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CO2 conversion to CH3OH under mild conditions is of particular interest yet rather challenging. Both electro- and thermo-catalytic CO2 reduction to CH3OH can only produce CH3OH in low concentration (typically mixed with water), requiring energy-intensive purification processes. Here we design a sun-simulated-driven tandem catalytic system comprising CO2 electroreduction to syngas, and further photothermal conversion into high-purity CH3OH (volume fraction > 97%). We construct a self-supporting electrocatalyst featuring dual active sites of Ni single atoms and encapsulated Co nanoparticles, which could produce syngas with a constant H2:CO ratio of ~2 via solar-powered CO2 electroreduction. The generated syngas is subsequently fed into the photothermal module, which could produce high-purity CH3OH under 1 sun-light irradiation, with a rate of 0.238 gCH3OH gcat–1 h–1. This work demonstrates a feasible and sustainable route for directly converting CO2 into high-purity CH3OH. CO2 conversion to CH3OH under mild conditions is of particular interest yet rather challenging. Here, the authors report a sun-simulated-driven tandem catalytic system comprising CO2 electroreduction to syngas, and further photothermal conversion into high-purity CH3OH (volume fraction <97%). [ABSTRACT FROM AUTHOR]

Transition-metal layered double hydroxides are widely utilized as electrocatalysts for the oxygen evolution reaction (OER), undergoing dynamic transformation into active oxyhydroxides during electrochemical operation. Nonetheless, our understanding of the non-equilibrium structural changes that occur during this process remains limited. In this study, utilizing in situ energy-dispersive X-ray absorption spectroscopy and machine learning analysis, we reveal the occurrence of deprotonation and elucidate the role of incorporated iron in facilitating the transition from nickel-iron layered double hydroxide (NiFe LDH) into its active oxyhydroxide. Our findings demonstrate that iron substitution promotes deprotonation process within NiFe LDH, resulting in the preferential removal of protons from the specific bridged hydroxyl group (Ni2+-OH-Fe3+) linked to edge-sharing [NiO6] and [FeO6] octahedron. This deprotonation behavior drives the formation of high-valence Ni3+δ species (0 <δ < 1), which subsequently serve as the active sites, thereby ensuring efficient oxygen evolution activity. This approach offers high-resolution insights of dynamic structural evolution, overcoming the limitations of extended acquisition times and advancing our understanding of OER mechanisms. Real-time monitoring of the structural evolution of catalysts is essential for uncovering catalytic mechanisms and enhancing performance. Here, the authors report a time-resolved measurement that reveals the reconstruction of NiFe-based (oxy)hydroxides, facilitating highly active oxygen evolution. [ABSTRACT FROM AUTHOR]

Rational design of efficient methanol oxidation reaction (MOR) catalyst that undergo non‐CO pathway is essential to resolve the long‐standing poisoning issue. However, it remains a huge challenge due to the rather difficulty in maximizing the non‐CO pathway by the selective coupling between the key *CHO and *OH intermediates. Here, we report a high‐performance electrocatalyst of patchy atomic‐layer Pt epitaxial growth on CeO2 nanocube (Pt ALs/CeO2) with maximum electronic metal‐support interaction for enhancing the coupling selectively. The small‐size monolayer material achieves an optimal geometrical distance between edge Pt−O−Ce sites and *OH absorbed on CeO2, which well restrains the dehydrogenation of *CHO, resulting in the non‐CO pathway. Meanwhile, the *CHO/*CO intermediate generated at inner Pt−O−Ce sites can migrate to edge, inducing the subsequent coupling reaction, thus avoiding poisoning while promoting reaction efficiency. Consequently, Pt ALs/CeO2 exhibits exceptionally catalytic stability with negligible degradation even under 1000 s pure CO poisoning operation and high mass activity (14.87 A/mgPt), enabling it one of the best‐performing alkali‐stable MOR catalysts. [ABSTRACT FROM AUTHOR]

Determining the atomic structure of clusters has been a long-term challenge in theoretical calculations due to the high computational cost of density-functional theory (DFT). Deep learning potential (DP), as an alternative way, has been demonstrated to be able to conduct cluster simulations with close-to DFT accuracy but at a much lower computational cost. In this work, we update 34 structures of the 41 Cu clusters with atomic numbers ranging from 10 to 50 by combining global optimization and the DP model. The calculations show that the configuration of small Cun clusters (n = 10–15) tends to be oblate and it gradually transforms into a cage-like configuration as the size increases (n > 15). Based on the updated structures, their relative stability and electronic properties are extensively studied. In addition, we select three different clusters (Cu13, Cu38, and Cu49) to study their electrocatalytic ability of CO2 reduction. The simulation indicates that the main product is CO for these three clusters, while the selectivity of hydrocarbons is inhibited. This work is expected to clarify the ground-state structures and fundamental properties of Cun clusters, and to guide experiments for the design of Cu-based catalysts. [ABSTRACT FROM AUTHOR]

Author(s): Lina Cao [sup.1] [sup.3] , Wei Liu [sup.2] , Qiquan Luo [sup.1] [sup.3] , Ruoting Yin [sup.1] [sup.3] , Bing Wang [sup.1] [sup.3] , Jonas Weissenrieder [sup.4] , Markus [...], Proton-exchange-membrane fuel cells (PEMFCs) are attractive next-generation power sources for use in vehicles and other applications.sup.1, with development efforts focusing on improving the catalyst system of the fuel cell. One problem is catalyst poisoning by impurity gases such as carbon monoxide (CO), which typically comprises about one per cent of hydrogen fuel.sup.2-4. A possible solution is on-board hydrogen purification, which involves preferential oxidation of CO in hydrogen (PROX).sup.3-7. However, this approach is challenging.sup.8-15 because the catalyst needs to be active and selective towards CO oxidation over a broad range of low temperatures so that CO is efficiently removed (to below 50 parts per million) during continuous PEMFC operation (at about 353 kelvin) and, in the case of automotive fuel cells, during frequent cold-start periods. Here we show that atomically dispersed iron hydroxide, selectively deposited on silica-supported platinum (Pt) nanoparticles, enables complete and 100 per cent selective CO removal through the PROX reaction over the broad temperature range of 198 to 380 kelvin. We find that the mass-specific activity of this system is about 30 times higher than that of more conventional catalysts consisting of Pt on iron oxide supports. In situ X-ray absorption fine-structure measurements reveal that most of the iron hydroxide exists as Fe.sub.1(OH).sub.x clusters anchored on the Pt nanoparticles, with density functional theory calculations indicating that Fe.sub.1(OH).sub.x-Pt single interfacial sites can readily react with CO and facilitate oxygen activation. These findings suggest that in addition to strategies that target oxide-supported precious-metal nanoparticles or isolated metal atoms, the deposition of isolated transition-metal complexes offers new ways of designing highly active metal catalysts.Atomically dispersed iron hydroxide deposited on silica-supported platinum nanoparticles enables complete and selective carbon monoxide removal through preferential oxidation in hydrogen in the temperature range from 198 to 380 kelvin.

Reaction mechanisms of direct conversion of methane to methanol (DCMM) catalyzed by single vacancy graphene supported single Cu atoms (Cu/C3-Gr and Cu/N3-Gr) were investigated using first principles calculations, taking N2O as the oxidant. The catalytic performance was tuned drastically by replacing three coordinated carbon atoms of active center Cu (Cu/C3-Gr) with three nitrogen atoms (Cu/N3-Gr). For Cu/N3-Gr catalyzing DCMM, a crossing between potential energy profiles of the triplet state and the singlet state occurs after transition state of C–H activation. It makes the reaction energy profile downhill and the free energy barrier of C–H activation is only 0.4 eV. The calculation results indicate that Cu/N3-Gr is likely to be an excellent catalyst for DCMM at room temperature, more superior to Cu/C3-Gr. By modulating micro-coordination environment of single atom Cu, both reactivity and selectivity of DCMM were improved remarkably. [ABSTRACT FROM AUTHOR]

Aqueous zinc ion batteries (AZIBs) with high safety, low cost, and eco‐friendliness advantages show great potential in large‐scale energy storage systems. However, their practical application is hindered by low Columbic efficiency and unstable zinc anode resulting from the side reactions and deterioration of zinc dendrites. Herein, tripropylene glycol (TG) is chosen as a dual‐functional organic electrolyte additive to improve the reversibility of AZIBs significantly. Importantly, ab initio molecular dynamics theoretical simulations and experiments such as in situ electrochemical impedance spectroscopy, and synchrotron radiation‐based in situ Fourier transform infrared spectroscopy confirm that TG participates in the solvation sheath of Zn2+, regulating overpotential and inhibiting side reactions; meanwhile, TG inhibits the deterioration of dendrites and modifies the direction of zinc deposition by constructing an adsorbed layer on the zinc anode. Consequently, a Zn‐MnO2 full cell with TG electrolyte exhibited a specific capacity of 124.48 mAh g‐1 after 1000 cycles at a current density of 4 A g‐1. This quantitative regulation for suitable solvation sheath and adsorbed layer on zinc anode, and its easy scalability of the process can be of immediate benefit for the dendrite‐free, high‐performance, and low‐cost energy storage systems. [ABSTRACT FROM AUTHOR]