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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]

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]

Industrial‐scale reforming of methane is typically carried out with an excess of oxidant to suppress coking of the catalyst. On the other hand, many academic studies on dry reforming employ a CO2/CH4 ratio of unity to quickly observe coking which can be reduced by adding a catalyst promoter. In this work, Ni/Al2O3 catalysts were tested for dry reforming of methane (CO2/CH4=1) with additional regeneration steps to test the resistance against an oxidation treatment. Thereby, we wanted to evaluate catalyst stability for industrial relevance. The effects of three promoters, Cr, Mn and Fe, that differ in their degree of CO2 interaction, are compared. A higher iron loading on Ni/Al2O3 leads to higher stability in dry reforming with lower coke formation. However, the higher the concentration of a promoter with high CO2 affinity, the quicker the catalyst is oxidized during regeneration with CO2. Subsequent reduction of a catalyst oxidized with CO2 leads to considerable sintering in all cases. This sintering induces formation of more coke during dry reforming. On such sintered samples only highly effective promoters in large concentrations still have a noticeable effect compared to unpromoted Ni/Al2O3. [ABSTRACT FROM AUTHOR]

The development of effective catalysts for the electrocatalytic carbon dioxide reduction reaction (CO2RR) to two‐carbon (C2) products is a practical approach to solve the energy crisis and stabilize the carbon cycle of the ecosystem. The production of electrocatalytic CO2RR with copper metal shows low selectivity and mainly generates one‐carbon (C1) products, hindering its wide practical application. The use of copper (I) oxide (Cu2O) in electrocatalysis has attracted intense research attention because it can more efficiently produce C2 products with high energy density such as ethylene (C2H4) and ethane (C2H6). We use an amino‐modified Cu2O catalyst (NH2−Cu2O) for electrocatalytic CO2RR to obtain significantly increased production of the CO and C2 products. Electrochemical in‐situ infrared spectroscopy analysis was used to detect the presence of the *COOH and *CHO reaction intermediates. Density functional theory calculations showed that the amino (−NH2) modification reduces the free energy of the *CO→*CHO reaction that is the rate‐determining step in C2H4 production. Our results show that amino modification can promote the protonation of *CO and *CHO carbon‐carbon coupling to produce C2H4. Thus, amino‐modified copper‐based catalysts are promising materials for application in electrocatalytic CO2RR to multi‐carbon products. [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 impact of different co‐catalytically acting promoters (Pt, ZrOx and SmOx) during COx methanation was investigated on alumina supported Co‐based model catalysts. To obtain samples with identical structure and morphology independent of the presence and the type of promoter added, double flame spray pyrolysis was employed for the synthesis, which, in contrast to classical catalyst preparation techniques, allows controlling and separating the particle formation processes of the different catalyst components. In this way, differently promoted and unpromoted catalysts with identical size distributions and dispersions could be synthesized to study co‐catalytic effects in isolation. For CO2 methanation, all promoters led to improved methanation yields and long‐term activities within the whole temperature range as compared to the unpromoted catalyst. Among them, zirconia and platinum performed best. In case of CO methanation, a beneficial influence of the studied promoters could also be verified – with Pt showing the best results. Yet, all catalysts deactivated rapidly above 310 °C, limiting their usability to lower temperatures. [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 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]

Immobilization of well‐defined homogenous (electro)catalysts onto conductive supports offers an attractive strategy for designing advanced functional materials for energy conversion. In this context, this study reports (i) the introduction of a pyrene anchoring group on a PNP−pincer IrI complex previously described as a selective catalyst for the electrodriven CO2 reduction (CO2RR) into CO in DMF/water mixtures, (ii) the comparison of its CO2RR activity in DMF/water mixtures with the ones of two pyrene‐free reference complexes, and (iii) its activity in pure water after immobilization onto carbon nanotubes (CNTs). Surprisingly, in homogeneous conditions we find HCOO−, instead of CO, as the main CO2 reduction product for the three catalysts. After immobilization on CNTs, even if non‐negligible competitive proton reduction reaction is observed in fully aqueous media, the complex is still able to drive CO2RR and produce HCOO− with a significantly lower overpotential with respect to solution studies. [ABSTRACT FROM AUTHOR]

A series of Cu−Mn−(La)−Zr catalysts with molecular ratios of 6 : 3 : (0.35) : 1 was synthesized by sol‐gel (CMLZ−S), co‐precipitation (CML−CP, CMLZ−CP) and hydrothermal (CMLZ−H) methods, respectively. The effects of the Mn and La on the activity of catalysts were investigated. It was found that the addition of La promoted the formation of the medium basic sites. Mn acted as an electronic promotor that transfer electrons through redox reactions, causing other metals to exhibit different valence states, thus promoting the adsorption and activation of H2 and CO2. At a certain temperature, methanol selectivity decreased in the order of CMLZ−H>CMLZ−S>CMLZ−CP>CMZ−CP. The selectivity of methanol is correlated with the distribution of basic sites. For the CMLZ−H catalyst, the highest percentage of moderate basic sites facilitated the activation of CO2, resulting in the highest selectivity of methanol. The CO2 conversion was correlated with the Cu specific surface area. [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]

Renewable electricity‐driven reduction of CO2 into value‐added chemicals has been recognized as a promising sustainable energy conversion method to achieve carbon‐neutrality. Although Sn‐based catalysts show excellent selectivity towards CO and HCOOH in CO2 reduction, the reaction activity, i. e. current density, remains quite low (<100 mA cm−2). Herein, a hierarchical bimetallic electrocatalyst consisting of Cu foam‐supported bundle‐like structure and thin amorphous SnO layer was fabricated for efficient electroreduction of CO2 to C1 products (CO and HCOOH). The hierarchical structure ensured higher large electrochemically active surface area, while the thin amorphous SnO layer could efficiently adsorb CO2, and stabilize the *CO2− intermediate formed in the rate‐determining step, thereby boosting the reaction activity of CO2 reduction. As a result, an unprecedented partial current density of 128.6 mA cm−2 was achieved for C1 products at −1.4 V vs. RHE with a Faradaic efficiency of 79.2 % in an H‐type cell. The strategy of integrating optimized structure with active site here may be beneficial to other related energy conversion systems. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 (CO2RR) is a promising solution to mitigate the ever‐increasing global carbon emission. Indium‐based catalysts have been extensively studied for catalyzing the production of formate, CO, and even multi‐carbon molecules from CO2. Rational design of the catalyst, however, is urgently needed to further improve the activity, selectivity, and stability for the sake of commercialization. Herein, we comprehensively reviewed recent progresses on the indium based CO2RR catalysts. Specifically, aspects regarding the nature of active sites, reaction mechanism, and the impact of operating conditions are overviewed. The reported indium‐based monometallic and bimetallic catalysts in the literature are summarized, as well. Future directions should be focused on the understanding of catalyst system during the reaction and under industrial‐relevant conditions. [ABSTRACT FROM AUTHOR]

The integration of metal‐based catalysts onto semiconducting electrodes provides a real benefit for the CO2 electrochemical conversion because it allows the electrochemical process to be activated by photogenerated electrons. In that context, we report here that silicon photocathodes modified with electrodeposited Bi nanostructures are highly active for the photoelectrocatalytic conversion of CO2 to formate. Through the consumed electrical charge and the electrodeposition time, it is possible to finely control both the structure and the density of the deposited catalyst. The optimal photocathode was prepared by using a 5 s electrodeposition time and exhibited the highest photocurrent density (−24.1 mA cm−2) with partial formate photocurrent density jformate=−17.4 mA cm−2 at −1.03 V vs Reversible Hydrogen Electrode (RHE), i. e. a 0.84 V overpotential for CO2 to formate conversion in CO2‐saturated 0.5 M KHCO3 solution. Such values highlight the excellent photoelectrocatalytic activity of our photocathodes. [ABSTRACT FROM AUTHOR]

Pd/ZnO catalysts with ca. 2 wt.% Pd loading employing ZnO nanocrystals with various morphologies as supports, including ZnO nanoplates (p−ZnO) predominantly exposing polar {002} facets, ZnO nanorods (r−ZnO) predominantly exposing nonpolar {100} and {101} facets, and commercial ZnO (c−ZnO) exposing random facets, have been prepared as catalysts for the catalytic reaction of CO2 hydrogenation into formic acid (FA) without the addition of base under mild conditions. A remarkable morphology‐dependence of zinc oxide in the Pd/ZnO catalysts was observed. Catalytic activities of various Pd/ZnO catalysts in CO2 hydrogenation into FA follow an order of Pd/r−ZnO>Pd/p−ZnO>Pd/c−ZnO, and all the catalysts are stable. Kinetic study, CO2‐TPD analysis, and in situ DRIFTS spectra provide evidence that all the Pd/ZnO catalysts follow a similar catalytic mechanism that CO2 activation is the rate‐determining step. Consequently, r−ZnO, possessing a higher density of weak basic sites than p−ZnO and c−ZnO, can act as a superb support to prepare Pd/r−ZnO catalyst, which is more active than Pd/p−ZnO and Pd/c−ZnO catalysts for the production of FA. These findings nicely demonstrate the crystal‐plane engineering of the metal oxide support in tuning the catalytic performance of Pd‐based catalysts for CO2 hydrogenation into FA. [ABSTRACT FROM AUTHOR]

A highly efficient carboxylative cyclization of propargylic alcohols with CO2 under atmospheric pressure catalyzed by silver (0) nanoparticles decorated reduced graphene oxide (Ag‐rGO) is reported. Ag‐rGO was fully characterized by scanning electron microscope spectra (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT‐IR) spectra, Raman spectra and X‐ray photoelectron spectroscopy (XPS). Notably, Ag‐rGO can be also applied to the construction of other value‐added chemicals (β‐oxopropylcarbamates and 2‐oxazolidinones) from CO2 at ambient conditions. In addition, Ag‐rGO is stable and reusable, which shows the potential for the practical application for CO2 capture and utilization (CCU). [ABSTRACT FROM AUTHOR]

We report on a new synthesis route for pure Sm2O3 and Sm2O3‐Ni xerogels by modifying the well‐known epoxide addition method. The resulting xerogels are used to prove the suitability of samaria as a highly effective catalyst support and to determine the optimal Ni loading. Therefore, a set of five catalysts with Ni loadings between 4 wt % and 89 wt % Ni was prepared and fully characterized by X‐ray diffraction, N2 physisorption, transmission electron microscopy and H2 temperature‐programmed reduction. Catalytic measurements reveal that the catalyst with 39 wt % Ni shows the best catalytic performance, outperforming even highly active literature known systems. Stability runs indicate that the catalyst deactivates independently of the Ni loading as well as conversion level over 600 min due to, most likely, carbonate formation. This deactivation, however, is reversible by a simple regeneration step. As shown by simultaneous CO2/CO methanation measurements, the Ni−Sm2O3 catalysts are also highly efficient for CO methanation. In this case, CO is preferentially converted to methane compared to CO2. The good samaria! A new synthesis route for pure and Ni loaded samaria xerogels is reported. The synthesized materials are applied for the hydrogenation of COx to methane. Carefully balancing the Ni loading leads to an optimal ratio of CO2 adsorption and H2 dissociation sites resulting in an exceptional conversion level. Simultaneous CO/CO2 experiments prove the flexibility and high activity of the Ni−Sm2O3 system for various applications. [ABSTRACT FROM AUTHOR]

Telomerization is a versatile tool for synthesizing unsaturated ethers, amines and other molecules starting from 1,3‐dienes and respective nucleophiles. The homogeneously catalyzed reaction has been the subject of academic and industrial research for over 50 years, offering a broad variety of substrates, catalysts and process concepts. This Minireview presents the advances and developments in this field over the last decade. The focus was on the conversion of renewable resources, the synthesis of promising new products and the development of efficient process concepts to combine these. Of great value: Telomerization is a versatile tool for synthesizing unsaturated ethers, amines and other molecules starting from 1,3 dienes and respective nucleophiles. The homogeneously catalyzed reaction has been the subject of academic and industrial research for over 50 years, offering a broad variety of substrates, catalysts and process concepts. This Minireview presents the advances and developments in this field over the last decade. [ABSTRACT FROM AUTHOR]