Shifting electrochemical oxygen reduction reaction (ORR) via two‐electron pathway becomes increasingly crucial as an alternative/green method for hydrogen peroxide (H2O2) generation. Here, the development of 2e− ORR catalysts in recent years is reviewed, in aspects of reaction mechanism exploration, types of high‐performance catalysts, factors to influence catalytic performance, and potential applications of 2e− ORR. Based on the previous theoretical and experimental studies, the underlying 2e− ORR catalytic mechanism is firstly unveiled, in aspect of reaction pathway, thermodynamic free energy diagram, limiting potential, and volcano plots. Then, various types of efficient catalysts for producing H2O2 via 2e− ORR pathway are summarized. Additionally, the catalytic active sites and factors to influence catalysts’ performance, such as electronic structure, carbon defect, functional groups (O, N, B, S, F etc.), synergistic effect, and others (pH, pore structure, steric hindrance effect, etc.) are discussed. The H2O2 electrogeneration via 2e− ORR also has various potential applications in wastewater treatment, disinfection, organics degradation, and energy storage. Finally, potential future directions and prospects in 2e− ORR catalysts for electrochemically producing H2O2 are examined. These insights may help develop highly active/selective 2e− ORR catalysts and shape the potential application of this electrochemical H2O2 producing method.

Substituting natural products for traditional poison-killing antifouling agents is an efficient and promising method to alleviate the increasingly serious ecological crisis and aggravate the loss due to marine biofouling. Herein, the successful synthesis of poly­(methyl methacrylate-co-ethyl acrylate-co-hexafluorobutyl methacrylate-co-isobornyl methacrylate) copolymer (PBAF) with borneol monomers and fluorine by a free radical polymerization method is reported. The PBA0.09F coating exhibits outstanding antibacterial and antifouling activity, achieving 98.2% and 92.3% resistance to Escherichia coli and Staphylococcus aureus, respectively, and the number of Halamphora sp. adhesion is only 26 (0.1645 mm2) in 24 h. This remarkable antibacterial and antifouling performance is attributed to the incorporation of fluorine components into the copolymer, which induces a low surface energy and hydrophobicity and the complex molecular structure of the natural nontoxic antifouling agent borneol. In addition, the results showed that the contents of the adhesion-related proteins mfp-3, mfp-5, and mfp-6 were significantly reduced, which proved that natural substances affect the secretion of biological proteins. Importantly, the PBAF coating exhibits excellent environmental friendliness and long-term stability. The antifouling mechanism is clarified, and an effective guide for an environmentally friendly antifouling coating design is proposed.

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Endowing metallic surfaces with special wettability and unique interfacial contacts broadens their wide application fields. Herein, superhydrophobic and lubricant-infused ultraslippery surfaces were achieved through chemical etching, low surface energy molecule grafting, and lubricant infusion. Systematic comparison studies of the surface wettability, self-cleaning, anti-icing, anticorrosion behaviors, and mechanical durability were carried out to reveal the functional differences and mechanisms. Both superhydrophobic and ultraslippery surfaces exhibit a distinct decrease in ice adhesion strength and a remarkable increase in charge-transfer resistance, demonstrating significantly improved ice overdelay and corrosion-resisting performance. Most notably, given the existence of a stable, defect-free, and inert lubricant-infused layer, the lubricant-infused ultraslippery surfaces possess superior mechanical robustness and long-term corrosion resistance, which provides better application potential under challenging service environments.

current, and transferred charges were measured by an electrometer (Keithley 6514). A high-speed camera (Photron FASTCAM Mini AX) was applied to record the vibration state of the STS under the agitation of water current.

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Discovering novel materials and improving the properties of existing materials are the main goals in the field of photocatalysis to increase the potential application of the materials. In this paper, a modified graphitic carbon nitride (g-C3N4) photocatalyst named Fe3+-doped alkalized carbon nitride, which couples the photocatalytic reaction with the Fenton reaction, is introduced to demonstrate its Rhodamine B (RhB) degradation and antibacterial properties. Under visible-light irradiation, the degradation rate of RhB was 99.9% after 200 min, while the antibacterial rates of Pseudomonas aeruginosa (P. aeruginosa), Escherichia coli (E. coli), and Staphylococcus aureus (S. aureus) after 300 min were 99.9986%, 99.9974%, and 99.9876%, respectively. Moreover, the repetitive experiments of RhB degradation demonstrate that the proposed photocatalysts have excellent stability and reusability. The active free radical trapping experiments reveal that the superoxide radical (·O2−) is the dominant reactive oxygen species. In addition, the Fenton reaction is introduced into the photocatalytic system due to the doping of Fe3+, and the hydroxyl radical (·OH) produced from the Fenton reaction further enhances the photocatalytic performance. The remarkable improvement in photocatalytic performance of the proposed photocatalyst can be attributed to its broader UV–visible absorption characteristic and the occurrence of the Fenton reaction.

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