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Hybrid Cuprous oxide-silver (Cu 2 O-Ag) have attracted tremendous attention due to their various applications in photocatalysis, surface enhanced Raman scattering (SERS), and optical features. Here we expanded the application to exhibit excellent chemical stability and synergistic bactericidal. We prepared Cu 2 O-Ag heterostructure through thermally decomposing Ag-acetate to deposit Ag nanoparticles (Ag NPs) onto Cu 2 O surface. Cu 2 O-Ag heterostructure bears exceptional stability while exposing to oxygen, water, and light, owing to the physical coating of Ag NPs and transferring the electrons and holes inside the Cu 2 O to the surface through a Schottky barrier to prevent photocorrosion. The deposition of Ag NPs also improved the intensity and time of oxidative stress reaction of Cu 2 O, proved by reactive oxygen species (ROS) examination. Ag NPs distributed on the surface of Cu 2 O particles formed a large of ion release channel, resulting in excellent sustained release of copper ions. Density functional theory (DFT) calculations were used to investigate the mechanism of photocatalysis and ROS generation. The constructed Cu 2 O-Ag heterostructure exhibit highly long-term sterilization activity against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) which were maintained around 70% and 80% and were increased by 40% and 50% compared with free Cu 2 O after being immersed in phosphate buffer saline (PBS) solutions within 14 days., (Copyright © 2019 Elsevier Inc. All rights reserved.)

With the rapid development of economy, water pollution becomes a serious threat to people's lives and health. It is urgent to exploit a method to achieve rapid and long-term stability water disinfection. Herein, the branched CuO-Co 3 O 4 nanowires (NWs) were first prepared on the foamed copper substrate, afterwards coated a layer of carbon film on NWs to obtain the innovative CuO-Co 3 O 4 @C NWs filter, which remarkably elevated the sterilization property and superior long-term stability. As a result, the resulting CuO-Co 3 O 4 @C NWs filter, based on electroporation and reactive oxygen species (ROS) sterilization technology, had an extremely sterilization efficiency of 99.5% for Escherichia coli and Staphylococcus aureus at a flow rate of 1000 mL min-1 and an external voltage of 10 V. More importantly, the filter had excellent bactericidal stability. After 12 h of continuous operation, the efficiency remained above 80%, which was not possible with the previously reported electroporation technology. This rapid and long-time stability water disinfection material has great potential in practical applications in the future. The filter of 3D CuO-Co 3 O 4 @C NWs electrode with composite structure has been successfully prepared and innovatively used for water disinfection, which achieves excellent sterilization efficiency with high flow rate and ensures the stability of the electrode. [Display omitted] • Innovatively prepared 3D NWs electrode. • The 3D CuO-Co 3 O 4 @C NWs electrode significantly increases the position of the enhanced electric field. • The 3D CuO-Co 3 O 4 @C NWs electrode has unprecedented long-term sterilization performance at high flow rates. [ABSTRACT FROM AUTHOR]

[Display omitted] • The loading content of SA in the PUF microcapsules was approximately 40%. • The antibacterial rates of SA@PUF after 35 days against S. aureus and P. aeruginosa remained at 80 % and 81 %, increased by 60 % and 62 % compared with pure SA, respectively. • The long-term antibacterial mechanisms were the toxicity of SA and the continuous generation of ROS. • The SA@PUF coating exhibited the excellent anti-corrosion property with |Z| 0.01Hz of 5.51 GΩ cm2. • The SA@PUF coating was effective in an actual marine environment. This work successfully synthesized the salicylic acid@polyurea-formaldehyde (SA@PUF) microcapsules with PUF microcapsules as shell material and SA as core material. The loading content of SA in the PUF microcapsules was approximately 40 %. The SA@PUF microcapsules had excellent long-term antibacterial properties because the PUF microcapsules controlled the release of SA antifouling agents with the ability to induce reactive oxygen species generation and inactivate bacteria. The antibacterial efficiency of SA@PUF microcapsules after 35 days against Staphylococcus aureus and Pseudomonas aeruginosa remained at 80 % and 81 %, increased by 60 % and 62 % compared with pure SA, respectively. The impedance modulus at 0.01 Hz of the SA@PUF coating reached 5.51 GΩ cm2, much higher than blank coating (2.55 GΩ cm2) and PUF coating (4.94 GΩ cm2), indicating that the anti-corrosion property of the SA@PUF coating was much better. This work would contribute to developing novel coatings with long-term antibacterial activity and excellent anti-corrosion performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu 2 O NWs@NC electrode is proposed as a novel and effective alternative Cu 2 O NWs. • Cu 2 O NWs@NC electrodes have high conductivity and ROS species (e-, OH and O 2 –) in the antibacterial system. • N -doped carbon layer enhances the stability and has lower toxicity compared with Cu 2 O NWs. • Cu 2 O NWs@NC electrodes achieve high flow rates and long-term disinfection under low energy consumption. High-speed, low-cost and long-term water disinfection method is important for us to away from waterborne diseases. Nanowires-modified electrodes can inactivate microorganisms under low energy consumption. However, small processing capacity remains a major obstacle for practical application. In this study, we coated N -doped carbon layer on Cu 2 O NWs to improve the conductivity and stability for electrodes. Compared with Cu 2 O, the work functions of Cu 2 O-PANI structures is 3.623 eV, indicating the electrodes can prevent the recombination of electron-hole pairs and improve the carrier transport efficiency. In addition, Mulliken charge density showed that Cu 2 O-PANI structure reduce the oxidation trend of Cu atom and improve the stability of electrodes. Besides, the Cu 2 O NWs@NC electrodes showed excellent disinfection performance for E. coli and S. aureus , which can achieve 99.9% sterilizing rate under high flux (1200 mL min−1). Under this condition, the electrodes can continuously treat 576 L wastewater, which is about 10-folds handling capacity than others. Moreover, the bactericidal mechanism is synergistic of electroporation and reactive oxygen species, and the main ROS were electrons, OH and O 2 –. Therefore, this electrodes has a great prospect for rapid and stable water treatment system. [ABSTRACT FROM AUTHOR]

The synergistic effect of MXene separation of photogenerated electrons, COF photocatalysis, Ag antibacterial, Ag+ sustained release, ROS. [Display omitted] It is a major challenge to combine the advantages of two kinds of two-dimensional materials to construct a heterojunction and achieve efficient photocatalytic antifouling. In this work, we covalently connected two materials MXenes and covalent organic frameworks (COFs) through the Schiff base reaction and anchored Ag nanoparticles (NPs) to prepare a Ti 3 C 2 /TpPa-1/Ag composite material with high efficiency bactericidal properties. The covalent bonding between MXene and COF greatly improved the stability of the material. Ti 3 C 2 /TpPa-1/Ag composite showed an excellent antibacterial property against S. aureus and P. aeruginosa. The fluorescence spectra of Ti 3 C 2 /TpPa-1/Ag proved that the electron transfer channels formed between the ternary materials could greatly improve the efficiency of carrier separation and prolong the life of photogenerated carriers. Density functional theory calculations showed that the synergistic catalytic effect of Ag and Ti 3 C 2 could greatly reduce the work function along the interface, and the built-in electric field between the layers drive carrier fast migration, which effectively improve the catalytic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] Harmful bacterial flourish with the increase in environmental pollution and pose a great threat to human health. Thus, developing new and efficient antibacterial materials is imperative to reduce the pollution caused by traditional sterilization materials and improve sterilization efficiency. In this study, a new photocatalytic antibacterial material was developed to achieve an efficient antibacterial effect. Ti 3 C 2 T x @CuS composites were synthesized by simple hydrothermal method, by which copper sulfide (CuS) nanoparticles were anchored on the surface of Ti 3 C 2 T x to sharply improve the photocatalytic its antibacterial ability. Ti 3 C 2 T x @CuS exhibits excellent antibacterial activity against Escherichia coli and Staphylococcus aureus with bactericidal rates of 99.6% and 99.1%, respectively. Photoluminescence spectroscopy (PL), decay time PL, photocurrent test, electrochemical impedance spectroscopy and finite element method showed that the formation of Ti 3 C 2 T x @CuS heterojunction promoted the separation of electrons and holes, improved the electron transport efficiency, and elevated the generation of reactive oxygen species. Moreover, Ti 3 C 2 T x @CuS has a stronger photothermal effect and causes more heat release than CuS to improve antibacterial performance. The Ti 3 C 2 T x @CuS heterojunction has a broad application prospect in the disinfection and antibacterial fields. [ABSTRACT FROM AUTHOR]

The Ag@Cu 2 O heterostructure core-shell nanostructure can achieve the sterilization of reactive oxygen groups under visible light. [Display omitted] Marine biological fouling has always been a hot research topic. In this study, silver @ cuprous oxide (Ag@Cu 2 O) core-shell nanoparticles were synthesized via in-situ synthesis method and developed an outstanding antibacterial activity. The bacteriostasis efficiency of Ag@Cu 2 O reached to 99% and 98% against Staphylococcus aureus and Pseudomonas aeruginosa , respectively. The minimum inhibitory concentration of Ag@Cu 2 O decreased from 113.6 μg/mL to 56.8 μg/mL compared with Cu 2 O. Ag@Cu 2 O had better antibacterial activity than Cu 2 O with lower content of Cu 2 O and was more environment friendly. The heterostructure formed at the interface between Ag and Cu 2 O promoted the separation and diffusion of photogenerated electron-hole pairs through the charge transfer channel and promoted the generation of reactive oxygen species. The outstanding antibacterial activity of Ag@Cu 2 O was strongly depended on the generation of the reactive oxygen species. Density functional theory and finite element method calculations demonstrated that the structure of core-shell improved photocatalytic efficiency. Additionally, synergetic effect of released Ag+ and Cu2+ also enhanced the bacteriostasis rate and the long-term antifouling performance in 60 days. Hence, the synthesized core-shell Ag@Cu 2 O can be applied as novel antifoulants in the marine field. [ABSTRACT FROM AUTHOR]

Low photocatalytic efficiency of visible light and fast recombination of photo-generated carriers are two challenges facing the applications of photocatalyst sterilant zinc oxide (ZnO). Meanwhile, both light and dark photocatalytic activities are important. It is of great theoretical and practical significance to construct a day-night photocatalytic antibacterial material, which is beneficial to the effective use of energy and to tackle the limitation of using photocatalytic bacteriostat. ZnO nanoflowers decorated vanadium pentoxide (V 2 O 5) nanowires heterojunction (ZVH) was firstly fabricated using a facile water-bathing method. The designed ZVH structure efficiently produced abundant reactive oxygen species (ROS) in both light and darkness. It yielded 99.8% and 99.0% of antibacterial rate against S. aureus due to oxidative stress induced by ROS in light and darkness, respectively. The generation of ROS played a major role in the antibacterial activities against S. aureus under both light and dark conditions. The prepared ZVH with improved antibacterial properties provides an alternative for day-night antibacterial agents. [ABSTRACT FROM AUTHOR]

• Ag@CeO 2 @Ti 3 C 2 heterojunction was prepared by hydrothermal method. • Bacteriostatic efficiencies of the Ag@CeO 2 @Ti 3 C 2 heterojunction against E. coli and S. aureus reached 97.94% and 97.25%. • Enhanced photocatalytic bacteriostatic properties of CeO 2 was modified by Ti 3 C 2 MXene and Ag NP. An Ag@CeO 2 @Ti 3 C 2 heterojunction was prepared by hydrothermal method. The bacteriostatic efficiencies of Ag@CeO 2 @Ti 3 C 2 against E. coli and S. aureus are 2.96 times higher than that of pure CeO 2 , showing an excellent bacteriostatic activity. The formation of heterojunction was beneficial to photoelectron transfer and inhibited the recombination of photogenerated carriers. Moreover, the heterostructure promoted the production of reactive oxygen species to improve the bacteriostatic performance, and achieved a photocatalytic bacteriostatic effect. The synthesis method of Ag@CeO 2 @Ti 3 C 2 and its photocatalytic mechanism could provide a broad application prospect in CeO 2 bacteriostatic fields and semiconductors modification. [ABSTRACT FROM AUTHOR]

The synergistic effect of MXene separation of photogenerated electrons, COF photocatalysis, Cu 2 O antibacterial, Cu2+ sustained release, ROS. [Display omitted] • Covalently bonded MXene/COF heterojunction materials were prepared by Schiff base reaction. • The change of photocatalytic bactericidal performance due to Cu 2 O anchored were carried out. • The work function perpendicular to the interface was greatly reduced by the DFT. • Ti 3 C 2 /TpPa-1/Cu 2 O composite had bactericidal effect against S. aureus and P. aeruginosa under visible light irradiation. Reasonably combining the advantages of heterojunction constructed by a variety of two-dimensional materials and metal oxide nanoparticles (NPs) is an effective strategy to improve the efficiency of photocatalytic sterilization. In this work, TpPa-1-COF, as a stable semiconductor, was in situ grown on Ti 3 C 2 -MXene through the Schiff base reaction and anchored with Cu 2 O NPs to obtain an efficient photocatalytic bactericide. Electrochemical impedance spectroscopy and photoluminescence spectra of nanocomposites showed that the photogenerated carrier migration rate as well as the production of reactive oxygen species was improved and the carrier life was prolonged. The work function at the interface was analyzed by using the first principle calculation based on density functional theory. Both TpPa-1/Ti 3 C 2 interface and Ti 3 C 2 /Cu 2 O interface had large built-in electric field to promote the migration of carriers between layers, so as to realize efficient photocatalysis and reduce photo-corrosion. The obtained Ti 3 C 2 /TpPa-1/ Cu 2 O nanocomposites showed excellent antibacterial rates against S. aureus and P. aeruginosa , which were antibacterial rates of 98.90% and 99.62% and were increased by 50% and 33% compared with pure TpPa-1-COF. It provides a new idea for the development of photocatalytic bactericides in the field of marine antifouling. [ABSTRACT FROM AUTHOR]

Synergistic effect of MXene accelerating photoelectron transportation, Cu 2 O antimicrobial and photocatalysis, ROS, surface plasmon resonance and uniform dispersion of MXene. • A Cu 2 O anchored MXene nanosheet as heterojunction structure was synthesized. • Cu 2 O uniformly anchored on the surface of MXene due to electrostatic effect. • Cu 2 O/MXene nanosheets display an admirable synergistic antibacterial behavior. • Cu 2 O/MXene shows an antibacterial effect of photocatalysis, ROS and SPR. Ti 3 C 2 T x (MXene) as a two-dimensional material has attracted numerous attentions in photocatalysis and antibacterial, and the effectiveness of MXene for photocatalysis triggered antibacterial is in urgent need of development. Herein, we synthesized a novel cuprous oxide (Cu 2 O) anchored MXene nanosheet. Cu 2 O nanospheres can be uniformly anchored on the surface of MXene firmly due to the electrostatic effect between single-layer MXene and Cu 2 O nanospheres. In comparison with MXene, Cu 2 O and mixture (MXene and Cu 2 O), Cu 2 O/MXene nanosheet exhibits an excellent antibacterial activity against S. aureus and P. aeruginosa , whose bacteriostasis efficiencies sharply increased to 97.04% and 95.59%, respectively. Photoluminescence spectroscopy reveals that the incorporation of MXene and Cu 2 O can effectively prevent the recombination of electron-hole pairs of Cu 2 O and present a high photocatalytic disinfection. Single-layer MXene with large surface area accepts electrons from Cu 2 O, leading to abundant electrons on the surface of MXene, which provide better charge transfer between bacteria and Cu 2 O/MXene nanosheets. In addition, density functional theory calculations were used to investigate an optimized band structure of Cu 2 O-MXene as well as its strong electronic interactions, which are essential for photocatalysis and ROS generation. Finite element method further revealed that MXene promoted an enhancement of surface plasmon resonance to generate ROS on the surface of Cu 2 O/MXene. Furthermore, Cu 2 O/MXene shows a synergistic antibacterial effect of MXene accelerating photoelectron transportation, Cu 2 O antimicrobial and photocatalysis, elevated ROS production ability, and surface plasmon resonance action on the surface of Cu 2 O/MXene. [ABSTRACT FROM AUTHOR]

The nanostructure can achieve the synergistic sterilization of electroporation and active oxygen under the action of electric field. After treatment, Escherichia coli lost a smooth cell membrane structure and had obvious electroporation holes on the surface. • The novel C/Cu 2 O-AgNPs structure are prepared by simple impregnation method. • The C/Cu 2 O-AgNPs structure electrodes have high-conductivity. • The C/Cu 2 O-AgNPs structure electrodes achieve high flow rates with low voltage. • The antibacterial mechanism of the electrode is unraveled. Water safety is closely related to the human health, an efficient and low-cost water disinfection method is far-reaching for all kinds of water supplies. However, how to achieve convenient and efficient water disinfection is still an open question. Herein, we firstly prepared a hierarchical Cu 2 O nanowires covered by silver nanoparticles-doped carbon layer on Cu foam (C/Cu 2 O-AgNPs) in a simplified one-step impregnation method. And it is confirmed that the fabricated three-dimensional structure with carbon layer which was embed into silver nanoparticles exhibits excellent conductivity than that with silver nanoparticles-loaded carbon layer. The filter combined with selected C/Cu 2 O-AgNPs materials achieved 99.6% sterilizing rate against Escherichia coli and Staphylococcus aureus under external voltage of 10 V with 1200 mL min−1 flow rates. Based on the analyses of experimental results and finite element simulations, the efficient sterilization with high flow rate comes from the strong adhesion of AgNPs embedding in the carbon layer and the enhanced conductivity of electrodes due to the improved electronic transmission in the contact of AgNPs and Cu 2 O nanowires. This rapid water disinfection will have a great potential in future practical application. [ABSTRACT FROM AUTHOR]