The photocatalytic coupling of selective phenylcarbinol oxidation with hydrogen evolution has attracted considerable attention as a promising dual-functional reaction system. Herein, a lattice-matched 2D/3D NiS/CdIn2S4 (NiS/CIS) Schottky heterojunction is rationally designed for efficient dual-functional photocatalysis under visible light. Structural analyses confirm the uniform deposition of NiS nanosheets on octahedral CIS with a lattice mismatch below 5%, ensuring coherent interfacial contact. The optimal 3% NiS/CIS composite exhibits exceptional hydrogen and benzaldehyde production rates of 2636.4 and 2717.6μmolg-1h-1, respectively-representing enhancements of 39.7 and 38.0 times over pristine CIS. The catalyst also demonstrates remarkable stability, retaining over >99.0% activity after six cycles. Mechanistic studies reveal that the Schottky junction facilitates spatial separation of photogenerated carriers: electrons migrate to NiS, prolonging charge carrier lifetimes and lowering the hydrogen evolution overpotential, while holes accumulate on CIS that facilitated phenylcarbinol adsorption to drive selective phenylcarbinol oxidation via a carbon-radical pathway. This work provides a viable approach for designing efficient bifunctional photocatalysts through lattice-matched interface engineering.

The core innovation of this study lies in the construction of an indirect glycerol oxidation coupled with hydrogen (H 2 ) evolution system mediated by the Cu 2+ /Cu + redox pathway. By leveraging the spontaneous reduction of the Cu(OH) 2 pre-catalyst with glycerol, the latter is converted into high-value products such as glycerate and formate. The resulting Cu + species are subsequently electrooxidized back to Cu 2+ , establishing a continuous Cu 2+ /Cu + redox cycle that effectively bypasses the high overpotential limitations of traditional direct oxidation pathways. X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), and operando Raman spectroscopy confirm that, under alkaline conditions, glycerol efficiently reduces Cu(OH) 2 to Cu 2 O, ensuring the sustainability of the Cu + electrooxidation process. This mechanism lowers the anodic onset potential to 0.65 V RHE (versus reversible hydrogen electrode), approximately 1 V below that required for OER, achieving a "low-potential-driven" reaction. A coupled Cu(OH) 2 /CF || Pt/C cell delivers 100 mA cm⁻ 2 at a H 2 production energy demand of only 2.7 kWh m⁻ 3 H 2 , exceeding 50% reduction than that required in the conventional water electrolysis (5.6 kWh m⁻ 3 H 2 ). In alkaline media, glycerol spontaneously and rapidly reduces the pre-catalyst Cu(OH) 2 to Cu 2 O (Cu + ), while it is itself oxidized to the valuable products, formate and glycerate. These Cu + species is then electro-oxidized back to Cu 2+ , establishing a continuous Cu 2+ /Cu + redox cycle that enables the indirect upgrading oxidation of glycerol at a low potential and effectively bypasses the high overpotential limitation of the conventional direct oxidation route. • Glycerol spontaneously reduces Cu(OH) 2 to Cu 2 O in alkaline medium. • Indirect glycerol oxidation via Cu 2+ /Cu + redox shuttle is achieved. • This system lowers the anodic onset potential to 0.65 V RHE , ~1 V below than that of OER. • Low-voltage H 2 production and glycerol valorization are simultaneously achieved.

TFA-mediated oxidative dehydrogenative coupling of quinoxalinones with edaravone and its analogs

This study proposes an integrated oxidative coupling of methane (OCM) process for the co-production of ethylene and hydrogen, aiming to overcome the limitations of conventional single-reactor OCM and improve system-level performance while addressing resource sustainability in ethylene production. The proposed processes employ a two-stage isothermal reaction system to improve methane conversion and C 2 selectivity, combined with an alternative separation strategy and on-site energy recovery via combined heat and power integration. Rigorous process simulations were conducted to establish mass and energy balances, followed by comprehensive techno-economic and environmental analysis. The optimal configuration achieved an ethylene unit production cost of 0.97 USD/kg, representing a 55.9% reduction relative to a conventional single-reactor OCM benchmark (2.2 USD/kg), driven by staged conversion, elimination of methane recycles, and hydrogen coproduction. Net CO 2 -equivalent emissions were reduced by 66.2% to 4.50 kg CO 2 per kg C 2 H 4 . Sensitivity analysis identified hydrogen value, methane price, and the methane/oxygen ratio as key determinants of economic feasibility. A multi-metric assessment incorporating energy use, carbon efficiency, feedstock availability, and price elasticity shows that methane-based direct conversion pathways exhibit favorable structural characteristics, particularly in terms of feedstock robustness. These results provide practical solutions to cost-competitively diversify resources for ethylene production, while leveraging emerging hydrogen markets. • Two-stage OCM reactors improve methane conversion and ethylene selectivity. • A developed process enables co-production of ethylene and hydrogen. • Ethylene unit production cost reaches 0.97 $/kg, 55.9% lower than benchmark. • Net CO 2-eq emissions reduced to 4.50 kg CO 2 per kg of ethylene, 66.2% improvement. • Multi-metric assessment supports methane-based routes for sustainable ethylene production.

ConspectusThe direct oxidation of methane, which is the main component of natural gas, shale gas, methane clathrates, and biogas, to value-added products is an economically attractive and environmentally friendly alternative to strongly endothermic methane steam reforming to synthesis gas (CO/H2). Among the different routes, the oxidative coupling of methane (OCM) to ethylene/ethane (C2-hydrocarbons) is the most promising one. A key limiting factor is insufficiently high selectivity to C2-hydrocarbons due to their overoxidation to carbon oxides (COx) at industrially relevant degrees of methane conversion. Although it is generally agreed that both selective and unselective reactions are initiated by oxygen species on the surface of catalysts, the kind, role, and origin of these species remain elusive, which hampers the tailored design of catalysts.In this Account, we summarize our recent progress in understanding how product selectivity in the OCM reaction can be tuned by controlling the type of oxygen species through catalyst composition or reaction conditions. The combination of in situ time- and temperature-resolved catalyst characterization with transient kinetic methods, i.e., temporal analysis of products (TAP) and steady-state isotopic transient kinetic analysis (SSITKA), has been proven to be effective for understanding the origin and role of oxygen species involved in selective and unselective pathways. We also present strategies for regulating the concentrations of selective and unselective oxygen species. For the Mn-M(M = Na, K, Rb, or Cs)2WO4 system, the electronegativity of the alkali metal was found to influence the ability of the catalysts to form selective oxygen species from gas-phase oxygen. The binding strength of atomic oxygen species is a key parameter for hindering the oxidation of methane to COx over Gd2O3-based catalysts. This property can be adjusted by using a metal oxide promoter. The nature and concentration of different oxygen species can also be controlled through the use of steam or an alternative oxidizing agent, N2O, and by performing the OCM reaction in a chemical looping mode, i.e., by alternating between CH4- and air-containing feeds. Using steam in the latter option enabled us to largely enhance the productivity of C2-hydrocarbons, thus making this technology more attractive for large-scale applications. The knowledge summarized in this Account is expected to present insights for further studies in the development of selective catalysts for various alkane oxidation reactions and in the optimization of reactor operation.

Oxygen Defect Engineering of SrTiO ₃ Catalysts for Oxidative Coupling of Methane

The integration of polyoxometalates (POMs) into metal-organic frameworks (MOFs) to construct composite photocatalysts represents a promising strategy for organic synthesis. The photosensitive [W10O32]4- clusters (noted as W10) were assembled with the La-MOF framework at the molecular level, successfully constructing a series of W10@MOF composites. These materials not only endow La-MOF with visible-light absorption capacity but, more importantly, significantly promote the separation and migration efficiency of photogenerated electron-hole pairs. In the photocatalytic amine oxidation coupling reaction, W10@MOF-4, with the largest W10 loading amount, exhibits excellent catalytic performance. Under mild conditions and without the need for an external oxidant, it achieves a benzylamine conversion rate of 98% and an imine selectivity of >99%, outperforming the single component and demonstrating a significant synergistic catalytic effect. Through systematic photoelectrochemical characterization, including photocurrent response, electrochemical impedance, and solid ultraviolet diffuse reflection analysis, it was confirmed that the introduction of W10 effectively regulated the material's energy band structure and significantly enhanced the interface charge separation efficiency as an electron capture center, providing a key mechanism basis for its outstanding photocatalytic performance.

Abstract Direct and selective upgrading of methane to multicarbon hydrocarbons under mild conditions remains one of the most compelling yet elusive goals spanning chemistry, energy, and environmental science. Solar-driven photocatalysis now offers an avenue to activate the inert C–H bonds of methane at ambient temperature and pressure; however, a clear, comparative mechanistic understanding of oxidative coupling versus non-oxidative coupling remains lacking, hindering rational catalyst design and pathway optimization. This review systematically dissects the photocatalytic reaction mechanisms of oxidative versus non-oxidative coupling, outlines key challenges associated with catalyst efficiency, selectivity, and stability, and highlights promising research directions for both pathways. The primary objective of this review is to further advance photocatalytic methane conversion technologies and to provide strategic guidance for the rational design of high-performance photocatalysts.

ABSTRACT The photocatalytic oxidative coupling of methane (OCM) offers a sustainable pathway for converting methane into valuable C2 compounds under ambient conditions. We explore the movement of oxygen species in photocatalytic OCM, particularly the cooperative effects between inert supports loaded with Au and semiconductor compounds (ZnO/TiO 2 , ZTO). The experimental results demonstrate that the coexistence of Au and ZTO is essential for C 2 H 6 production, even without any direct interfacing between the two components. EPR characterization indicates that superoxide radicals (·O 2 − ) may migrate from ZTO to Au sites, forming active Au─O species which activate methane into methyl radicals (·CH 3 ) for subsequent coupling into C 2 H 6 . Interestingly, in the photocatalytic OCM system, the C 2 H 6 yield remained stable upon progressive reduction of the semiconductor content before eventually declining. This trend suggests saturation of ·O 2 − intermediates likely arising from the kinetic balance between generation and quenching of ·O 2 − , where the semiconductor mediates the conversion of O 2 and lattice oxygen to ·O 2 − . We interpret this self‐regulating phenomenon as an Oxygen‐Mediated Self‐Buffering (O‐MSB) mechanism.

Steering the O2 photoactivation for boosting the generation of reactive oxygen species (ROSs) with moderate oxidant strength is crucial for fine organic synthesis, while it remains a huge challenge. Herein, by constructing a pair of metal-organic frameworks (MOFs) with isomeric linkers, i.e., Ni-TTPz-α and Ni-TTPz-β, we demonstrate the first achievement in modulating the chromophore linker torsional angle in MOFs for the precise regulation of ROSs generation. Ni-TTPz-α is equipped with a coplanar conjugated α-thiophene linker, while Ni-TTPz-β features misalignment between the bithiophene and pyrazole moieties due to the zigzag configuration of the β-linker. As a result, Ni-TTPz-α significantly boosts the production of superoxide radicals (O2•-) under visible light in air, whereas Ni-TTPz-β exclusively generates singlet oxygen (1O2) with much lower performance. The boosted generation of O2•- empowers Ni-TTPz-α to efficiently drive the oxidative coupling of benzylamine to imine, achieving a 99% yield within 12 h, which is significantly boosted than that of Ni-TTPz-β (48%). Experiments and theoretical calculations jointly confirm that planar α-thiophene features an angle-induced restricted twist effect that facilitates efficient electron transfer from the thiophene sulfur to the pyrazole unit and, ultimately, to the metal center, thereby driving single-electron oxygen reduction to produce O2•-.

Methanol aqueous reforming reaction (APRM) provides a green and clean route towards hydrogen production, in which the structure design and preparation of efficient catalysts remains a challenge. Herein, we report a platinum catalyst supported on the porous hydroxyl lanthanum oxide, which is prepared via glycine combustion method followed by a reduction process. The optimized 0.8%Pt/La catalyst, which is featured by Pt single-atom dispersed on a La2(OH)2 xO3-2 x support, exhibits an extraordinary catalytic performance towards APRM. A H2 production rate of 7672 µmolH2 gcat -1 min-1 and an average turnover frequency (ATOF) of 11973 h‒1 are obtained, which is preponderant to the state-of-the-art catalysts. An in-depth investigation based on kinetic isotope analysis, in situ spectroscopy characterizations and theoretical calculations substantiates that Pt single atom coordinated with adjacent lattice hydroxyl (OHL) with electron transfer from Pt to support serves as the intrinsic active site, in which the Ptδ + site promotes the dehydrogenation of methoxyl whilst lattice hydroxyl directly participates in the oxidative coupling process (CH2O* + OHL → CH2OOH*). Furthermore, the Ptδ +-(OHL)x-La interface sites can remarkably reduce the energy barrier of CH2OOH* dehydrogenation (rate-determining step), and the resulting hydroxyl vacancies can boost H2O dissociation to recover consumed OHL, accounting for the exceptional catalytic performance.

Arsenic (As) contamination in paddy soils threatens global food security because microbial reduction of arsenate (As(V)) to mobile arsenite (As(III)) drives As mobilization. Methane (CH4)-dependent As(V) reduction (M-AsR) is a key route coupling CH4 cycling to As release, yet how structurally distinct soil organic matter (SOM) fractions regulate this pathway remains poorly understood. Here we show that an aromatic, quinone-rich humic acid fraction enhances electron transfer and promotes coupling of CH4 oxidation to As(V) reduction, accelerating iron (Fe)-As mineral dissolution and increasing As(III) release by ∼1.5-fold. Accordingly, copy numbers of NC10-targeted pmoA, ANME-2d-targeted mcrA, and arrA increased by 116.6%, 126.5%, and ∼2.4-fold, respectively. In contrast, a carboxyl-rich fulvic fraction promoted acetate accumulation, thereby making CH4-driven metabolism thermodynamically unfavorable. NC10-targeted pmoA and ANME-2d-targeted mcrA signals consequently decreased by 95.3% and 89.6%, respectively, and M-AsR was largely blocked, with the CH4-driven As(III) component increasing by only 47.9%. Crucially, humic acid acts as an electron shuttle linking CH4 oxidation and As(V) reduction, while fulvic acid disrupts this coupling process via acetate accumulation, highlighting the need for molecular-level SOM characterization to predict As risks in flooded soils.

Anaerobic coupling of Sb(III) and sulfur oxidation by prokaryotes drives acidification in stibnite systems

Biochar-mediated sustainable remediation of petroleum-contaminated soil: From total petroleum hydrocarbon degradation to microbial responses.

ABSTRACT Thioester and amide are versatile functional groups commonly found in synthetic compounds, natural products, and functional materials, and they function as a crucial intermediate in organic transformations. The development of mild and efficient synthetic approaches provides a straightforward route to structurally diverse thioesters and amides, thereby enhancing the synthetic potential of carboxylic acid derivatives. This work presents a photochemical strategy for thioester and amide synthesis that employs thiobenzoic S‐acids as one‐electron reductants and sulfur‐centred radical precursors, utilizing Bi 2 S 3 nanostructures as the photocatalyst. The Bi 2 S 3 nanostructures were prepared through a solvothermal method employing a choline chloride/thiourea deep eutectic solvent, which plays a multifaceted role as the solvent, soft template, and in situ sulfur source. These nanostructures were subsequently employed in visible light‐induced thioesterification, enabling oxidative radical coupling of aromatic and aliphatic thioic acids with thiols under visible light. Mechanistic investigations, including TEMPO‐based radical trapping experiments, confirm the involvement of free radical intermediates. Additional control experiments were conducted to elucidate the reaction mechanism and define the catalytic pathway. This protocol offers several advantages, including excellent catalytic efficiency, broad substrate applicability, high selectivity, good functional group tolerance, and catalyst recyclability, establishing it as a sustainable and practical one‐pot route for thioesterification and amidation reactions.

Failure analysis of a P11 steel reheater header: Transgranular stress corrosion cracking induced by chromium depletion, tri-layered oxidation, and multi-stress coupling

Deciphering the galantamine biosynthetic pathway in Lycoris species lays the foundation for plant chassis-based production.

Oxidative coupling of methane (OCM) over Ce-loaded CaO catalysts: Investigating the active sites

Two microporous metal–organic frameworks incorporating an anthracene–containing ligand, 2,6–bis[2–(4–pyridyl)ethenyl]anthracene, were synthesized using different linear dicarboxylates: terephthalic acid (complex 1) and 4–(2–carboxyvinyl)benzoic acid (complex 2). The choice of dicarboxylic acid directs distinct secondary building units (SBU) and topologies: complex 1 features a mononuclear tetrahedral SBU and a three–dimensional (3D) network, whereas complex 2 adopts a dinuclear paddle–wheel SBU with a classic pillar–layer architecture. These structural differences lead to divergent photocatalytic behavior in the oxidative coupling of amines, with complex 1 delivering superior conversion and product selectivity compared to the less efficient complex 2.

Achieving productive aerobic oxidation of alcohols in the presence of more easily oxidized partners is a central challenge in photocatalytic synthesis. In particular, visible-light-driven routes from abundant primary alcohols to benzimidazoles are hampered by the inertness of linear aliphatic alcohols and the oxidative fragility of o-phenylenediamines (OPDs), which has forced previous methods to use the alcohol as the bulk solvent. Here we show that halide-tuned CsPbX3 (X = Cl/Br/I) perovskite nanocrystals act as adsorption-biased, band-engineered photocatalysts for this transformation. By adjusting the halide composition, we prepare a toolbox of photocatalysts whose excited-state oxidation potentials are matched to different classes of primary alcohols: CsPbCl3 under 405 nm irradiation efficiently oxidizes linear aliphatic alcohols, whereas CsPbClBr2 under 455 nm light is optimal for benzylic alcohols. For challenging linear aliphatic alcohols, this oxidative dehydrogenative coupling operates with only ∼3 equiv of the alcohol (rather than solvent-level quantities), while benzylic alcohols are converted with only 2 equiv, in all cases using O2 (1 atm) as the terminal oxidant under mild, noble-metal-free and heterogeneous conditions to furnish a broad range of 2-alkyl and 2-aryl benzimidazoles. Temperature-programmed desorption experiments and density functional theory (DFT) calculations indicate that primary alcohols bind much more strongly to the perovskite surface than OPDs, while photophysical and electrochemical studies map a two-step interfacial electron-transfer sequence: alcohol → perovskite(h+) → O2. Together, these results demonstrate an adsorption-biased, halide-tunable perovskite platform for alcohol-favored aerobic oxidation and suggest a general design strategy for heterogeneous photoredox synthesis.