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At the core of carbon monoxide dehydrogenase (CODH) active site two metal ions together with hydrogen bonding scheme from amino acids orchestrate the interconversion between CO2 and CO. We have designed a molecular catalyst implementing a bimetallic iron complex with an embarked second coordination sphere with multi‐point hydrogen‐bonding interactions. We found that, when immobilized on carbon paper electrode, the dinuclear catalyst enhances up to four fold the heterogeneous CO2 reduction to CO in water with an improved selectivity and stability compared to the mononuclear analogue. Interestingly, quasi‐identical catalytic performances are obtained when one of the two iron centers was replaced by a redox inactive Zn metal, questioning the cooperative action of the two metals. Snapshots of X‐ray structures indicate that the two metalloporphyrin units tethered by a urea group is a good compromise between rigidity and flexibility to accommodate CO2 capture, activation, and reduction. [ABSTRACT FROM AUTHOR]

Construction of a "net‐zero‐emission" system through CO2 hydrogenation to methanol with solar energy is an eco‐friendly way to mitigate the greenhouse effect. Traditional CO2 hydrogenation demands centralized mass production for cost reduction with mass water electrolysis for hydrogen supply. To achieve continuous reaction with intermittent and fluctuating flow of H2 on a small‐scale for distributed application scenarios, modulating the catalyst interface environment and chemical adsorption capacity to adapt fluctuating reaction conditions is highly desired. This paper describes a distributed clean CO2 utilization system in which the surface structure of catalysts is carefully regulated. The Ni catalyst with unsaturated electrons loaded on In2O3 can reduce the dissociation energy of H2 to overcome the slow response of intermittent H2 supply, exhibiting a faster response (12 min) than bare oxide catalysts (42 min). Moreover, the introduction of Ni enhances the sensitivity of the catalyst to hydrogen, yielding a Ni/In2O3 catalyst with a good performance at lower H2 concentrations with a 15 times adaptability for wider hydrogen fluctuation range than In2O3, greatly reducing the negative impact of unstable H2 supplies derived from renewable energies. [ABSTRACT FROM AUTHOR]

The concept of green carbon science is to promote the goal of achieving carbon neutrality, the importance and urgency of which have been well‐recognized and received worldwide attention. Carbon neutrality has become the focus of research work in many fields, and correspondingly, a growing number of papers and publications have been published over the last few years. However, since carbon neutralization is a real problem that urgently requires technical solutions, the transition from fundamental research to practical applications must be accelerated. A number of research teams are bold in putting things into practice and blazing new trails. This Review summarizes the recent technological developments within the framework of green carbon science, focusing on conducted pilot tests, industrial demonstrations, and commercial applications beyond the laboratory stage. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction (CO2ER) to multi‐carbon chemical feedstocks over Cu‐based catalysts is of considerable attraction but suffers with the ambiguous nature of active sites, which hinder the rational design of catalysts and large‐scale industrialization. This paper describes a large‐scale simulation to obtain realistic CuZn nanoparticle models and the atom‐level structure of active sites for C2+ products on CuZn catalysts in CO2ER, combining neural network based global optimization and density functional theory calculations. Upon analyzing over 2000 surface sites through high throughput tests based on NN potential, two kinds of active sites are identified, balanced Cu−Zn sites and Zn‐heavy Cu−Zn sites, both facilitating C−C coupling, which are verified by subsequent calculational and experimental investigations. This work provides a paradigm for the design of high‐performance Cu‐based catalysts and may offer a general strategy to identify accurately the atomic structures of active sites in complex catalytic systems. [ABSTRACT FROM AUTHOR]

Electrochemical redox‐control is an emerging strategy for the regulation of polymerization process without the addition of external oxidants and reductants, which enables the control over composition, microstructure and properties of the polymer products. In this paper, based on the chemical selectivity of heterometallic Salen‐Co‐Mn complexes of different valences, an electrochemically switchable strategy was developed for the copolymerization of lactide (LA), CO2 and epoxides. The switchable redox reactions endowed this system with the capability to easily synthesize a multi‐block copolymer of polylactide (PLA) and polycarbonate (PC). Moreover, the multi‐block copolymer could be further modified by introducing various monomers with different microstructures and functional groups. [ABSTRACT FROM AUTHOR]

It is highly desired to achieve controllable product selectivity in CO2 hydrogenation. Herein, we report light‐induced switching of reaction pathways of CO2 hydrogenation towards CH3OH production over actomically dispersed Co decorated Pt@UiO‐66‐NH2. CO, being the main product in the reverse water gas shift (RWGS) pathway under thermocatalysis condition, is switched to CH3OH via the formate pathway with the assistance of light irradiation. Impressively, the space‐time yield of CH3OH in photo‐assisted thermocatalysis (1916.3 μmol gcat−1 h−1) is about 7.8 times higher than that without light at 240 °C and 1.5 MPa. Mechanism investigation indicates that upon light irradiation, excited UiO‐66‐NH2 can transfer electrons to Pt nanoparticles and Co sites, which can efficiently catalyze the critical elementary steps (i.e. CO2‐to‐*HCOO conversion), thus suppressing the RWGS pathway to achieve a high CH3OH selectivity. [ABSTRACT FROM AUTHOR]