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Singlet oxygen (1O2) is an essential reactive species responsible for selective oxidation of organic matter, especially in Fenton‐like processes. However, due to the great limitations in synthesizing catalysts with well‐defined active sites, the controllable production and practical application of 1O2 remain challenging. Herein, guided by theoretical simulations, a series of boron nitride‐based single‐atom catalysts (BvBN/M, M=Co, Fe, Cu, Ni and Mn) were synthesized to regulate 1O2 generation by activating peroxymonosulfate (PMS). All the fabricated BvBN/M catalysts with explicit M−N3 sites promoted the self‐decomposition of the two PMS molecules to generate 1O2 with high selectivity, where BvBN/Co possessed moderate adsorption energy and d‐band center exhibited superior catalytic activity. As an outcome, the BvBN/Co‐PMS system coupled with membrane filtration technology could continuously transform aromatic alcohols to aldehydes with nearly 100 % selectivity and conversion rate under mild conditions, suggesting the potential of this novel catalytic system for green organic synthesis. [ABSTRACT FROM AUTHOR]

Copper (Cu) is evidenced to be effective for constructing advanced catalysts. In particular, Cu2O is identified to be active for general catalytic reactions. However, conflicting results regarding the true structure‐activity correlations between Cu2O‐based active sites and efficiencies are usually reported. The structure of Cu2O undergoes dynamic evolution rather than remaining stable under working conditions, in which the actual reaction cannot proceed over the prefabricated Cu2O sites. Therefore, the dynamic construction of Cu2O active sites can be developed to promote catalytic efficiency and reveal the true structure‐activity correlations. Herein, by introducing the redox pairs of Cu2+ and reducing sugar into a photocatalysis system, it is clarified that the Cu2O sub‐nanoclusters (NCs), working as novel active sites, are on‐site constructed on the substrate via a photoinduced pseudo‐Fehling's route. The realistic interfacial charge separation and transformation capacities are remarkably promoted by the dynamic Cu2O NCs under the actual catalysis condition, which achieves a milestone efficiency for nitrate‐to‐ammonia photosynthesis, including the targets of production rate (1.98±0.04 mol gCu−1 h−1), conversion ratio (94.2±0.91 %), and selectivity (98.6 %±0.55 %). The current work develops an effective strategy for integrating the active site construction into realistic reactions, providing new opportunities for Cu‐based chemistry and catalysis sciences research. [ABSTRACT FROM AUTHOR]

To date, the chemical conversion of organic pollutants into value‐added chemical feedstocks rather than CO2 remains a major challenge. Herein, we successfully developed a coupled piezocatalytic and advanced oxidation processes (AOPs) system for achieving the conversion of various organic pollutants to CO. The CO product stems from the specific process in which organics are first oxidized to carbonate through peroxymonosulfate (PMS)‐based AOPs, and then the as‐obtained carbonate is converted into CO by piezoelectric reduction under ultrasonic (US) vibration by using a Co3S4/MoS2 catalyst. Experiments and DFT calculations show that the introduction of Co3S4 not only effectively promotes the transfer and utilization of piezoelectric electrons but also realizes highly selective conversion from carbonate to CO. The Co3S4/MoS2/PMS system has achieved selective generation of CO in actual complex wastewater treatment for the first time, indicating its potential practical applicability. [ABSTRACT FROM AUTHOR]

The universal limit on the pH conditions is disturbing peroxymonosulfate (PMS)‐triggered high‐valent iron‐oxo systems in environmental applications. Here, we propose for the first time the construction of a neutral microenvironment on the surface of Zn−Fe layered double hydroxide (ZnFe‐LDH) by using the amphoteric properties of zinc hydroxide, which continuously generates ≡FeIV=O over a wide pH range of 3.0–11.0 in activating PMS. The ≡Zn(OH)2 moiety offers a neutral microenvironment at the phase interface, which mitigates the self‐decomposition of ≡FeIV=O by protons and the hydrolysis reaction of iron by hydroxyl groups, which is supported by the Mossbauer spectra, density functional theory calculations and designed experiments. Consequently, ZnFe‐LDH/PMS can satisfy the stability in long‐term experiments, selectivity under conditions with high salinity or natural organic matter and efficient treatment of actual wastewater. [ABSTRACT FROM AUTHOR]

Although Fenton or Fenton‐like reactions have been widely used in the environment, biology, life science, and other fields, the sharp decrease in their activity under macroneutral conditions is still a large problem. This study reports a MoS2 cocatalytic heterogeneous Fenton (CoFe2O4/MoS2) system capable of sustainably degrading organic pollutants, such as phenol, in a macroneutral buffer solution. An acidic microenvironment in the slipping plane of CoFe2O4 is successfully constructed by chemically bonding with MoS2. This microenvironment is not affected by the surrounding pH, which ensures the stable circulation of Fe3+/Fe2+ on the surface of CoFe2O4/MoS2 under neutral or even alkaline conditions. Additionally, CoFe2O4/MoS2 always exposes "fresh" active sites for the decomposition of H2O2 and the generation of 1O2, effectively inhibiting the production of iron sludge and enhancing the remediation of organic pollutants, even in actual wastewater. This work not only experimentally verifies the existence of an acidic microenvironment on the surface of heterogeneous catalysts for the first time, but also eliminates the pH limitation of the Fenton reaction for pollutant remediation, thereby expanding the applicability of Fenton technology. [ABSTRACT FROM AUTHOR]

It is important to develop self‐producing reactive oxygen species (ROSs) systems and maintain the continuous and effective degradation of organic pollutants. Herein, for the first time, a system of ultrasound‐treated CoS2−x mixed with Fe2+ is constructed to sustainably release singlet oxygen (1O2) for the effective degradation of various organic pollutants, including dyes, phenols, and antibiotics. Ultrasonic treatment produces defects on the surface of CoS2 which promote the production of ROSs and the circulation of Fe3+/Fe2+. With the help of Co4+/Co3+ exposed on the surface of CoS2−x, the directional conversion of superoxide radical (.O2−) to 1O2 is realized. The CoS2−x/Fe2+ system can degrade organic pollutants efficiently for up to 30 days, which is significantly better than the currently recognized CuPx system (<3 days). Therefore, CoS2−x provides a new choice for the long‐term remediation of organic pollutants in controlling large area river pollution. [ABSTRACT FROM AUTHOR]

3D‐MoS2 can adsorb organic molecules and provide multidimensional electron transport pathways, implying a potential application for environment remediation. Here, we study the degradation of aromatic organics in advanced oxidation processes (AOPs) by a 3D‐MoS2 sponge loaded with MoS2 nanospheres and graphene oxide (GO). Exposed Mo4+ active sites on 3D‐MoS2 can significantly improve the concentration and stability of Fe2+ in AOPs and keep the Fe3+/Fe2+ in a stable dynamic cycle, thus effectively promoting the activation of H2O2/peroxymonosulfate (PMS). The degradation rate of organic pollutants in the 3D‐MoS2 system is about 50 times higher than without cocatalyst. After a 140 L pilot‐scale experiment, it still maintains high efficiency and stable AOPs activity. After 16 days of continuous reaction, the 3D‐MoS2 achieves a degradation rate of 120 mg L−1 antibiotic wastewater up to 97.87 %. The operating cost of treating a ton of wastewater is only US$ 0.33, suggesting huge industrial applications. [ABSTRACT FROM AUTHOR]

Hollow structures with an efficient light harvesting and tunable interior component offer great advantages for constructing a Z-scheme system. Controlled design of hollow cobalt sulfide (Co9S8) cubes embedded with cadmium sulfide quantum dots (QDs) is described, using hollow Co(OH)2 as the template and a one-pot hydrothermal strategy. The hollow CdS/Co9S8 cubes utilize multiple reflections of light in the cubic structure to achieve enhanced photocatalytic activity. Importantly, the photoexcited charge carriers can be effectively separated by the construction of a redox-mediator-free Z-scheme system. The hydrogen evolution rate over hollow CdS/Co9S8 is 134 and 9.1 times higher than that of pure hollow Co9S8 and CdS QDs under simulated solar light irradiation, respectively. Moreover, this is the first report describing construction of a hollow Co9S8 based Z-scheme system for photocatalytic water splitting, which gives full play to the advantages of light-harvesting and charges separation. [ABSTRACT FROM AUTHOR]