Piao Xu

Phase engineering of transition-metal dichalcogenides provides a powerful means to regulate atomic-scale catalysis, yet the role of interfacial electronic structures in controlling reaction kinetics remains unclear. Here, we demonstrate that phase-dependent Mo–S–Fe interfacial coupling in MoS₂ induces pronounced interfacial polarization, accelerating dual Fe/Mo redox cycles during peroxymonosulfate (PMS) activation. Atomic resolution differential phase contrast scanning transmission electron microscopy (DPCSTEM) directly visualizes isolated Fe single atoms and polarized charge redistribution at the Fe–S–Mo interface in metallic 1TMoS₂, whereas the 2H phase favors Fe₃O₄ nanoparticle formation. Density functional theory calculations reveal that strong interfacial coupling shortens the Fe–S bond, promotes charge delocalization, and lowers the kinetic barriers for Fe and Mo redox transitions. Consequently, Fe–1T MoS₂ exhibits greatly enhanced PMS activation, with reaction rate constants up to 0.62min⁻¹, exceeding those of 2H phase catalysts by over two orders of magnitude.

Regulating metal‐support interactions enables rational design of catalysts with enhanced performance in Fenton‐like oxidation reactions. Here, a novel oxygen‐doped, stalactite‐like g‐C₃N₄ supported FeOCl (FeOCl‐OCN) is successfully synthesized. Due to the modulation of O doping to the work function (Φ) of g‐C₃N₄ support, a delicate built‐in electric field (BIEF) oriented from OCN to FeOCl is constructed. Driven by large work function difference (ΔΦ = 3.235 eV), the interfacial charge transfer manipulates electron redistribution to achieve a rearrangement of structural Fe(II)/Fe(III). Based on theoretical calculations and mechanism insight, the interaction between FeOCl and OCN exhibits a stronger binding ability to peroxymonosulfate (PMS) and reduces the energy barriers for *O formation, therefore favoring a higher yield of singlet oxygen (¹O₂) and high‐valent iron‐oxo (Fe(IV)═O)− species. As a result, the FeOCl‐OCN/PMS system demonstrates a nonradical‐dominated pathway, delivering high activity (k _obs = 0.250 min⁻¹), robust tolerance to pH variation and resistance, and excellent stability.

A triplex DNA electrochemical sensor based on reduced graphene oxide (rGO) and electrodeposited gold nanoparticles (EAu) was simply fabricated for Pb²⁺ detection. The glass carbon electrode (GCE) sequentially electrodeposited with rGO and EAu was further modified with a triplex DNA helix that consisted of a guanine (G)-rich circle and a stem of triplex helix based on T-A•T base triplets. With the existence of Pb²⁺, the DNA configuration which was formed via the Watson–Crick and Hoogsteen base pairings was split and transformed into a G-quadruplex. An adequate electrochemical response signal was provided by the signal indicator methylene blue (MB). The proposed sensor demonstrated a linear relationship between the differential pulse voltammetry (DPV) peak currents and the logarithm of Pb²⁺ concentrations from 0.01 to 100.00 μM with a detection limit of 0.36 nM. The proposed sensor was also tested with tap water, river and medical wastewater samples with qualified recovery and accuracy and represented a promising method for Pb²⁺ detection.

Metal–organic frameworks (MOFs) are solid crystalline materials formed by the self-assembly of organic ligands and metal ions or clusters. Combining the advantages of membrane separation and MOFs, MOFs-based membranes are used in water treatment.

In recent years, using semiconductor photocatalysts for antibiotic contaminant degradation under visible light has become a hot topic. Herein, a novel and ingenious cadmium-doped graphite phase carbon nitride (Cd-g-C₃N₄) photocatalyst was successfully constructed via the thermal polymerization method. Experimental and characterization results revealed that cadmium (Cd) was well doped at the g-C₃N₄ surface and exhibited high intercontact with g-C₃N₄. Additionally, the introduction of cadmium significantly improved the photocatalytic activity, and the optimum degradation efficiency of tetracycline (TC) reached 98.1%, which was exceeded 2.0 times that of g-C₃N₄ (43.9%). Meanwhile, the Cd-doped sample presented a higher efficiency of electrical conductivity, light absorption property, and photogenerated electron-hole pair migration compared with g-C₃N₄. Additionally, the quenching experiments and electron spin-resonance tests exhibited that holes (h⁺), hydroxyl radicals (•OH), superoxide radicals (•O₂⁻) were the main active species involved in TC degradation. The effects of various conditions on photocatalytic degradation, such as pH, initial TC concentrations, and catalyst dosage, were also researched. Finally, the degradation mechanism was elaborated in detail. This work gives a reasonable point to synthesizing high-efficiency and economic metal-doped photocatalysts.

Versatile types of MOF-derived mixed transition metal nanomaterials are summarized in terms of synthetic routes. The applications of those materials in energy storage and conversion, including LIBs, SCs, ORR, OER and HER are discussed.