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In this paper, CaxZn10‐xFe20 catalysts were prepared by the co‐precipitation method and applied to CO2 hydrogenation. The experimental results show that the CO2 conversion of the catalyst Ca1Zn9Fe20 at a Ca doping amount of 1 mmol can reach 57.91 %, which is 13.5 % more than the CO2 conversion of the catalyst Zn10Fe20. Moreover, the catalyst Ca1Zn9Fe20 has the lowest selectivity for both CO and CH4, with 7.40 % and 6.99 %, respectively. The catalysts were characterized by XRD, N2 adsorption‐desorption, CO2‐TPD, H2‐TPR, and XPS. The results demonstrate that the doping of Ca increases the basic sites on the catalyst surface and thus allows the catalyst to adsorb more CO2 to promote the reaction. Besides, the Ca doping amount of 1 mmol can suppress the formation of graphitic carbon on the catalyst surface and prevent the excess graphitic carbon from covering the active site Fe5C2. [ABSTRACT FROM AUTHOR]

Regulating the coordination environment via heteroatoms to break the symmetrical electronic structure of M‐N4 active sites provides a promising route to engineer metal‐nitrogen‐carbon catalysts for electrochemical CO2 reduction reaction. However, it remains challenging to realize a site‐specific introduction of heteroatoms at atomic level due to their energetically unstable nature. Here, this paper reports a facile route via using an oxygen‐ and nitrogen‐rich metal–organic framework (MOF) (IRMOF‐3) as the precursor to construct the Fe‐O and Fe‐N chelation, simultaneously, resulting in an atomically dispersed axial O‐coordinated FeN4 active site. Compared to the FeN4 active sites without O coordination, the formed FeN4‐O sites exhibit much better catalytic performance toward CO, reaching a maximum FECO of 95% at −0.50 V versus reversible hydrogen electrode. To the best of the authors' knowledge, such performance exceeds that of the existing Fe‐N‐C‐based catalysts derived from sole N‐rich MOFs. Density functional theory calculations indicate that the axial O‐coordination regulates the binding energy of intermediates in the reaction pathways, resulting in a smoother desorption of CO and increased energy for the competitive hydrogen production. [ABSTRACT FROM AUTHOR]

The methanol oxidation reaction has high energy density and the product is non‐toxic and harmless (CO2, H2O), making it become one of the targets of new fuel energy. To maximize the efficiency of the reaction, its key lies in the development of highly efficient catalysts. In this paper, we reviewed the types of methanol electrocatalytic oxidation catalysts in recent years, some new preparation methods, and the reaction mechanism of different types of catalyst systems, and discussed their structure‐activity relationships, laying the foundation for the development of highly efficient new catalysts in the future. And this paper is included on the types of catalysts (Pt‐based catalyst, Ni‐based catalyst, and other transition metal‐based catalyst) and preparation methods (Reduction method, sol‐gel method, in‐situ method), and discussed the catalytic mechanism which mainly starts from two aspects, one is adsorption‐desorption, the other is the bond between the catalyst, methanol, and the medium. Finally, the future challenges and opportunities of the electrocatalytic oxidation of methanol are discussed. [ABSTRACT FROM AUTHOR]

Hard‐ and softwood residues (from birch and pine respectively) of forestry, pulp, and paper industries (e. g. sawdust, branches) were used to prepare biochar, which was then oxidized using nitric acid to produce catalytic carboxylic acid functionalized biochar. This oxidized biochar, ox–bc, in the presence of a co‐catalyst, showed excellent catalytic activity towards the cycloaddition reaction between CO2 and epoxides using mild conditions (CO2 pressure, 10 bar). No differences in catalytic activity were seen between the two types of oxidized biochar despite the hardwood ox–bc having a significantly higher surface area. The catalysts function through activation of the epoxide reagent via hydrogen‐bonding with carboxylic acid groups on the surface. The number of surface acid groups was reduced by reaction with 3‐aminopropyltriethoxysilane and the resulting material was inactive in the reactions studied. The ox–bc catalysts are sustainable, economic, and renewable alternatives for currently used heterogeneous systems and are also the first carbon‐based materials derived from biomass to exhibit good recyclability (over five runs) with a broad substrate scope for the production of cyclic carbonates from epoxides and CO2. [ABSTRACT FROM AUTHOR]

Abstract: Carbon dioxide (CO2) reduction in aqueous solutions is an attractive strategy for carbon capture and utilization. Cuprous oxide (Cu2O) is a promising catalyst for CO2 reduction as it can convert CO2 into valuable hydrocarbons and suppress the side hydrogen evolution reaction (HER). However, the nature of the active sites in Cu2O remains under debate because of the complex surface structure of Cu2O under reducing conditions, leading to limited guidance in designing improved Cu2O catalysts. This paper describes the functionality of surface‐bonded hydroxy groups on partially reduced Cu2O(111) for the CO2 reduction reaction (CO2RR) by combined density functional theory (DFT) calculations and experimental studies. We find that the surface hydroxy groups play a crucial role in the CO2RR and HER, and a moderate coverage of hydroxy groups is optimal for promotion of the CO2RR and suppression of the HER simultaneously. Electronic structure analysis indicates that the charge transfer from hydroxy groups to coordination‐unsaturated Cu (CuCUS) sites stabilizes surface‐adsorbed COOH*, which is a key intermediate during the CO2RR. Moreover, the CO2RR was evaluated over Cu2O octahedral catalysts with {111} facets and different surface coverages of hydroxy groups, which demonstrates that Cu2O octahedra with moderate coverage of hydroxy groups can indeed enhance the CO2RR and suppress the HER. [ABSTRACT FROM AUTHOR]

The Front Cover shows an amino‐modified copper(I) oxide catalyst reduces the Gibbs free energy for electrocatalytic reduction of carbon dioxide to ethylene. The roller coasters and tracks represent the catalysts and the Gibbs free energy, respectively. In their Full Paper, H. Deng et al, illustrate that the modification of amino on copper(I) oxide promotes the hydrogenation of *CO to *CHO, which is the rate‐determining step for the formation of ethylene. This work presents an amino‐assisted carbon‐carbon coupling mechanism during electroreduction of carbon dioxide to multi‐carbon products. More information can be found in the Full Paper by H. Deng et al. [ABSTRACT FROM AUTHOR]

Keywords: carbon dioxide; hydrogenation; Cu-based catalyst; hydrogen enrichment; ethylene carbonate EN carbon dioxide hydrogenation Cu-based catalyst hydrogen enrichment ethylene carbonate 3599 3599 1 07/23/20 20200721 NES 200721 The Cover Feature shows a nanoflower-like Cu/SiO SB 2 sb catalyst of H SB 2 sb -enrichment capacity used for the hydrogenation of ethylene carbonate (EC) derived from CO SB 2 sb to produce methanol and ethylene glycol. In their Full Paper, M. Zhang, Y. Yang et al. synthesized the nanoflower-like copper catalysts with open-ended fibers and well-dispersed active species via one-step hydrolysis precipitation method. Carbon dioxide, hydrogenation, Cu-based catalyst, hydrogen enrichment, ethylene carbonate. [Extracted from the article]

Catalytic hydrogenation of carbon dioxide to methane can not only achieve the recycling of carbon resources, but also effectively meet the increasing demand for natural gas. In this paper, Ni‐based catalysts on different supports including ZrO2, CeO2 and Al2O3 were synthesized using citric acid complexation method and their CO2 methanation performances were tested. Among these catalysts, the Ni/ZrO2 catalyst achieved the best CO2 methanation activity. The catalysts were characterized by N2‐physisorption, XRD, H2‐TPR and H2‐TPD. The results indicate that the superiority of the Ni/ZrO2 catalyst can be mainly ascribed to its not only high Ni dispersion but also high reduction degree. Since the reduction degree of Ni/Al2O3 is low, it exhibits poor activity. The preparation condition for the Ni/ZrO2 catalyst was further optimized. The result shows that at molar ratio of citric acid to Ni ions of 3, the catalyst exhibits the best activity owing to the highest Ni dispersion, the largest Ni surface area, an appropriate metal‐support interaction and the most moderate basic sites. [ABSTRACT FROM AUTHOR]

The Front Cover shows the production of formic acid from CO2 and H2 by a ternary hybrid catalyst composed of an Ir complex, poly(ethyleneimine) and titanate nanotubes (TNTs).In their Full Paper, Y. Kuwahara et al. demonstrate that immobilization of a poly(ethyleneimine)‐tethered Ir complex catalyst inside the cavity space of TNTs can afford efficient catalysts with both improved activity and reusability, owing to the CO2 adsorption capacity of poly(ethyleneimine) and stabilizing effect of TNTs. This study can potentially offer a generalized method to capture and convert CO2, which is particularly desirable for sustainable formic acid production. More information can be found in the Full Paper by Y. Kuwahara et al. on page 1906 in Issue 11, 2017 (DOI: 10.1002/cctc.201700508). [ABSTRACT FROM AUTHOR]

The front cover artwork for Issue 10/2019 is a collaboration between the O'Hair group (University of Melbourne, Australia) and the Bonačić‐Koutecký group (University of Split, Croatia). The image shows how gas‐phase studies of model systems can be used for the design of MOF based catalysts for the selective decomposition of formic acid into hydrogen and carbon dioxide, a reaction of considerable interest for hydrogen storage applications. See the Full Paper itself at https://doi.org/10.1002/cctc.201900346. [ABSTRACT FROM AUTHOR]

The front cover artwork for Issue 18/2017 is provided by the Fritz-Haber-Institut der Max-Planck-Gesellschaft, Department of Inorganic Chemistry, Berlin (Germany). The image shows the proposed network of consecutive and parallel reactions in oxidation of propane over vanadium oxide catalysts. Detailed understanding of the complex system is necessary to advance catalyst and process design in terms of high selectivity to desired olefins and oxygenates, prevention of CO2 formation, and sustainable use of resources. See the Full Paper itself at . [ABSTRACT FROM AUTHOR]