N4 and GO facilitated the visible light harvesting and the separation of photo-induced charges. As a result, the effective removal of rhodamine B (RhB) was realized by the synergistic adsorption-photocatalysis effect of C3N4/GO@MF composite. The visible-light photocatalytic efficiency of C3N4 was further improved by the excellent electrical conduction of GO nanosheets. This work presented the significance of free-standing photocatatalytic composites with 3D framework for the potential application for the removal of aqueous organic pollutants.

Cu2O/TiO2 visible-light photocatalytic composite was successfully synthesized by supercritical solvothermal route. Cu2O/TiO2 presented excellent bacterial inactivation activity for Pseudomonas marginalis pv. marginalis, which was related to the concentration of bacteria and the antibacterial time. The highest sterilization ratio reached up to 100% when the bacteria was treated with 80 μg/mL of Cu2O/TiO2 photocatalytic composite for 80 min, which could be further proved by the damage of integrity and shrink of the cell membrane in transmission electron microscopy (TEM) image. When the bacterial concentration was 1 × 105 CFU/mL, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined as 16 and 32 μg/mL by agar dilution, respectively. Meanwhile, the production of reactive oxygen species (ROS), glutathione reductase (GR) and glutathione (GSH) of Pseudomonas marginalis pv. marginalis treated by Cu2O/TiO2 were determined by DCFH-DA, DTNB and kinetic method, respectively, to evaluate the anti-oxidation capacity of bacteria cell. The enzyme activity of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) in bacteria treated with Cu2O/TiO2 were measured to further confirm the overproduction of ROS. Cu2O/TiO2 was demonstrated as the excellent visible-light photocatalyst for efficiently killing Pseudomonas marginalis pv. marginalis with the low dosage. Finally, the Cu2O/TiO2 composite photocatalytic material was applied to cucumber seedlings based on field experimental, and its inhibitory effect in practical application was judged by measuring the morphology, enzyme activity and resistance index of cucumber plants. It is of great significance to the practical application as a suitable and powerful antibacterial agent for Pseudomonas marginalis pv. marginalis and other bacteria.

A new type of ZIF-67/ZnO hybrid coated on Co foil was prepared via an electrochemical etching and hydrothermal processes for photoelectrocatalytic sterilization. The thorn-like ZnO nanorods in the photoanode films play an important role of capturing bacteria from solution. The porous ZIF-67 with high specific surface area efficiently adsorbed the leaked K+ ions assisted by the hERG release, and realizes the visible-light photocatalytic activity with the generation of charge carriers. The visible-light photoelectrocatalytic antibacterial effect on ZIF67/ZnO hybrid is further promoted by applying a potential to the photoelectrode to promote the separation and transfer of charge carriers. As a result, the visible-light photoelectrocatalytic antibacterial effect was powerful for rapid destroy of cell integrity. At the same time, the decomposition of bacteria cell was also facilitated to further accelerate the K+ leakage. Thus, the simultaneous process of destroying cell membrane integrity and leaking K+ ions is achieved during the photoelectrocatalytic process, leading to the complete destruction of bacteria. This photoelectrocatalytic antibacterial system based on ZIF-67/ZnO@Co foil offers a potential way for sterilization application in the future.