Single-atom catalysts (SACs)-based peroxymonosulfate (PMS) systems are highly selective to the type of organic pollutants while the mechanisms remain ambiguous. In this work, we carried out experimental and theoretical investigations to reveal the origins of selectivity of radical and nonradical pathways in a designated Co−N 4 −C/PMS system. Two typical pollutants [bisphenol A (BPA) and metronidazole (MNZ)] with different molecular structures were employed for comparison. We found that radical oxidation (SO 4•− and HO • ) and nonradical electrontransfer pathway (ETP) co-existed in the Co−N 4 −C/PMS system. Pollutants (e.g., MNZ) with a high redox potential were degraded primarily by free radicals rather than ETP, while the oxidization of low-redox pollutants (e.g., BPA) was dominated by ETP at the surface region of Co−N 4 −C which overwhelmed the contributions of radicals in the homogeneous phase. Intriguingly, the contributions of radical and nonradical pathways could be manipulated by the PMS loading, which simultaneously increased the radical population and elevated the oxidation potential of Co−N 4 −C-PMS* complexes in ETP. Findings from this work will unravel the mysterious selective behavior of the SACs/PMS systems in the oxidation of different micropollutants.

Thiomolybdate [Mo3S13]2– nanoclusters anchored on reduced graphene oxide-carbon nanotube (rGO-CNTs) aerogels were used as a new catalyst for efficient electrocatalytic hydrogen evolution. The elemental distribution of sulfur (S) corresponded well to the Mo distribution, and both Mo and S elements distributed evenly in the Mo3S13@rGO-CNTs aerogels. Results indicated that [Mo3S13]2– nanoclusters inherently exposed a high number of active edge sites, which greatly improved the electrocatalytic hydrogen evolution. The new peak at 168.8 eV corresponded to the characteristic S–O binding in the S 2p region of Mo3S13@rGO-CNTs, indicating that the [Mo3S13]2– clusters were bond onto the rGO-CNTs aerogels through S–O binding. The strong support of rGO-CNTs aerogels suppressed the aggregation of [Mo3S13]2– nanoclusters, exposing more active surface and electrons diffusions on the surface of Mo3S13@rGO-CNTs aerogels. Mo3S13@rGO-CNTs aerogels laden with 20 mg of [Mo3S13]2– exhibited close hydrogen evolution reaction (HER) performance as compared with that of [Mo3S13-120]@rGO-CNTs aerogels laden with 120 mg of [Mo3S13]2– nanoclusters. This indicated the extremely high HER performance of [Mo3S13]2– even at low mass. As a result, Mo3S13@rGO-CNTs aerogels enabled remarkable electrochemical performances showing a low overpotential (0.179 V at 10 mA cm–2) with a small Tafel slope, reduced transfer resistance, and excellent stability.

Ultrathin graphitic carbon nitride (gCN) nanosheets, due to their two-dimensional graphene-like structure, regularly distributed triangular nanopores and structural defects on the laminar network, have attracted great research attention in fabricating high-performance water selective membranes.

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Solar-driven evaporation of water to produce clean water is a promising solution to alleviate the water crisis. Herein, a novel three-dimensional (3D) interconnection porous structure and ultra-light maize straw/graphene aerogel...