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Artificial H2O2 photosynthesis by covalent organic frameworks (COFs) photocatalysts is promising for wastewater treatment. The effect of linkage chemistry of COFs as functional basis to photoelectrochemical properties and photocatalysis remains a significant challenge. In this study, three kinds of azoles‐linked COFs including thiazole‐linked TZ‐COF, oxazole‐linked OZ‐COF and imidazole‐linked IZ‐COF were successfully synthesized. More accessible channels of charge transfer were constructed in TZ‐COF via the donor‐π‐acceptor structure between thiazole linkage and pyrene linker, leading to efficient suppression of photoexcited charge recombination. Density functional theory calculations support the experimental studies, demonstrating that the thiazole linkage is more favorable for the formation of *O2 intermediate in H2O2 production than that of the oxazole and imidazole linkages. The real active sites in COFs located at the benzene ring fragment between pyrene unit and azole linkage. [ABSTRACT FROM AUTHOR]

Freshwater production using solar‐driven interfacial evaporation is regarded as a green and sustainable strategy. The biggest barrier to practical deployment of solar desalination, however, continues to be the lack of options for renewable materials. Herein, we present a facile two‐step carbonization approach that is sustainable for developing innovative two‐dimensional (2D) molybdenum carbide (Mo2C) materials derived from carbonized fruit wastes. The resultant 2D Mo2C photothermal layer has an efficient water evaporation rate of 1.52 kg m−2 h−1 with a photothermal conversion efficiency of 94 % under one sun irradiation, which is among the best reported values so far. The broad solar absorption band, high specific surface area (555.1 m2 g−1) with large micro‐ and meso porosity, of the Mo2C photothermal layer are responsible for these outstanding results. The conversion of food wastes into valuable products, in this case MXene, can potentially inspire greener developments of advanced materials for solar water evaporator. [ABSTRACT FROM AUTHOR]

Alloyed bismuth oxyhalides have been widely used in photocatalytic water treatment processes due to their superior photocatalytic activity. However, there is no report on the removal of NO3- for alloyed bismuth oxyhalides, and the mechanism of the effect of alloying on NO3- reduction activity is still unclear. In this work, we prepared a series of BiOClnBr1-n (0≤n≤1) with different Cl/Br ratios but with controlled similar morphologies, and explored their catalytic activities on reducing NO3- under visible light irradiation. Density functional theory investigations revealed that the formation energy for an oxygen (O) vacancy on the surface of BiOClnBr1-n alloys is clearly reduced in comparison with the monohalide, illustrating that more O vacancies can be produced on the surface of BiOClnBr1-n alloys. A high concentration of O vacancies not only promotes the adsorption of NO3- but also enhances the separation efficiency of the photogenerated electron-hole (e-h) pairs, with both being beneficial to enhance the photocatalytic activity of BiOClnBr1-n alloys for NO3- reduction. These new discoveries not only promote the design and development of new photocatalysts with excellent NO3- reduction properties, but also help to understand the relationship between alloying effects and semiconductor photocatalytic properties. [ABSTRACT FROM AUTHOR]

Zinc metal anodes encounter significant challenges, including dendrite growth, hydrogen evolution, and corrosion, all of which impede the rate capability and longevity of aqueous zinc-ion batteries (AZIBs). To effectively tackle these issues, we introduced Tween-80 into the traditional ZnSO 4 electrolyte as an additive. Tween-80 possesses electronegative oxygen atoms that enable it to adsorb onto the zinc (Zn) anode surface, facilitating the directional deposition of Zn metal along the (002) orientation. The hydroxyl and ether groups within Tween-80 can displace some of the coordinated water molecules in the Zn 2+ inner solvation shell. This disruption of the hydrogen bond network regulates the solvation structure of Zn 2+ ions and suppresses the possibility of hydrogen evolution. Moreover, the long hydrocarbon chain present in Tween-80 exhibits excellent hydrophobic properties, aiding in the resistance against corrosion of the Zn anode by water molecules and reducing hydrogen evolution. Consequently, a symmetric cell equipped with the Tween-80 additive can cycle stably for over 4000 h at 1 mA cm -2 and 1 mA h cm -2 . When paired with the V 2 O 5 cathode, the full cell demonstrates a high-capacity retention rate exceeding 80 % over 1000 cycles at a current density of 2 A g -1 . This study underscores the advantages of utilizing non-ionic surfactants for achieving high-performance aqueous zinc-ion batteries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Artificial H 2 O 2 photosynthesis by covalent organic frameworks (COFs) photocatalysts is promising for wastewater treatment. The effect of linkage chemistry of COFs as functional basis to photoelectrochemical properties and photocatalysis remains a significant challenge. In this study, three kinds of azoles-linked COFs including thiazole-linked TZ-COF, oxazole-linked OZ-COF and imidazole-linked IZ-COF were successfully synthesized. More accessible channels of charge transfer were constructed in TZ-COF via the donor-π-acceptor structure between thiazole linkage and pyrene linker, leading to efficient suppression of photoexcited charge recombination. Density functional theory calculations support the experimental studies, demonstrating that the thiazole linkage is more favorable for the formation of *O 2 intermediate in H 2 O 2 production than that of the oxazole and imidazole linkages. The real active sites in COFs located at the benzene ring fragment between pyrene unit and azole linkage., (© 2023 Wiley-VCH GmbH.)

Freshwater production using solar-driven interfacial evaporation is regarded as a green and sustainable strategy. The biggest barrier to practical deployment of solar desalination, however, continues to be the lack of options for renewable materials. Herein, we present a facile two-step carbonization approach that is sustainable for developing innovative two-dimensional (2D) molybdenum carbide (Mo 2 C) materials derived from carbonized fruit wastes. The resultant 2D Mo 2 C photothermal layer has an efficient water evaporation rate of 1.52 kg m -2  h -1 with a photothermal conversion efficiency of 94 % under one sun irradiation, which is among the best reported values so far. The broad solar absorption band, high specific surface area (555.1 m 2  g -1 ) with large micro- and meso porosity, of the Mo 2 C photothermal layer are responsible for these outstanding results. The conversion of food wastes into valuable products, in this case MXene, can potentially inspire greener developments of advanced materials for solar water evaporator., (© 2022 Wiley-VCH GmbH.)