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The synergy between metals and metal oxides can effectively improve the heterogeneous catalytic process. This paper describes the intrinsic effect of Pt modification over GaOx (Pt−GaOx) on propane dehydrogenation. The presence of Pt promotes H2 dissociation and surface coverage of hydrogen species, which is beneficial for the activation of C−H in propane. With excessive Pt, Gaδ+ can be further reduced to form Pt−Ga alloy with less surface hydrogen species. Consequently, the relative propylene formation rate between Pt−GaOx and the summed contribution of individual Pt and GaOx increases linearly with the content of hydrogen species. Optimally, the relative propylene formation rate of Pt−GaOx with 0.03 wt % Pt exceeds 25 % of the summed contribution of individual components. [ABSTRACT FROM AUTHOR]

Cobalt‐copper (CoCu) catalysts have industrial potential in CO/CO2 hydrogenation reactions, and CoCu alloy has been elucidated as a major active phase during reactions. However, due to elemental surface segregation and dealloying phenomena, the actual surface morphology of CoCu alloy is still unclear. Combining theory and experiment, the dual effect of surface segregation and varied CO coverage over the CoCu(111) surface on the reactivity in CO2 hydrogenation reactions is explored. The relationship between C−O bond scission and further hydrogenation of intermediate *CH2O was discovered to be a key step to promote ethanol production. The theoretical investigation suggests that moderate Co segregation provides a suitable surface Co ensemble with lateral interactions of co‐adsorbed *CO, leading to promoted selectivity to ethanol, in agreement with theory‐inspired experiments. [ABSTRACT FROM AUTHOR]

Cu‐based electrocatalysts facilitate CO2 electrochemical reduction (CO2ER) to produce multi‐carbon products. However, the roles of Cu0 and Cu+ and the mechanistic understanding remain elusive. This paper describes the controllable construction of Cu0‐Cu+ sites derived from the well‐dispersed cupric oxide particles supported on copper phyllosilicate lamella to enhance CO2ER performance. 20 % Cu/CuSiO3 shows the superior CO2ER performance with 51.8 % C2H4 Faraday efficiency at −1.1 V vs reversible hydrogen electrode during the 6 hour test. In situ attenuated total reflection infrared spectra and density functional theory (DFT) calculations were employed to elucidate the reaction mechanism. The enhancement in CO2ER activity is mainly attributed to the synergism of Cu0‐Cu+ pairs: Cu0 activates CO2 and facilitates the following electron transfers; Cu+ strengthens *CO adsorption to further boost C−C coupling. We provide a strategy to rationally design Cu‐based catalysts with viable valence states to boost CO2ER. [ABSTRACT FROM AUTHOR]

Silicon is a promising photocathode material in photoelectrochemical water splitting for hydrogen production, but it is primarily limited by photocorrosion in aqueous electrolytes. As an extensively used protective material, crystalline TiO2 could protect Si photoelectrode against corrosion. However, a large number of grain boundaries (GBs) in polycrystalline TiO2 would induce excessive recombination centers, impeding the carrier transport. This paper describes the introduction of oxygen vacancies (Ovac) with controllable spatial distribution for GBs to promote carrier transport. Two kinds of Ovac distribution, Ovac along GBs and Ovac inside grains, are compared, where the latter one is demonstrated to facilitate carrier transport owing to the formation of tunneling paths across GBs. Consequently, a simple p‐Si/TiO2/Pt heterojunction photocathode with controllable Ovac distribution in TiO2 shows a +400 mV onset potential shift and yields an applied bias photon‐to‐current efficiency of 5.9 %, which is the best efficiency reported among silicon photocathodes except for silicon homojunction. [ABSTRACT FROM AUTHOR]

It is of great significance to reveal the detailed mechanism of neighboring effects between monomers, as they could not only affect the intermediate bonding but also change the reaction pathway. This paper describes the electronic effect between neighboring Zn/Co monomers effectively promoting CO2 electroreduction to CO. Zn and Co atoms coordinated on N doped carbon (ZnCoNC) show a CO faradaic efficiency of 93.2 % at −0.5 V versus RHE during a 30‐hours test. Extended X‐ray absorption fine structure measurements (EXAFS) indicated no direct metal–metal bonding and X‐ray absorption near‐edge structure (XANES) showed the electronic effect between Zn/Co monomers. In situ attenuated total reflection‐infrared spectroscopy (ATR‐IR) and density functional theory (DFT) calculations further revealed that the electronic effect between Zn/Co enhanced the *COOH intermediate bonding on Zn sites and thus promoted CO production. This work could act as a promising way to reveal the mechanism of neighboring monomers and to influence catalysis. [ABSTRACT FROM AUTHOR]

The photocatalytic CO2 reduction reaction (CRR) represents a promising route for the clean utilization of stranded renewable resources, but poor selectivity resulting from the competing hydrogen evolution reaction (HER) in aqueous solution limits its practical applicability. In the present contribution a photocatalyst with hydrophobic surfaces was fabricated. It facilitates an efficient three‐phase contact of CO2 (gas), H2O (liquid), and catalyst (solid). Thus, concentrated CO2 molecules in the gas phase contact the catalyst surface directly, and can overcome the mass‐transfer limitations of CO2, inhibit the HER because of lowering proton contacts, and overall enhance the CRR. Even when loaded with platinum nanoparticles, one of the most efficient HER promotion cocatalysts, the three‐phase photocatalyst maintains a selectivity of 87.9 %. Overall, three‐phase photocatalysis provides a general and reliable method to enhance the competitiveness of the CRR. [ABSTRACT FROM AUTHOR]

Identification of the active structure under reaction conditions is of great importance for the rational design of heterogeneous catalysts. However, this is often hampered by their structural complexity. The interplay between the surface structure of Co3O4 and the CO2 hydrogenation is described. Co3O4 with morphology‐dependent crystallographic surfaces presents different reducibility and formation energy of oxygen vacancies, thus resulting in distinct steady‐state composition and product selectivity. Co3O4‐0 h rhombic dodecahedra were completely reduced to Co0 and CoO, which presents circa 85 % CH4 selectivity. In contrast, Co3O4‐2 h nanorods were partially reduced to CoO, which exhibits a circa 95 % CO selectivity. The crucial role of the Co3O4 structure in determining the catalytic performance for higher alcohol synthesis over CuCo‐based catalysts is demonstrated. As expected, Cu/Co3O4‐2 h shows nine‐fold higher ethanol yield than Cu/Co3O4‐0 h owing to the inhibition for methanation. [ABSTRACT FROM AUTHOR]

The production of CH3OH from the photocatalytic CO2 reduction reaction (PCRR) presents a promising route for the clean utilization of renewable resources, but charge recombination, an unsatisfying stability and a poor selectivity limit its practical application. In this paper, we present the design and fabrication of 0D/2D materials with polymeric C3N4 nanosheets and CdSe quantum dots (QDs) to enhance the separation and reduce the diffusion length of charge carriers. The rapid outflow of carriers also restrains self‐corrosion and consequently enhances the stability. Furthermore, based on quantum confinement effects of the QDs, the energy of the electrons could be adjusted to a level that inhibits the hydrogen evolution reaction (HER, the main competitive reaction to PCRR) and improves the selectivity and activity for CH3OH production from the PCRR. The band structures of photocatalysts with various CdSe particle sizes were also investigated quantitatively to establish the relationship between the band energy and the photocatalytic performance. Reduced to the max: A strategy for selective photocatalytic CO2 reduction in aqueous solution based on the adjustment of the reduction potential of electrons in CdSe quantum dots is presented. The approach also inhibits the competitive hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

Artificial photosynthesis can be used to store solar energy and reduce CO2 into fuels to potentially alleviate global warming and the energy crisis. Compared to the generation of gaseous products, it remains a great challenge to tune the product distribution of artificial photosynthesis to liquid fuels, such as CH3OH, which are suitable for storage and transport. Herein, we describe the introduction of metallic Cu nanoparticles (NPs) on Cu2O films to change the product distribution from gaseous products on bare Cu2O to predominantly CH3OH by CO2 reduction in aqueous solutions. The specifically designed Cu/Cu2O interfaces balance the binding strengths of H* and CO* intermediates, which play critical roles in CH3OH production. With a TiO2 model photoanode to construct a photoelectrochemical cell, a Cu/Cu2O dark cathode exhibited a Faradaic efficiency of up to 53.6 % for CH3OH production. This work demonstrates the feasibility and mechanism of interface engineering to enhance the CH3OH production from CO2 reduction in aqueous electrolytes. Metallic copper nanoparticles were deposited on Cu2O films to change the product distribution of CO2 reduction in aqueous solution from the gaseous products generated on bare Cu2O to predominantly methanol. The carefully designed Cu/Cu2O interfaces balance the binding strengths of the H* and CO* intermediates, which enables efficient methanol production. [ABSTRACT FROM AUTHOR]

Abstract: Supported vanadium oxides are one of the most promising alternative catalysts for propane dehydrogenation (PDH) and efforts have been made to improve its catalytic performance. However, unlike Pt‐based catalysts, the nature of the active site and surface structure of the supported vanadium catalysts under reductive reaction conditions still remain elusive. This paper describes the surface structure and the important role of surface‐bound hydroxyl groups on VOx / γ‐Al2O3 catalysts under reaction conditions employing in situ DRIFTS experiments and DFT calculations. It is shown that hydroxyl groups on the VOx /Al2O3 catalyst (V−OH) are produced under H2 pre‐reduction, and the catalytic performance for PDH is closely connected to the concentration of V−OH species on the catalyst. The hydroxyl groups are found to improve the catalyst that leads to better stability by suppressing the coke deposition. [ABSTRACT FROM AUTHOR]

Abstract: A hundred years on, the energy‐intensive Haber–Bosch process continues to turn the N2 in air into fertilizer, nourishing billions of people while causing pollution and greenhouse gas emissions. The urgency of mitigating climate change motivates society to progress toward a more sustainable method for fixing N2 that is based on clean energy. Surface oxygen vacancies (surface Ovac) hold great potential for N2 adsorption and activation, but introducing Ovac on the very surface without affecting bulk properties remains a great challenge. Fine tuning of the surface Ovac by atomic layer deposition is described, forming a thin amorphous TiO2 layer on plasmon‐enhanced rutile TiO2/Au nanorods. Surface Ovac in the outer amorphous TiO2 thin layer promote the adsorption and activation of N2, which facilitates N2 reduction to ammonia by excited electrons from ultraviolet‐light‐driven TiO2 and visible‐light‐driven Au surface plasmons. The findings offer a new approach to N2 photofixation under ambient conditions (that is, room temperature and atmospheric pressure). [ABSTRACT FROM AUTHOR]