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Acetic acid (AA), a vital compound in chemical production and materials manufacturing, is conventionally synthesized by starting with coal or methane through multiple steps including high‐temperature transformations. Here we present a new synthesis of AA from ethane through photocatalytic selective oxidation of ethane by H2O2 at 0–25 °C. The catalyst designed for this process comprises g‐C3N4 with anchored Pd1 single‐atom sites. In situ studies and computational simulation suggest the immobilized Pd1 atom becomes positively charged under photocatalytic condition. Under photoirradiation, the holes on the Pd1 single‐atom of OH−Pd1⊕ ${{}^{\oplus }}$ /g‐C3N4 serves as a catalytic site for activating a C−H instead of C−C of C2H6 with a low activation barrier of 0.14 eV, through a concerted mechanism. Remarkably, the selectivity for synthesizing AA reaches 98.7 %, achieved under atmospheric pressure of ethane at 0 °C. By integrating photocatalysis with thermal catalysis, we introduce a highly selective, environmentally friendly, energy‐efficient synthetic route for AA, starting from ethane, presenting a promising alternative for AA synthesis. This integration of photocatalysis in low‐temperature oxidation demonstrates a new route of selective oxidation of light alkanes. [ABSTRACT FROM AUTHOR]

Oxygen vacancies (OV) in nonmetallic plasmonic photocatalysts can decrease the energy barrier for CO2 reduction, boosting C1 intermediate production for potential C2 formation. However, their susceptibility to oxidation weakens C1 intermediate adsorption. Herein we proposed a "photoelectron injection" strategy to safeguard OV in W18O49 by creating a W18O49/ZIS (W/Z) plasmonic photocatalyst. Moreover, photoelectrons contribute to the local multi‐electron environment of W18O49, enhancing the intrinsic excitation of its hot electrons with extended lifetimes, as confirmed by in situ XPS and femtosecond transient absorption analysis. Density functional theory calculations revealed that W/Z with OV enhances CO2 adsorption, activating *CO production, while reducing the energy barrier for *COH production (0.054 eV) and subsequent *CO−*COH coupling (0.574 eV). Successive hydrogenation revealed that the free energy for *CH2CH2 hydrogenation (0.108 eV) was lower than that for *CH2CH2 desorption for C2H4 production (0.277 eV), favouring C2H6 production. Consequently, W/Z achieves an efficient C2H6 activity of 653.6 μmol g−1 h−1 under visible light, with an exceptionally high selectivity of 90.6 %. This work offers a new strategy for the rational design of plasmonic photocatalysts with high selectivity for C2+ products. [ABSTRACT FROM AUTHOR]

The urgency to mitigate environmental impacts from anthropogenic CO2 emissions has propelled extensive research efforts on CO2 reduction. The current work reports a novel approach involving transforming CO2 and ethane into carbon nanotubes (CNTs) using earth‐abundant metals (Fe, Co, Ni) at 750 °C. This route facilitates long‐term carbon storage via generating high‐value CNTs and produces valuable syngas with adjustable H2/CO ratios as byproducts. Without CO2, direct pyrolysis of ethane undergoes rapid deactivation. The participation of CO2 not only enhances the durability of the catalyst, but also contributes about 30 % of the CNTs production, presenting a viable solution to CO2 challenges. The CNT morphology depends on the catalyst used. Co‐ and Ni‐based catalysts produce CNT with a 20 nm diameter and micrometer length, whereas Fe‐based catalysts yield bamboo‐like structures. This work represents a pioneering effort in utilizing CO2 and ethane for CNT production with potential environmental and economic benefits. [ABSTRACT FROM AUTHOR]

C−H dissociation and C−C coupling are two key steps in converting CH4 into multi‐carbon compounds. Here we report a synergy of Au and Ag to greatly promote C2H6 formation over Au1Ag single‐atom alloy nanoparticles (Au1Ag NPs)‐modified ZnO catalyst via photocatalytic oxidative coupling of methane (POCM) with O2 and H2O. Atomically dispersed Au in Au1Ag NPs effectively promotes the dissociation of O2 and H2O into *OOH, promoting C−H activation of CH4 on the photogenerated O− to form *CH3. Electron‐deficient Au single atoms, as hopping ladders, also facilitate the migration of electron donor *CH3 from ZnO to Au1Ag NPs. Finally, *CH3 coupling can readily occur on Ag atoms of Au1Ag NPs. An excellent C2H6 yield of 14.0 mmol g−1 h−1 with a selectivity of 79 % and an apparent quantum yield of 14.6 % at 350 nm is obtained via POCM with O2 and H2O, which is at least two times that of the photocatalytic system. The bimetallic synergistic strategy offers guidance for future catalyst design for POCM with O2 and H2O. [ABSTRACT FROM AUTHOR]

Photo‐driven CH4 conversion to multi‐carbon products and H2 is attractive but challenging, and the development of efficient catalytic systems is critical. Herein, we construct a solar‐energy‐driven redox cycle for combining CH4 conversion and H2 production using iron ions. A photo‐driven iron‐induced reaction system was developed, which is efficient at selective coupling of CH4 as well as conversion of benzene and cyclohexane under mild conditions. For CH4 conversion, 94 % C2 selectivity and a C2H6 formation rate of 8.4 μmol h−1 is achieved. Mechanistic studies reveal that CH4 coupling is induced by hydroxyl radical, which is generated by photo‐driven intermolecular charge migration of an Fe3+ complex. The delicate coordination structure of the [Fe(H2O)5OH]2+ complex ensures selective C−H bond activation and C−C coupling of CH4. The produced Fe2+ can be used to reduce the potential for electrolytic H2 production, and then turns back into Fe3+, forming an energy‐saving and sustainable recyclable system. [ABSTRACT FROM AUTHOR]

Adsorptive separation is an energy‐efficient alternative, but its advancement has been hindered by the challenge of industrially potential adsorbents development. Herein, a novel ultra‐microporous metal‐organic framework ZU‐901 is designed that satisfies the basic criteria raised by ethylene/ethane (C2H4/C2H6) pressure swing adsorption (PSA). ZU‐901 exhibits an "S" shaped C2H4 curve with high sorbent selection parameter (65) and could be mildly regenerated. Through green aqueous‐phase synthesis, ZU‐901 is easily scalable with 99 % yield, and it is stable in water, acid, basic solutions and cycling breakthrough experiments. Polymer‐grade C2H4 (99.51 %) could be obtained via a simulating two‐bed PSA process, and the corresponding energy consumption is only 1/10 of that of simulating cryogenic distillation. Our work has demonstrated the great potential of pore engineering in designing porous materials with desired adsorption and desorption behavior to implement an efficient PSA process. [ABSTRACT FROM AUTHOR]

Two C2H6‐selective metal‐organic framework (MOF) adsorbents with ultrahigh stability, high surface areas, and suitable pore size have been designed and synthesized for one‐step separation of ethane/ethylene (C2H6/C2H4) under humid conditions to produce polymer‐grade pure C2H4. Experimental results reveal that these two MOFs not only adsorb a high amount of C2H6 but also display good C2H6/C2H4 selectivity verified by fixed bed column breakthrough experiments. Most importantly, the good water stability and hydrophobic pore environments make these two MOFs capable of efficiently separating C2H6/C2H4 under humid conditions, exhibiting the benchmark performance among all reported adsorbents for separation of C2H6/C2H4 under humid conditions. Moreover, the affinity sites and their static adsorption energies were successfully revealed by single crystal data and computation studies. Adsorbents described in this work can be used to address major chemical industrial challenges. [ABSTRACT FROM AUTHOR]

Oxidative dehydrogenation of ethane to ethylene is an important process in light olefin industry; however, the over‐oxidation of ethane leads to low ethylene selectivity. Here, we report a novel approach to electrochemical oxidative dehydrogenation of ethane in anode in conjunction with CO2 reduction at cathode in a solid oxide electrolyser using a porous single‐crystalline CeO2 electrode at 600 °C. We identify and engineer the flux and chemical states of active oxygen species that evolve from the lattice at anode surface to activate and dehydrogenate ethane to ethylene via the reaction of epoxy species. Active oxygen species (O2−, O22− and O2−) at the anode surface effectively dehydrogenate ethane to ethylene, but O− species tend to induce deep oxidation. We demonstrate exceptionally high ethylene selectivity of 95 % and an ethane conversion of 10 % with a durable operation of 300 h. [ABSTRACT FROM AUTHOR]

Oxidative dehydrogenation of ethane (ODE) is limited by the facile deep oxidation and potential safety hazards. Now, electrochemical ODE reaction is incorporated into the anode of a solid oxide electrolysis cell, utilizing the oxygen species generated at anode to catalytically convert ethane. By infiltrating γ‐Al2O3 onto the surface of La0.6Sr0.4Co0.2Fe0.8O3‐δ‐Sm0.2Ce0.8O2‐δ (LSCF‐SDC) anode, the ethylene selectivity reaches as high as 92.5 %, while the highest ethane conversion is up to 29.1 % at 600 °C with optimized current and ethane flow rate. Density functional theory calculations and in situ X‐ray photoelectron spectroscopy characterizations reveal that the Al2O3/LSCF interfaces effectively reduce the amount of adsorbed oxygen species, leading to improved ethylene selectivity and stability, and that the formation of Al‐O‐Fe alters the electronic structure of interfacial Fe center with increased density of state around Fermi level and downshift of the empty band, which enhances ethane adsorption and conversion. [ABSTRACT FROM AUTHOR]

Purification of C2H4 from an C2H4/C2H6 mixture, one of the most important while challenging industrial separation processes, is mainly through energy‐intensive cryogenic distillation. Now a family of gallate‐based metal–organic framework (MOF) materials is presented, M‐gallate (M=Ni, Mg, Co), featuring 3D interconnected zigzag channels, the aperture sizes of which (3.47–3.69 Å) are ideally suitable for molecular sieving of ethylene (3.28×4.18×4.84 Å3) and ethane (3.81×4.08×4.82 Å3) through molecular cross‐section size differentiation. Co‐gallate shows an unprecedented IAST selectivity of 52 for C2H4 over C2H6 with a C2H4 uptake of 3.37 mmol g−1 at 298 K and 1 bar, outperforming the state‐of‐the‐art MOF material NOTT‐300. Direct breakthrough experiments with equimolar C2H4/C2H6 mixtures confirmed that M‐gallate is highly selective for ethylene. The adsorption structure and mechanism of ethylene in the M‐gallate was further studied through neutron diffraction experiments. Purification of C2H4 from an C2H4/C2H6 mixture using a family of gallate‐based metal–organic framework (MOF) materials is presented. M‐gallate (M=Ni, Mg, Co), features 3D interconnected zigzag channels, the aperture sizes of which are ideal for molecular sieving of ethylene and ethane through molecular cross‐section size differentiation. [ABSTRACT FROM AUTHOR]

The recent shale gas boom combined with the requirement to reduce atmospheric CO2 have created an opportunity for using both raw materials (shale gas and CO2) in a single process. Shale gas is primarily made up of methane, but ethane comprises about 10% and reserves are underutilized. Two routes have been investigated by combining ethane decomposition with CO2 reduction to produce products of higher value. The first reaction is ethane dry reforming which produces synthesis gas (CO+H2). The second route is oxidative dehydrogenation which produces ethylene using CO2 as a soft oxidant. The results of this study indicate that the Pt/ CeO2 catalyst shows promise for the production of synthesis gas, while Mo2C-based materials preserve the C-C bond of ethane to produce ethylene. These findings are supported by density functional theory (DFT) calculations and X-ray absorption near-edge spectroscopy (XANES) characterization of the catalysts under in situ reaction conditions. [ABSTRACT FROM AUTHOR]