Solar-driven reduction of dinitrogen (N ) to ammonia (NH ) is severely hampered by the kinetically complex and energetically challenging multielectron reaction. Oxygen vacancies (OVs) with abundant localized electrons on the surface of bismuth oxybromide-based semiconductors are demonstrated to have the ability to capture and activate N , providing an alternative pathway to overcome such limitations. However, bismuth oxybromide materials are susceptible to photocorrosion, and the surface OVs are easily oxidized and therefore lose their activities. For realistic photocatalytic N fixation, fabricating and enhancing the stability of sustainable OVs on semiconductors is indispensable. This study shows the first synthesis of self-assembled 5 nm diameter Bi O Br nanotubes with strong nanotube structure, suitable absorption edge, and many exposed surface sites, which are favorable for furnishing sufficient visible light-induced OVs to realize excellent and stable photoreduction of atmospheric N into NH in pure water. The NH generation rate is as high as 1.38 mmol h g , accompanied by an apparent quantum efficiency over 2.3% at 420 nm. The results presented herein provide new insights into rational design and engineering for the creation of highly active catalysts with light-switchable OVs toward efficient, stable, and sustainable visible light N fixation in mild conditions.

The synthesis of highly crystalline covalent triazine frameworks (CTFs) with ultrastrong covalent bonds (aromatic CN) from the triazine linkage presents a great challenge to synthetic chemists. Herein, the synthesis of highly crystalline CTFs via directly controlling the monomer feeding rate is reported. By tuning the feeding rate of monomers, the crystallization process can be readily governed in a controlled manner in an open system. The sample of CTF‐HUST‐HC1 with abundant exposed {001} crystal facets has the better crystallinity and thus is selected to study the effect of high crystallinity on photoelectric properties. Owing to the better separation of photogenerated electron–hole pairs and charge transfer, the obtained highly ordered CTF‐HUST‐HC1 has superior performance in the photocatalytic removal of nitric oxide (NO) than its lesser crystalline counterparts and g‐C3N4.

In this study, we demonstrate that the photocatalytic sodium pentachlorophenate removal efficiency of Bi2WO6 under visible light can be greatly enhanced by bismuth self-doping through a simple soft-chemical method. Density functional theory calculations and systematical characterization results revealed that bismuth self-doping did not change the redox power of photogenerated carriers but promoted the separation and transfer of photogenerated electron-hole pairs of Bi2WO6 to produce more superoxide ions, which were confirmed by photocurrent generation and electron spin resonance spectra as well as superoxide ion measurement results. We employed gas chromatography-mass spectrometry and total organic carbon analysis to probe the degradation and the mineralization processes. It was found that more superoxide ions promoted the dechlorination process to favor the subsequent benzene ring cleavage and the final mineralization of sodium pentachlorophenate during bismuth self-doped Bi2WO6 photocatalysis by producing easily decomposable quinone intermediates. This study provides new insight into the effects of photogenerated reactive species on the degradation of sodium pentachlorophenate and also sheds light on the design of highly efficient visible-light-driven photocatalysts for chlorophenol pollutant removal.

Photoreduction of CO 2 to fuels offers a promising strategy for managing the global carbon balance using renewable solar energy. But the decisive process of oriented photogenerated electron delivery presents a considerable challenge. Here, we report the construction of intermolecular cascaded π-conjugation channels for powering CO 2 photoreduction by modifying both intramolecular and intermolecular conjugation of conjugated polymers (CPs). This coordination of dual conjugation is firstly proved by theoretical calculations and transient spectroscopies, showcasing alkynyl-removed CPs blocking the delocalization of electrons and in turn delivering the localized electrons through the intermolecular cascaded channels to active sites. Therefore, the optimized CPs (N-CP-D) exhibiting CO evolution activity of 2247 μmol g −1 h −1 and revealing a remarkable enhancement of 138-times compared to unmodified CPs (N-CP-A).

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