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A novel 2D/0D C3N5/Bi2WO6 S-scheme heterojunction with enhanced structural defects has been designed for the efficient elimination of pharmaceutical antibiotics and Cr(vi).

In recent studies, phase junctions constructed as photocatalysts have been found to possess great prospects for organic degradation with visible light. In this study, we designed an elaborate rhombohedral corundum/cubic In

Photocatalytic water splitting is one of the promising approaches to solving environmental problems and energy crises. However, the sluggish 4e− transfer kinetics in water oxidation half-reaction restricts the 2e− reduction efficiency in photocatalytic water splitting. Herein, cobalt vanadate-decorated polymeric carbon nitride (named CoVO/PCN) was constructed to mediate the carrier kinetic process in a photocatalytic water oxidation reaction (WOR). The photocatalysts were well-characterized by various physicochemical techniques such as XRD, FT-IR, TEM, and XPS. Under UV and visible light irradiation, the O2 evolution rate of optimized 3 wt% CoVO/PCN reached 467 and 200 μmol h−1 g−1, which were about 6.5 and 5.9 times higher than that of PCN, respectively. Electrochemical tests and PL results reveal that the recombination of photogenerated carriers on PCN is effectively suppressed and the kinetics of WOR is significantly enhanced after CoVO introduction. This work highlights key features of the tuning carrier kinetics of PCN using charge-conducting materials, which should be the basis for the further development of photocatalytic O2 reactions.

Salt blocking and low evaporation efficiency under weak sun irradiation are two obstacles of solar-thermal seawater desalination in the industrialization process. Herein, the challenges are overcome by a solar-thermal interfacial membrane evaporation (STIME) system, i.e., combining merits of advanced thermal management of interfacial evaporation and salt insulation of membrane evaporation, simultaneously achieving salt-resistance, hydrovoltaic generation, and all-weather vapor generation. By employing a hybrid system based on sandwich -like MXene-graphene oxide-MXene (MGM) on a commercial PVDF membrane (MGM@PVDF), we achieved an evaporation efficiency up to 92.5% and without any salt accumulation for 10 h at 10 wt% NaCl solution. Moreover, the system can also be driven by Joule-heating effect for water evaporation under dark or cloudy conditions The maximum evaporation rate of this system driven by sunlight (0.5 sun) and electricity (36 V) can reach 10.5 kg m -2h- 1. Apart from water evaporation, the MGM@PVDF modules possess excellent molecular sieve effect and can pretreat dye pollution before desalination. Furthermore, the MGM@PVDF also exhibits excellent anti-bacterial effect and biocompatibility, ensuring ecological balance during real-world applications. Thus, the developed STIME system provides a novel avenue for all-weather steam generation to constantly provide safe drinking water. Refereed/Peer-reviewed

Conjugated polymers have gathered particular interests in photocatalysis because of their excellent properties such as optimization flexibility, cost-effective, and robust stability. The pyrene-based polymer (PyP), as one of the conjugated polymers, holds a great potential for water splitting because of their suitable band structure, visible light absorption, and high surface area. However, because of the fast charge carrier recombination confined by Frenkel excitons with high exciton binding energy, PyP in its pristine form remains barely active for photoctalytic hydrogen evolution. The concise construction of heterojunction is a feasible way to accelerate the charge separation, increase the lifetime of the photogenerated e−/h+ pair and decrease the activation barriers of hydrogen evolution reaction. In this work, a series of transition metal sulfides as cocatalysts have been deposited on PyP to construct heterojunctions for photocatalytic H2 evolution reaction (HER). The loading techniques (immersion, in-situ and photodeposition) and the loading contents of cocatalysts have been investigated. The optimized MoS2/PyP sample exhibited a 10-fold increase in comparison with pure PyP without modification. The extended π-conjugation, high surface area, and widely exposed 2D interface highlight the importance of PyP as effective supports for stabilizing the homogeneously dispersed MoS2, thereby resulting in an efficient photocatalytic activity. This study provides a new idea to construct low-cost, sustainable and efficient hybrid system for photocatalytic hydrogen production.

Polymeric carbon nitride (CN) is a promising material for photocatalytic water splitting. However, CN in its pristine form tends to show moderate activity due to fast recombination of the charge carriers. The design of efficient photocatalytic system is therefore highly desired, but it still remains a great challenge in chemistry. In this work, a pyrene-based polymer able to serve as an electron donor to accelerate the interface charge carrier transfer of CN is presented. The construction of donor-acceptor (D-A) heterojunction was confirmed to significantly restrain the charge recombination and, thus, improve the proton reduction process. This study provides a promising strategy to achieve solar H2 production in an efficient and low-cost manner.

Polymeric carbon nitride (CN) is a promising material for photocatalytic water splitting. However, CN in its pristine form tends to show moderate activity due to fast recombination of the charge carriers. The design of efficient photocatalytic system is therefore highly desired, but it still remains a great challenge in chemistry. In this work, a pyrene-based polymer able to serve as an electron donor to accelerate the interface charge carrier transfer of CN is presented. The construction of donor-acceptor (D-A) heterojunction was confirmed to significantly restrain the charge recombination and, thus, improve the proton reduction process. This study provides a promising strategy to achieve solar H

The rational cooperation of sustainable catalysts with suitable light-harvesting semiconductors to fabricate photosynthetic device/machinery has been regarded as an ideal technique to alleviate the current worldwide energy and environmental issues. Cobalt based species (e.g., Co-Pi, Co3O4, and Co-cubene) have attracted particular attentions because they are earth-abundant, cost-acceptable, and more importantly, it shows comparable water oxidation activities to the noble metal based catalysts (e.g., RuO2, IrO2). In this contribution, we compared two general cocatalysts modification strategies, based on the surface depositing and bulk doping of ultrafine cobalt species into the sustainable graphitic carbon nitride (g-C3N4) polymer networks for oxygenic photosynthesis by splitting water into oxygen, electrons, and protons. The chemical backbone of g-C3N4 does not alter after both engineering modifications; however, in comparison with the bulk doping, the optical and electronic properties of the surface depositing samples are efficiently promoted, and the photocatalytic water oxidation activities are increased owing to much more exposed active sites, reduced overpotential for oxygen evolution and the accelerated interface charge mobility. This paper underlines the advantage of surface engineering to establish efficient advanced polymeric composites for water oxidation, and it opens new insights into the architectural design of binary hybrid photocatalysts with high reactivity and further utilizations in the fields of energy and environment.

Here we report a facile impregnation synthesis of layered Co(OH)2 deposited with g-C3N4 while the pH value is adjusted by using ammonia solution for photocatalytic water oxidation with UV–vis and visible light illumination. This surface modification not only accelerates the interface transfer rate of charge carriers but also reduces the excessive energy barrier for O–O formation, thus leading to enhanced reaction kinetics for photocatalytic water oxidation. The optimum oxygen evolution rates (OERs) of the Co(OH)2/g-C3N4 sample reached 27.4 and 7.1 μmol h–1 under UV–vis (λ >300 nm) and visible light (λ >420 nm) irradiation, which are 5.5 and 7 times faster than those for pristine g-C3N4, respectively. These results underline the possibility for the development of effective, robust, and earth-abundant WOCs for the promotion of water-splitting photocatalysis by sustainable g-C3N4 polymer photocatalysts.

Cobalt selenide has been developed as an effective cocatalyst to decorate visible light photocatalysts, including WO3, BiVO4 and g-C3N4, establishing intense surface contact with substrates for the photocatalytic water oxidation reaction. Compared with CoOx and CoSx, CoSe2 is superior for improving the photocatalytic water oxidation activity due to the lower anionic electronegativity, which leads to dense adhesion and enables fast interfacial charge transfer for the water oxidation reaction.