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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]

Aside from the electrolyte, a separator is another important component in lithium‐based batteries that has a direct impact on the safety feature and electrochemical performances. To overcome the thermal shrinkage and poor electrolyte affinity of commonly used polyolefin separators, cellulose‐based separators are appealing due to their abundant polar functional groups, thermal stability, and environmental friendliness, especially for large‐sized and high‐energy‐density batteries. Herein, a porous three‐dimensional (3D) network of polymer cellulose‐based separator (denoted as PIC) modified with polyethyleneimine (PEI) and polyvinylidene fluoride‐hexafluoropropylene (PVDF‐HFP) was prepared using a non‐solvent induced phase separation approach. The lithium metal batteries consisting of a PIC separator can deliver a specific capacity of up to 114 mAh g−1 even at a high C‐rate of 8 C (1.36 A g−1) after 300 cycles. Such superior performances of the lithium metal batteries can be attributed to the good wetting ability (390 % electrolyte absorption) and high ionic conductivity (0.754 mS cm−1) of the as‐prepared PIC separator. More importantly, the introduction of polyethyleneimine as a cross‐linking agent significantly improves the mechanical strength of the separator, promotes the uniform deposition of lithium, and compatibility with high voltage (4.4 V) cathode materials LiNi0.8Mn0.1Co0.1O2. This work demonstrates a new strategy for the separator design for high‐performance lithium metal battery applications. [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]

Keywords: fruit waste; molybdenum carbide; photothermal materials; solar evaporation; sustainable EN fruit waste molybdenum carbide photothermal materials solar evaporation sustainable 1 1 1 01/11/23 20230109 NES 230109 B Freshwater production b using solar-driven interfacial evaporation is regarded as a green and sustainable strategy. Herein, we present a facile two-step carbonization approach that is sustainable for developing innovative two-dimensional molybdenum carbide (Mo SB 2 sb C) materials derived from carbonized fruit wastes. [Extracted from the article]

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]