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[Display omitted] Electrochemical carbon dioxide reduction reaction (CO 2 RR) is a promising technology to establish an artificial carbon cycle. Two-dimensional conjugated metal–organic frameworks (2D c-MOFs) with high electrical conductivity have great potential as catalysts. Herein, we designed a range of 2D c-MOFs with different transition metal atoms and organic ligands, TMN x O 4-x -HDQ (TM = Cr∼Cu, Mo, Ru∼Ag, W∼Au; x = 0, 2, 4; HDQ = hexadipyrazinoquinoxaline), and systematically studied their catalytic performance using density functional theory (DFT). Calculation results indicated that all of TMN x O 4-x -HDQ structures possess good thermodynamic and electrochemical stability. Notably, among the examined 37 MOFs, 6 catalysts outperformed the Cu(2 1 1) surface in terms of catalytic activity and product selectivity. Specifically, NiN 4 -HDQ emerged as an exceptional electrocatalyst for CO production in CO 2 RR, yielding a remarkable low limiting potential (U L) of −0.04 V. CuN 4 -HDQ, NiN 2 O 2 -HDQ, and PtN 2 O 2 -HDQ also exhibited high activity for HCOOH production, with U L values of −0.27, −0.29, and −0.27 V, respectively, while MnN 4 -HDQ, and NiO 4 -HDQ mainly produced CH 4 with U L values of −0.58 and −0.24 V, respectively. Furthermore, these 6 catalysts efficiently suppressed the competitive hydrogen evolution reaction. Machine learning (ML) analysis revealed that the key intrinsic factors influencing CO 2 RR performance of these 2D c-MOFs include electron affinity (E A), electronegativity (χ), the first ionization energy (I e), p-band center of the coordinated N/O atom (ε p), the radius of metal atom (r), and d-band center (ε d). Our findings may provide valuable insights for the exploration of highly active and selective CO 2 RR electrocatalysts. [ABSTRACT FROM AUTHOR]

Halide anion adsorption on transition metals can improve the performance of electrochemical CO2 reduction reaction (CO2RR), while the specific reaction mechanisms governing selective CO2RR pathways remain unclear. In this study, we reveal for the first time the distinct pathway switching between gaseous (CO) and liquid products (formate and ethanol) on the well‐defined Ag−Cu nanostructures with controlled chlorination. We show that CO2 conversion to CO on Ag/AgCl can be tuned by adjusting the thickness of AgCl layer, achieving a high selectivity over a broad potential range in a 0.5 M KHCO3 using flow cell. In contrast, the optimized Cl−Ag/Cu system enables the conversion of CO2 into liquid products including formate and ethanol with a total Faradaic efficiency (FE) nearing 100 %, delivering high current densities of 136.3 and 20.8 mA cm−2 at −1.3 V, respectively. In situ infrared experiments and theoretical calculations indicate that the lateral adsorbate of *OCHO intermediate facilitates the thermodynamics of both the CO pathway on Cl−Ag(111) and the formate pathway on Cl−Ag/Cu(111) by reducing Gibbs free energy barriers of each potential‐limit step. This work uncovers the role of chlorination in the tuning of C‐bound or O‐bound intermediates during CO2RR on Ag−Cu catalysts, determining the reaction pathway under lateral adsorbate effects. [ABSTRACT FROM AUTHOR]

Renewable electricity shows immense potential as a driving force for the carbon dioxide reduction reaction (CO2RR) in production of formate (HCOO−) at industrial current density, providing a promising path for value‐added chemicals and chemical manufacturing. However, achieving high selectivity and stable production of HCOO− at industrial current density remains a challenge. Here, we present a robust Bi0.6Cu0.4 NSs catalyst capable of regenerating necessary catalytic core (Bi−O) through cyclic voltammetry (CV) treatment. Notably, at 260 mA cm−2, faradaic efficiency of HCOO− reaches an exceptional selectivity to 99.23 %, maintaining above 90 % even after 400 h, which is longest reaction time reported at the industrial current density. Furthermore, in stability test, the catalyst was constructed by CV reconstruction to achieve stable and efficient production of HCOO−. In 20 h reaction test, the catalyst has a rate of HCOO− production of 13.24 mmol m−2 s−1, a HCOO− concentration of 1.91 mol L−1, and an energy consumption of 129.80 kWh kmol−1. In situ Raman spectroscopy reveals the formation of Bi−O structure during the gradual transformation of catalyst from Bi0.6Cu0.4 NBs to Bi0.6Cu0.4 NSs. Theoretical studies highlight the pivotal role of Bi−O structure in modifying the adsorption behavior of reaction intermediates, which further reduces energy barrier for *OCHO conversion in CO2RR. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction reaction (CO2RR) into valuable chemicals represents an effective approach for realizing carbon neutralization goals. Copper oxide‐derived catalysts are particularly promising due to their tunable electronic structures. In this study, we focused on investigating the Ag2Cu2O3 model catalyst and a mixture of CuO and Ag2O with an identical metal molar ratio (denoted an as M–CuAgO). Electrochemical CO2RR tests revealed that Ag2Cu2O3 exhibited selectivity towards ethanol, while M–CuAgO showed no selectivity towards multi‐carbon products. Characterizations of the post‐reaction materials showed differences in the specific crystal structures of the two catalysts. Further X‐ray photoelectron spectroscopy (XPS) analysis demonstrated that the Ag2Cu2O3 structure, after the reaction, facilitated the transfer of electrons from Cu to Ag, thereby promoting the formation of multi‐carbon products. This work underscores the significance of structural design in precatalysts and opens up new avenues for the design of high‐performance catalysts. [ABSTRACT FROM AUTHOR]

This study investigates the detailed mechanism of CO2 conversion to CO using the manganese(I) diimine electrocatalyst [Mn(pyrox)(CO)3Br], synthesized by Christoph Steinlechner and coworkers. Employing density functional theory calculations, we thoroughly explore the electrocatalytic pathway of CO2 reduction alongside the competing hydrogen evolution reaction. Our analysis reveals the significant role of diimine nitrogen coordination in enhancing the electron density of the Mn center, thereby favoring both CO2 reduction and hydrogen evolution reaction thermodynamically. Furthermore, we observe that triethanolamine (TEOA) stabilizes transition states, aiding in CO2 fixation and reduction. The critical steps influencing the reaction rate involve breaking the MnC(O)–OH bond during CO2 reduction and cleaving the MnH–H–TEOA bond in the hydrogen evolution reaction. We explain the preference for CO2 conversion to CO over H2 evolution due to the higher energy barrier in forming the Mn-H2 species during H2 production. Our findings suggest the potential for tuning the electron density of the Mn center to enhance reactivity and selectivity in CO2 reduction. Additionally, we analyze potential competing reactions, focusing on electrocatalytic processes for CO2 reduction and evaluating “protonation-first” and “reduction-first” pathways through density functional theory calculations of redox potentials and Gibbs free energies. This analysis indicates the predominance of the “reduction-first” pathway in CO production, especially under high applied potential conditions. Moreover, our research highlights the selectivity of [Mn(pyrox)(CO)3Br] toward CO production over HCOO− and H2 formation, proposing avenues for future research to expand upon these findings by using larger basis sets and exploring additional functionalized ligands. [ABSTRACT FROM AUTHOR]

The escalating concern regarding the release of CO2 into the atmosphere poses a significant threat to the contemporary efforts in mitigating climate change. Amidst a multitude of strategies for curtailing CO2 emissions, the electrochemical CO2 reduction presents a promising avenue for transforming CO2 molecules into a diverse array of valuable gaseous and liquid products, such as CO, CH3OH, CH4, HCO2H, C2H4, C2H5OH, CH3CO2H, 1‐C3H7OH and others. The mechanistic investigations of gaseous products (e. g. CO, CH4, C2H4, C2H6 and others) broadly covered in the literature. There is a noticeable gap in the literature when it comes to a comprehensive summary exclusively dedicated to coherent roadmap for the designing principles for a selective catalyst all possible liquid products (such as CH3OH, C2H5OH, 1‐C3H7OH, 2‐C3H7OH, 1‐C4H9OH, as well as other C3‐C4 products like methylglyoxal and 2,3‐furandiol, in addition to HCO2H, AcOH, oxalic acid and others), selectively converted by CO2 reduction. This entails a meticulous analysis to justify these approaches and a thorough exploration of the correlation between materials and their electrocatalytic properties. Furthermore, these insightful discussions illuminate the future prospects for practical applications, a facet not exhaustively examined in prior reviews. [ABSTRACT FROM AUTHOR]

Fine‐tuning the interfacial sites within heterogeneous catalysts is pivotal for unravelling the intricate structure–property relationship and optimizing their catalytic performance. Herein, a simple and versatile mixed‐dimensional assembly approach is proposed to create nanocrystal‐on‐nanowire superstructures with precisely adjustable numbers of biphasic interfaces. This method leverages an efficient self‐assembly process in which colloidal nanocrystals spontaneously organize onto Ag nanowires, driven by the solvophobic effect. Importantly, varying the ratio of the two components during assembly allows for accurate control over both the quantity and contact perimeter of biphasic interfaces. As a proof‐of‐concept demonstration, a series of Au‐on‐Ag superstructures with varying numbers of Au/Ag interfaces are constructed and employed as electrocatalysts for electrochemical CO2‐to‐CO conversion. Experimental results reveal a logarithmic linear relationship between catalytic activity and the number of Au/Ag interfaces per unit mass of Au‐on‐Ag superstructures. This work presents a straightforward approach for precise interface engineering, paving the way for systematic exploration of interface‐dependent catalytic behaviors in heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

To tackle significant environmental and energy challenges from increased greenhouse gas emissions in the atmosphere, we propose a method that synergistically combines cost-efficient integrated systems with parallel catalysis to produce high-value chemicals from CO2, NO, and other gases. We employed asymmetrically stretched InO5S with symmetry-breaking indium sites as a highly efficient trifunctional catalysts for NO reduction, CO2 reduction, and O2 reduction. Mechanistic studies reveal that the symmetry-breaking at indium sites substantially improves d-band center interactions and adsorption of intermediates, thereby enhancing trifunctional catalytic activity. Employed in a flow electrolysis system, the catalyst achieves continuous and flexible production of NH3, HCOO-, and H2O2, maintaining over 90% Faradaic efficiency at industrial scales. Notably, the parallel electrolysis device reported in this study effectively produces high-value products like NH4COOH directly from greenhouse gases in pure water, offering an economically efficient solution for small molecule synthesis and unique insights for the sustainable conversion of inexhaustible gases into valuable products. Therefore, this work possesses considerable potential for future practical applications in sustainable industrial processes. [ABSTRACT FROM AUTHOR]

Using particle swarm optimization methodology for crystal structure prediction and first-principles density functional theory, we predicted a phosphorus silicide (PSi) monolayer that meets the thermodynamical, dynamical, and mechanical stability requirements. The PSi monolayer possesses a graphene-like honeycombed structure with a small puckering corresponding to a distance, d, of 0.939 Å and is metallic under the PBE or HSE06 functional. Based on the metallic property, we first found that the PSi monolayer can be used as the anode of a lithium-ion battery with a barrier energy of 0.65 eV and a theoretical capacity of 306.3 mA g h–1, for which the puckering structure influences the diffusion of Li ions on the surface of the PSi monolayer. We further studied the adsorption behavior of CO2, and the Si site in the PSi monolayer has unexpected activity toward adsorption and activation of CO2, showing that the PSi monolayer exhibits superior catalytic performance for the CO2 reduction reaction (CO2RR) to CH4 with the optimal path of CO2RR as CO2 → *COOH → *CO → *COH → *CHOH → *CH → *CH2 → *CH3 → *CH4. This work demonstrates great potential applications of the PSi monolayer on the energy storage battery and low-cost electrocatalytic materials for the efficient separation and conversion of CO2, respectively. [ABSTRACT FROM AUTHOR]

Based on the experimentally reported stable and conductive two-dimensional covalent organic frameworks with copper phthalocyanine (CuPc) as building block and cyan substituted phenyl as connector (CuCOF-CN) as an electrocatalyst for CO2 reduction reaction (RR), first principle calculations were performed on CuCOF-CN and its analog with the CN being replaced by H (CuCOF). Comparatively studied on the crystal structures, electronic properties, and CO2RR performance of the two catalysts found that CuCOF has reduced crystal unit size, more positive charge on Cu and CuPc segments, smaller band gap, and lower reaction barrier for CO2 RR than CuCOF-CN. CuCOF is proposed to be good potential electrocatalyst with good environment friendliness. The substituent effect and structure-property-performance relationship would help for designing and fabricating new electrocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Atomically dispersed catalyst with single Cu atom and atomic Ni clusters was prepared. • Cu SA Ni AC /NMHCS achieves a high FE CO of over 90% across a wide potential range. • Cu SA Ni AC /NMHCS shows the highest FE CO of 98 % at − 0.9 V vs. RHE. • Cu SA Ni AC /NMHCS exhibits excellent long-term stability for CO 2 RR to produce CO. • Positively shifted ε d of Ni 3 d orbital contributes to the enhanced CO 2 RR performance. The rational design of catalysts with atomic dispersion and a deep understanding of the catalytic mechanism is crucial for achieving high performance in CO 2 reduction reaction (CO 2 RR). Herein, we present an atomically dispersed electrocatalyst with single Cu atom and atomic Ni clusters supported on N-doped mesoporous hollow carbon sphere (Cu SA Ni AC /NMHCS) for highly efficient CO 2 RR. Cu SA Ni AC /NMHCS demonstrates a remarkable CO Faradaic efficiency (FE CO) exceeding 90% across a potential range of −0.6 to −1.2 V vs. reversible hydrogen electrode (RHE) and achieves its peak FE CO of 98% at −0.9 V vs. RHE. Theoretical studies reveal that the electron redistribution and modulated electronic structure—notably the positive shift in d-band center of Ni 3 d orbital—resulting from the combination of single Cu atom and atomic Ni clusters markedly enhance the CO 2 adsorption, facilitate the formation of *COOH intermediate, and thus promote the CO production activity. This study offers fresh perspectives on fabricating atomically dispersed catalysts with superior CO 2 RR performance. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO2 reduction (ECR) has emerged as one of the most promising strategies to alleviate the energy crisis and CO2 pollution, for which a wide variety of catalysts are under development. Metal‐organic frameworks (MOFs) with clear and designable structures are an excellent platform for ECR. In this study, two isostructural N, O‐coordinated Zn‐MOFs, FJU‐126‐4F, and FJU‐126‐CH3, based on terephthalic acid ligand with different groups (one is ─4F and the other is ─CH3) on the benzene ring, have been constructed for ECR catalysts. Significantly, the different functional groups make the performance difference of ECR. The maximum Faraday efficiency of formate (FEformate) for FJU‐126‐4F is 60.5% with the partial current density of formate (jformate) of −19.35 mA cm−2 at −1.47 V, while the optimum FEformate of FJU‐126‐CH3 is 50.2% with the jformate of −10.04 mA cm−2 at −1.57 V. This work provides an insight into the rational design of MOF catalysts for ECR. [ABSTRACT FROM AUTHOR]

The era of an energy economy driven by “carbon neutrality” is putting forward stricter requirements for the use of carbon resources and the governance of CO2. Electrochemical reduction of carbon dioxide reaction (CO2RR), driven by renewable energy, is a practical energy storage technology with broad application prospects. It can reduce CO2 into carbon‐based fuels and chemical products. Among them, multi‐carbon (C2+) products have higher energy density and larger market size, and can significantly reduce the global demand for fossil fuels and close the artificial carbon cycle. Introducing additional active sites into Cu‐based catalysts to prepare dual‐site tandem catalysts can regulate the electronic and geometric structure of the catalysts, break linear scale relationships, reduce reaction potential barriers, and bring superb and stable catalytic performance. Various types of dual‐site tandem catalysts are developed, and the understanding of the tandem effect is pushed to a higher level. This paper reviews several typical dual‐site tandem catalysts: atom–atom dual‐site tandem catalysts, atom‐particle dual‐site tandem catalysts, particle–particle dual‐site tandem catalysts, and heterogeneous interface dual‐site tandem catalysts. It then deeply analyzes the reaction mechanism and research progress of these advanced catalysts in CO2RR. In addition, the challenges and opportunities faced by such catalysts are also discussed. [ABSTRACT FROM AUTHOR]

Electrocatalytic reduction of CO2 into C2 products of high economic value provides a promising strategy to realize resourceful CO2 utilization. Rational design and construct dual sites to realize the CO protonation and C−C coupling to unravel their structure‐performance correlation is of great significance in catalysing electrochemical CO2 reduction reactions. Herein, Cu−Cu dual sites with different site distance coordinated by halogen at the first‐shell are constructed and shows a higher intramolecular electron redispersion and coordination symmetry configurations. The long‐range Cu−Cu (Cu−I−Cu) dual sites show an enhanced Faraday efficiency of C2 products, up to 74.1 %, and excellent stability. In addition, the linear relationships that the long‐range Cu−Cu dual sites are accelerated to C2H4 generation and short‐range Cu−Cu (Cu−Cl−Cu) dual sites are beneficial for C2H5OH formation are disclosed. In situ electrochemical attenuated total reflection surface enhanced infrared absorption spectroscopy, in situ Raman and theoretical calculations manifest that long‐range Cu−Cu dual sites can weaken reaction energy barriers of CO hydrogenation and C−C coupling, as well as accelerating deoxygenation of *CH2CHO. This study uncovers the exploitation of site‐distance‐dependent electrochemical properties to steer the CO2 reduction pathway, as well as a potential generic tactic to target C2 synthesis by constructing the desired Cu−Cu dual sites. [ABSTRACT FROM AUTHOR]

Graph neural networks (GNNs) have drawn more and more attention from material scientists and demonstrated a strong capacity to establish connections between structures and properties. However, with only unrelaxed structures provided as input, few GNN models can predict the thermodynamic properties of relaxed configurations with an acceptable level of error. In this work, a multi‐task (MT) architecture based on DimeNet++ and mixture density networks is developed to improve the performance of such task. Taking CO adsorption on Cu‐based single‐atom alloy catalysts as an example, the method can reliably predict CO adsorption energy with a mean absolute error of 0.087 eV from the initial CO adsorption structures without costly first‐principles calculations. Compared to other state‐of‐the‐art GNN methods, the model exhibits improved generalization ability when predicting the catalytic performance of out‐of‐distribution configurations, built with either unseen substrate surfaces or doping species. Further, the enhancement of expressivity has also been demonstrated on the IS2RE predicting task in the Open Catalyst 2020 project. The proposed MT GNN strategy can facilitate the catalyst discovery and optimization process. [ABSTRACT FROM AUTHOR]

The attenuated total reflection-surface-enhanced infrared absorption spectroscopy (SEIRAS) activity of electrodeposited Cu nanoparticles on indium tin oxide-modified Si internal reflection elements is reported. The solution in the cell is easily, and repeatedly, exchanged between a copper deposition bath and a solution containing 4-methoxypyridine through the use of a flow-through spectroelectrochemical cell. 4-methoxypyridine is a convenient SEIRAS probe molecule exhibiting potential-dependent adsorption/desorption on the copper surface. Successive amounts of copper are deposited and then evaluated for electrochemical SEIRAS activity without the need to expose the Cu surface to ambient conditions. It is found that copper deposition charge densities of approximately 60 mC cm−2 exhibit the largest amplitude and most symmetric IR absorption peaks of the investigated electrodeposition conditions. Scanning electron microscopy images of the different Cu charge density films are correlated with the SEIRAS results and establish that close-packed two-dimensional, percolated arrays of oblate, ellipsoidal Cu nanoparticles are responsible for ideal SEIRAS performance and three-dimensional aggregates of larger particles should be avoided. Textured films of Cu nanoparticles are used to determine the adsorbed species present on the copper surface during CO2 electroreduction at low overpotentials. Evidence of adsorbed CO and COH is found at lower overpotentials than those described in previous reports. [ABSTRACT FROM AUTHOR]

By adjusting the synthesis variation of hollow urchin-like Ni-NC(HU)-x catalyst, the content of pyridinic-N was adjusted, and the dual-atoms site was formed. Ni-NC(HU)-50 showed the best catalytic performance with FE CO of 97.2% at −0.9 V vs. RHE and sustains above 95% within 50 h. [Display omitted] Dual-atoms catalysts (DACs), while inheriting the advantages of maximum atom utilization ratio and excellent selectivity of single-atom catalysts (SACs), can better enhance the catalytic activity through the synergy of adjacent atoms. Therefore, DACs are considered to be very potential catalysts for CO 2 to CO conversion. Its catalytic activity is greatly influenced by the coordination environment and morphology. Here, hollow urchin-like Ni N C catalysts (Ni-NC(HU)-x, x = 100, 50, 25, 0) were synthesized using urchin-like nickel particles as template. By adjusting the amount of additional nitrogen source, the percentage content of pyridinic-N was adjusted as well as further affecting the coordination environment. Among them, Ni-NC(HU)-50, which had the highest content of pyridinic-N, formed a dual-atoms coordination structure and had the best catalytic performance that the CO Faradaic efficiency (FE CO) reached 97.2 % at −0.9 V vs. reversible hydrogen electrode (RHE) and sustained above 95 % within 50 h. In-situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) and density functional theory (DFT) calculations showed that Ni-NC(HU)-50 exhibited the best performance of CO 2 reduction reaction (CO 2 RR) by lowering the *COOH formation free energy barrier and its favorable dual desorption mechanism of *CO L and *CO B. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 and H2O to synthesize gas (H2 and CO mixture) is of significant interest due to established industrial pathways to tune the H2 to CO composition to generate an array of valuable products including methanol, synthetic fuel, synthetic natural gas, and hydrogen. However, controlled H2:CO ratios are challenging on CO-active electrocatalysts like silver. We demonstrate that applying laser engineering to adjust the surface wetting state of a silver electrocatalyst with water contact angles θw ranging from 47° and 135°, H2:CO ratios can be tuned from 1 to 4 at modest potentials (−0.7 V versus RHE, RHE—reversible hydrogen electrode) with almost total unity Faradaic efficiency. Both hydrophilic (θw = 47°) and more hydrophobic (θw = 135°) samples showed an increasing H2:CO trend with rising potentials (0.7–1.2 V versus RHE) due to mass transport. Conversely, silver electrocatalyst with θw = 110° exhibited a constant H2:CO ratio of 4. This indicates catalyst wettability potentially affects *H and *HOCO intermediates' adsorption, impacting H2:CO ratios. Our results show the feasibility of syngas composition control on silver catalysts via surface wettability, providing a simpler alternative to complex multicomponent electrocatalytic systems. [ABSTRACT FROM AUTHOR]

Highlights We revealed a universal self-adaptive structural reconstruction from Cu2O to Cu@CuxO composites, ending with feeding gas-dependent microstructures and catalytic performances. We uncovered a CO2-induced passivation behavior by identifying a reduction-resistant but catalytic active Cu(I)-rich amorphous layer. We designed and fabricated hollow Cu2O nanospheres, demonstrating durable electrolysis at a partial current density of −200 mA cm−2 in producing C2H4 with an FE of up to 61% at −0.6 VRHE.

Abstract Based on the experimentally reported stable and conductive two-dimensional covalent organic frameworks with copper phthalocyanine (CuPc) as building block and cyan substituted phenyl as connector (CuCOF-CN) as an electrocatalyst for CO2 reduction reaction (RR), first principle calculations were performed on CuCOF-CN and its analog with the CN being replaced by H (CuCOF). Comparatively studied on the crystal structures, electronic properties, and CO2RR performance of the two catalysts found that CuCOF has reduced crystal unit size, more positive charge on Cu and CuPc segments, smaller band gap, and lower reaction barrier for CO2 RR than CuCOF-CN. CuCOF is proposed to be good potential electrocatalyst with good environment friendliness. The substituent effect and structure-property-performance relationship would help for designing and fabricating new electrocatalysts.

The adjacent single metal atom and Fe 6 nanoparticle co-assisted Ni-N 4 configurations provided the multi-metal active sites to synergistically boost CO 2 activation and reduction to CO at high metal loading. [Display omitted] Single transition metal (TM) atom embedded in nitrogen-doped carbon materials with M−N x −C configuration have emerged as a promising class of electrocatalysts for electrochemical CO 2 reduction (CO 2 RR). However, at high TM atom densities, a comprehensive understanding of the active site structure and reaction mechanisms remains a significant challenge, yet it is crucial for enhancing CO 2 RR performance. In this work, we use first-principles calculations to investigate the electrocatalytic performance of Ni-N 4 sites for CO2 reduction to CO, co-assisted by neighboring TM atoms and a Fe 6 nanoparticle. Unlike many previously studied Ni-N 4 catalysts that maintain a linear CO 2 structure, the combination of adjacent TM atoms and Fe 6 induces bending and activation of CO 2 at the Ni site, enhancing its protonation to form key *COOH intermediate while maintaining efficient *CO desorption. The newly designed hybrid electrocatalyst demonstrates a synergistic effect of multi-metal sites in boosting CO 2 reduction to CO. Specifically, the TM atom facilitates C–Ni bond formation between the Ni site and *CO 2 /*COOH species, while Fe 6 forms an Fe...O coordination bond. Detailed analysis of reaction mechanisms and energetics show that Ni-N 4 , co-assisted by a single TM atom and Fe 6 (especially TM = Ni, Cu, or Ag), exhibits enhanced catalytic activity for CO production with a low limiting potential of −0.5 V. This work presents an effective strategy for improving the catalytic activity of single-atom catalysts (SACs) at high metal content. [ABSTRACT FROM AUTHOR]

The production of Li2CO3/C through CO2 reduction reaction in nonaqueous systems is a complex four‐electron, multi‐step process, and the short existence time of intermediate monomers is not conducive to observation, which causes great difficulties in clarifying and regulating the CO2 reduction path. Herein, ferrocene (Fc) as a functional additive into the electrolyte can stabilize the discharge intermediates and favor the occurrence of the two‐electron reaction path during CO2RR, which leads to more stable operation of the Li‐CO2 battery; with the assistance of Fc, the CO2 reduction pathway in Li‐CO2 battery is also clarified. Theoretical calculation analysis combined with experimental characterization observation confirms that Fc can shorten the CO2 reduction distance through interaction with CO2 and affecting the solvent environment around Li+, stabilize intermediate products to clarify the discharge path. The existence time of intermediates and discharge depth of the battery are key factors affecting the CO2 reduction pathway. The Li2C2O4 formed by CO2 reduction through the 2‐electron pathway is more favorable for the reversible operation of the Li‐CO2 battery than Li2CO3/C through the 4‐electron pathway. This work provides inspiration for clarifying the reaction mechanism and regulating the CO2 reduction pathway to improve the electrochemical performance of Li‐CO2 battery in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] The acidic CO 2 reduction reaction (CO 2 RR) offers a promising approach to mitigate CO 2 reactant loss and carbonate deposition, which are challenging issues in alkaline or neutral electrolytes. However, the hydrogen evolution reaction (HER) competes in the proton-rich environment near the catalyst surface as a side reaction, reducing the energy efficiency of generating multi-carbon (C 2+) products. In this work, we proposed a palladium (Pd) doping strategy in a copper (Cu)-based catalyst to stabilize polarized Cu0-Cu+ sites, thus enhancing the C C coupling step during the CO 2 RR while suppressing HER. At an optimal doping ratio of 6%, the Pd dopants were well dispersed as single atoms without aggregation, allowing for the stabilization of subsurface oxygen (O Sub), preserving the polarized Cu0-Cu+ active sites, and reducing the energy barrier of C C coupling. The Pd-doped Cu/Cu 2 O catalyst exhibited a peak Faradaic efficiency (FE) of 64.0% for C 2+ products with a corresponding C 2+ partial current density of 407.1 mA∙cm−2 at −2.18 V versus a reversible hydrogen electrode, a high CO 2 single-pass conversion efficiency (SPCE) of 73.2%, as well as a high electrochemical stability of ∼ 150 h at industrially relevant current densities, thus suggesting a potential approach for tuning the electrocatalytic CO 2 performances in acidic environments with higher carbon conversion efficiencies. [ABSTRACT FROM AUTHOR]

The strategic manipulation of the interaction between a central metal atom and its coordinating environment in single-atom catalysts (SACs) is crucial for catalyzing the CO2 reduction reaction (CO2RR). However, it remains a major challenge. While density-functional theory calculations serve as a powerful tool for catalyst screening, their time-consuming nature poses limitations. This paper presents a machine learning (ML) model based on easily accessible intrinsic descriptors to enable rapid, cost-effective, and high-throughput screening of efficient SACs in complex systems. Our ML model comprehensively captures the influences of interactions between 3 and 5d metal centers and 8 C, N-based coordination environments on CO2RR activity and selectivity. We reveal the electronic origin of the different activity trends observed in early and late transition metals during coordination with N atoms. The extreme gradient boosting regression model shows optimal performance in predicting binding energy and limiting potential for both HCOOH and CO production. We confirm that the product of the electronegativity and the valence electron number of metals, the radius of metals, and the average electronegativity of neighboring coordination atoms are the critical intrinsic factors determining CO2RR activity. Our developed ML models successfully predict several high-performance SACs beyond the existing database, demonstrating their potential applicability to other systems. This work provides insights into the low-cost and rational design of high-performance SACs. [ABSTRACT FROM AUTHOR]

Dual‐single‐atom catalysts (DSACs) are the next paradigm shift in single‐atom catalysts because of the enhanced performance brought about by the synergistic effects between adjacent bimetallic pairs. However, there are few methods for synthesizing DSACs with precise bimetallic structures. Herein, a pre‐coordination strategy is proposed to precisely synthesize a library of DSACs. This strategy ensures the selective and effective coordination of two metals via phthalocyanines with specific coordination sites, such as −F− and −OH−. Subsequently, in situ confinement inhibits the migration of metal pairs during high‐temperature pyrolysis, and obtains the DSACs with precisely constructed metal pairs. Despite changing synthetic parameters, including transition metal centers, metal pairs, and spatial geometry, the products exhibit similar atomic metal pairs dispersion properties, demonstrating the universality of the strategy. The pre‐coordination strategy synthesized DSACs shows significant CO2 reduction reaction performance in both flow‐cell and practical rechargeable Zn‐CO2 batteries. This work not only provides new insights into the precise synthesis of DSACs, but also offers guidelines for the accelerated discovery of efficient catalysts. [ABSTRACT FROM AUTHOR]

The CO2 electroreduction reaction using sustainable electricity emerges as a viable strategy to produce high‐value‐added and profitable chemicals. The achievement of superior activity at a lower overpotential and higher selectivity in a wide potential window is vitally important for large‐scale industrial applications. Herein, a carbon‐composite amorphous porous BiSbOx nanotube with abundant unsaturated sites is reported to boost the conversion of CO2 to formate, exhibiting a formate selectivity of >90% in an extremely broad range of potentials from −0.5 to −1.4 V versus reversible hydrogen electrode (RHE) and a maximal energy conversion efficiency of 77.1%. Importantly, pure formic acid solution is directly obtained in a solid‐electrolyte cell for industrial‐scale applications. The porous tubular structure can expose more catalytic active sites, accelerate the mass transfer, and show fast surface charge transfer. Moreover, the unique coordination‐unsaturated Sb‐stabilized BiO8−x site can not only enhance the adsorption and activation of CO2 but also reasonably balance the stabilization and hydrogenation of *OCHO intermediate, thus leading to its obviously higher catalytic performance. As a result, a novel amorphous porous BiSbOx nanotube is successfully designed for efficient CO2 electroreduction, which may shed new light on developing many more amorphous composite metal oxide catalysts for conversion of inert small molecules. [ABSTRACT FROM AUTHOR]

Metal‐organic framework (MOF) materials have attracted much attention due to their diverse topological structures, excellent adsorption capacity, and unique physicochemical properties, which hold great promise in catalytic CO2 reduction reaction (CO2RR). However, the original MOFs materials have disadvantages such as poor electrical conductivity, high diffusion barrier and limited accessible catalytic sites, which seriously limit their application in CO2RR. Therefore, many structural engineering strategies have been used to improve the CO2RR performance of the MOFs materials. In this review, we mainly review the four main structure engineering strategies, i. e. crystal engineering, 2D engineering, heterostructure engineering and MOF derivatives engineering, in enhancing the catalytic CO2RR performance of the MOFs. We hope that this review will not only provide insights for the rational design of efficient MOFs materials for the CO2RR, but also stimulate more research work in this field. [ABSTRACT FROM AUTHOR]

Although gapped grain boundaries have often been observed in bulk and nanosized materials, and their crucial roles in some physical and chemical processes have been confirmed, their acquisition at ultrasmall nanoscale presents a significant challenge. To date, they had not been reported in metal nanoparticles smaller than 2 nm owing to the difficulty in characterization and the high instability of grain boundary (GB) atoms. Herein, we have successfully developed a synthesis method for producing a novel chiral nanocluster Au78(TBBT)40 (TBBT=4‐tert‐butylphenylthiolate) with a 26‐atom gapped and rotated GB. This nanocluster was precisely characterized using single‐crystal X‐ray crystallography and mass spectrometry. Additionally, an offset atomic defect linked to the peripheral Au(TBBT)2 staple was found in the structure. Comparing it to similarly face‐centered cubic‐structured Au36(TBBT)24, Au44(TBBT)28, Au52(TBBT)32, Au92(TBBT)44, and ~5 nm nanocrystals, the bridging Au78(TBBT)40 nanocluster exhibited higher catalytic activity in the electroreduction of CO2 to CO. This enhanced activity was explained through density functional theory calculations and X‐ray photoelectron spectroscopy analysis, which highlight the impact of GBs and point defects on the surface properties of metal nanoclusters in balancing intermediate adsorption and product desorption. [ABSTRACT FROM AUTHOR]

Electrochemical carbon dioxide (CO2) reduction reaction (CO2RR) to valuable liquid fuels, such as formic acid/formate (HCOOH/HCOO−) is a promising strategy for carbon neutrality. Enhancing CO2RR activity while retaining high selectivity is critical for commercialization. To address this, we developed metal‐doped bismuth (Bi) nanosheets via a facile hydrolysis method. These doped nanosheets efficiently generated high‐purity HCOOH using a porous solid electrolyte (PSE) layer. Among the evaluated metal‐doped Bi catalysts, Co‐doped Bi demonstrated improved CO2RR performance compared to pristine Bi, achieving ~90 % HCOO− selectivity and boosted activity with a low overpotential of ~1.0 V at a current density of 200 mA cm−2. In a solid electrolyte reactor, Co‐doped Bi maintained HCOOH Faradaic efficiency of ~72 % after a 100‐hour operation under a current density of 100 mA cm−2, generating 0.1 M HCOOH at 3.2 V. Density functional theory (DFT) results revealed that Co‐doped Bi required a lower applied potential for HCOOH generation from CO2, due to stronger binding energy to the key intermediates OCHO* compared to pure Bi. This study shows that metal doping in Bi nanosheets modifies the chemical composition, element distribution, and morphology, improving CO2RR catalytic activity performance by tuning surface adsorption affinity and reactivity. [ABSTRACT FROM AUTHOR]

This paper presents a feature-centric strategy for predicting adsorption energies of key CO2 reduction reaction (CO2RR) adsorbates, CO and H species, utilizing density functional theory-based calculations for eight adsorption sites and considering alloying effects of nine transition metals at single-atom concentrations. Here, we explore a class of materials consisting of a majority host metal where individual atoms of a different element are dispersed called single-atom alloys (SAA). A total of eight feature selection methods are assessed within Gradient Boosting Regression and Linear Regression models. This study proposes a practical and effective two-stage approach that narrows down the initial 86 features to subsets of 10 and 7 for CO and H adsorption energy predictions, respectively, with the arithmetic mean of valence electrons (VE-am) feature consistently emerging as highly influential, validated through permutation and Shapley additive explanations-based feature importance analyses. The models exhibit robust performance on unseen data, indicating their generalization capability. The findings emphasize VE-am as a potential key machine learning feature for CO2RR on SAA surfaces and underline the effectiveness of the feature-centric approach in understanding feature impacts in machine learning models for CO2RR on SAA systems. Additionally, while other features based on structural, electronic and elemental properties may not individually impact the model significantly, their collective contribution plays a vital role in achieving more accurate adsorption energy predictions. [ABSTRACT FROM AUTHOR]

The electrocatalytic conversion of CO2 to produce fuels and chemicals holds great promise, not only to provide an alternative to fossil feedstocks, but also to use renewable electricity to convert and recycle the greenhouse gas CO2 to mitigate climate problems. However, the selectivity and reaction rates for the conversion of CO2 into desirable carbon-based products, especially multicarbon products with high added value, are still insufficient for commercial applications, which is attributed to insufficiently favourable microenvironmental conditions in the vicinity of the catalyst. The construction of catalysts/electrodes with confined structures can effectively improve the reaction microenvironment in the vicinity of the electrodes and thus effectively direct the reaction towards the desired pathway. In this review, we firstly introduce the effects of the microenvironment at the electrode-electrolyte interface including local pH, local intermediate concentration, and local cation concentration on CO2 reduction reaction (CO2RR) as well as the mechanism of action, and then shed light on the microenvironmental modulation within the confined space, and finally and most importantly, introduce the design strategy of CO2RR catalyst/electrode based on the confinement effect. [ABSTRACT FROM AUTHOR]

Electrocatalytic carbon dioxide reduction reaction (CO 2 RR) offers a promising pathway towards achieving carbon neutrality. However, its efficiency is hindered by the sluggish oxygen evolution reaction (OER) at the anode, which consumes a significant portion of the energy input. Herein, we report an effective strategy to replace OER with energy efficient alcohol oxidation reactions to produce value-added products at both cathode and anode of the electrolyzer. In an integrated cell, CO 2 RR is carried out at cathode using tin oxide deposited on porous copper (SnO x @pCu@CF) as an electrocatalyst while alcohol oxidation reactions (methanol, ethanol, benzyl alcohol) are conducted on porous copper (pCu@CF) anode in alkaline electrolyte. Over 89% selectivity for the cathodic reduction of CO 2 into formate and almost 100% selectivity for anodic oxidation of methanol to formate, ethanol to acetate and benzyl alcohol to benzoate are achieved at high current densities within a wide potential range. The SnO x @pCu@CF//pCu@CF two-electrode arrangement required 100 mV less potential for the overall methanol-assisted CO 2 RR as compared to water oxidation assisted CO 2 RR with simultaneous production of valuable formate at both anode and cathode This study underscores the potential of coupling CO 2 RR with viable alternative oxidation reactions as a theoretically and technically feasible approach as well as holds significant promise for delivering substantial economic benefits. [Display omitted] • Value-added products are concurrently generated at both the anode and cathode. • Over 89% formate selectivity for cathodic CO 2 reduction is achieved. • 100% selectivity for anodic oxidation of methanol to formate, ethanol to acetate and benzyl alcohol to benzoate is achieved. • Lower potential is required for overall alcohol-oxidation assisted CO 2 RR as compared to the water oxidation assisted CO 2 RR. [ABSTRACT FROM AUTHOR]

Perovskite (ABO 3) materials are commonly used as cathodes for solid oxide electrolysis cells (SOECs), but their electrochemical performance is poor due to the low CO 2 adsorption and conductivity. Herein, we design an A-site deficient (La 0.5 Sr 0.5) 0.95 Fe 0.85 Mn 0.1 Ni 0.05 O 3-δ (95LSFMNi) perovskite cathode with rich oxygen vacancy and Ni–Fe alloy to enhance the CO 2 adsorption. The surface precipitated Ni–Fe alloy nanoparticles introduce more oxygen vacancies into the matrix and increase the active sites for CO 2 adsorption, enhancing the electrochemical reduction reaction for CO 2 (CO 2 RR). Fe element exsolution was stimulated after the Ni reduction, and Fe content in the nanoparticles increased with the reduced time. The 95LSFMNi with in-situ dissolved Ni–Fe particles exhibits a doubled conductivity than the parent La 0.5 Sr 0.5 Fe 0.9 Mn 0.1 O 3-δ (LSFM) at 800 °C and 5%H 2 /Ar. In addition, the electrolysis current density at 1.6 V and 800 °C reaches 1.09 A cm−2, representing a 28.2% increase compared to the LSFM. These findings demonstrate that the in-situ precipitated nano Ni–Fe particles are highly effective in enhancing the catalytic ability of CO 2 RR. • In situ construction of Ni–Fe NPs to increase the active sites for CO 2 RR. • Nonstoichiometric regulation of the A-site induces B-site precipitation. • The pure CO 2 electrolysis of 95LSFMNi is improved by 28.2% compared to LSFM. [ABSTRACT FROM AUTHOR]

Developing atomically dispersed metal on nitrogen‐doped carbon (M─N─C) catalyst provides a promising strategy to convert CO2 into high‐valued chemicals and achieve artificially closed carbon cycles. However, it is challenging to tune the structure and coordination of N─M bond that further improve the intrinsic activity and selectivity of CO2RR. Herein, CuNi atomic clusters embedded in Ni/Cu dual atomic sites catalysts (CuNiAC@Ni/Cu─N─C) are designed and successfully manipulated to regulate the coordination environment for M─N─C catalysts to enhance the CO2 electroreduction reaction (CO2RR). The most active configuration in CuNiAC@Ni/Cu─N─C catalyst is CuNi atomic cluster connected with 2N‐bridged (Ni‐Cu)N5, in which two N atoms are shared with NiN4 and CuN3 moieties verified by both systematic advanced characterizations and density function theory (DFT) calculations. The results have revealed the integration between CuNi atomic cluster and N4Ni/CuN3 dual‐metal atomic sites that optimize the electronic redistribution and narrow the bandgap, thereby decreasing the energy barrier of the potential determination step and promoting CO production. [ABSTRACT FROM AUTHOR]

The Faraday efficiency of CO 2 electroreduction to CO catalyzed by metalloporphyrins (MTPP, M = Fe, Co, Cu, Zn and Ni) is linearly related to the reaction energy barrier of the first proton-coupled electron reduction. [Display omitted] • Five metalloporphyrins(MTPPs) with different metal centers are compared for CO 2 RR. • CO 2 RR mechanism on MTPPs are calculated by first-principles calculations. • CoTPP exhibits the best CO 2 RR activity and selectivity. • The results of theoretical calculation are well verified by experimental tests. • The linear correlation between the selectivity of CO and the key energy barrier is revealed. Metal-functionalized porphyrin-like graphene structures are promising electrocatalysts for carbon dioxide reduction reaction (CO 2 RR) as their metal centers can modulate activity. Yet, the role of metal center of metalloporphyrins (MTPPs) in CO 2 reaction activity is still lacking deep understanding. Here, CO 2 RR mechanism on MTPPs with five different metal centers (M = Fe, Co, Cu, Zn and Ni) are examined by first-principles calculations. The *COOH formation is the rate determined step on the five MTPP structures, and the CoTPP exhibits the best CO 2 RR activity while ZnTPP and NiTPP are the worst, which is also verified by our experiment. The CO 2 RR activity is controlled by adsorption states of intermediates (*CO, *COOH), i.e., chemisorption (e.g., on CoTPP) and physisorption (on ZnTPP and NiTPP) of intermediates will lead to good and poor activity, respectively. The deeper the d- band center of the porphyrin ring complexed metal atom, the weaker bonding of MTPP with CO and COOH. Theoretical calculations and experimental results indicate that MTPPs with Co and Fe centers lead to a reduction in the energy barriers for the two uphill reaction steps in the electrocatalytic CO 2 reduction process, thereby enhancing CO 2 reduction electrocatalytic activity. Faradaic efficiency of CO is correlated with the reaction energy barrier of the first proton-coupled electron reduction process, displaying a strong linear correlation. This work provides a fundamental understanding of MTPPs used as electrocatalysts for CO 2 RR. [ABSTRACT FROM AUTHOR]

The electrochemical carbon dioxide reduction reaction (CO2RR) holds substantial promise for producing high‐value chemicals and fuels, drawing significant attention from both academia and industry. This work proposes an in‐situ electrodeposition method to prepare indium‐doped copper (Cu)‐based catalysts on carbon paper (Cu100Inx−CP, x=3.9, 4.5, 4.8, 5.1, and 7.6, denoting the molar ratio of In to Cu in the catalyst.). The catalysts Cu100Inx−CP were used for CO2RR to produce multi‐carbon (C2+) products. Characterization results showed that In was highly dispersed in the Cu particles at x<5.1. The Cu100In5.1−CP (containing 0.95 wt % In based on Cu) was very efficient for electrocatalytic CO2RR. The in‐situ Raman spectroscopy showed that Cu100In5.1−CP enhanced *CO intermediate adsorption and promoted the production of C2+ products due to the synergistic effect between In and Cu. In doping could suppress HER, enhanced *CO intermediate adsorption, and C−C coupling for the production of C2+ products in CO2RR. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have emerged as a frontier in materials science, offering unique properties due to their atomically thin nature. Among these materials, bismuthene stands out due to its exceptional optical, electronic, and catalytic characteristics. Bismuthene exhibits high charge carrier mobility, stability, and a tunable bandgap (0.3–1.0 eV), making it highly suitable for applications in transistors, spintronics, biomedicine, and photocatalysis. This work explores the so far reported synthesis methods for obtaining 2D bismuthene, including bottom-up approaches like chemical vapor deposition and molecular beam epitaxy, and top-down methods such as liquid-phase exfoliation and mechanical exfoliation. Recent advancements in understanding 2D bismuthene structural phases, electronic properties modulated by spin-orbit coupling, and its potential applications in next-generation photocatalysts are also reviewed. As is retrieved by our literature review, 2D bismuthene shows great promise for addressing significant environmental challenges. For instance, in CO2 reduction, integrating bismuthene into 2D/2D heterostructures enhances electron transfer efficiency, thereby improving selectivity toward valuable products, such as CH4 and formic acid. In organic pollutant degradation, bismuth subcarbonate (Bi2O2CO3) nanosheets, obtained from 2D bismuthene, have demonstrated high photocatalytic degradation of antibiotics under visible light irradiation, due to their increased surface area and efficient generation of reactive species. Moreover, bismuthene-based materials exhibit potential in the photocatalytic water-splitting process for hydrogen production, overcoming issues associated with UV-light dependence and sacrificial agent usage. This review underscores the versatile applications of 2D bismuthene in advancing photocatalytic technologies, offering insights into future research directions and potential industrial applications. [ABSTRACT FROM AUTHOR]

Carbon capture and conversion technology is the main method to reduce carbon dioxide emissions. Porous carbon with large surface area, excellent thermal stability and low-cost has a wide application potential in the field. In this study, nitrogen-doped porous carbon is prepared by hydrothermal carbonization and chemical activation with methyl cellulose and melamine as carbon precursor and nitrogen sources. The effects of activating agent and nitrogen-doping ratios on the structure and electrocatalytic reduction performance are studied. The sample prepared under optimized conditions has a specific surface area of 1417 m2 g−1, total pore volume of 0.9 cm3 g−1, micropore volume of 0.36 cm3 g−1, as well as abundant nitrogen active sites. It exhibits a high CO Faraday efficiency (91%) at overpotential of -0.61 V (vs. RHE), together with a good cycling of long-term stability. [ABSTRACT FROM AUTHOR]

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The carbon dioxide reduction reaction (CO2RR) is one of the most promising solutions for realizing carbon neutralization via converting the emitted CO2 into value‐added chemicals. The CC coupling step for CO dimerization is the rate‐determining step for C2 pathways, which have not been thoroughly investigated. Herein, the direct cation stabilization effects on CO dimerization for *OCCO formation on the representative Cu(100) and Pt(100) surfaces are investigated. Density functional theory calculations show that the presence of alkali metal ions plays a vital role in promoting the coupling of *CO monomers on both metal surfaces, where Cu shows a stronger stabilization effect. More importantly, a strong linear correlation (R2 ≈ 0.9) between the dimer stabilization energy and the reaction energy is revealed for the first time, which is a promising indicator for the selectivity of C2 pathways. Further investigations on electronic structures reveal that the promoting effect on *OCCO formation is strongly related to the negative charges of the molecules, in which the negative charge accumulation is favored by the directional electron transfer due to the chemisorption of *OCCO on Cu(100) surface. This work offers insights into the understanding of CC coupling reactions for CO2RR mechanisms. [ABSTRACT FROM AUTHOR]

To avoid carbonate precipitation for CO2 electrolysis, developing CO2 conversion in an acid electrolyte is viewed as an ultimately challenging technology. In Nature, Xia et al. recently explored a proton-exchange membrane system for reducing CO2 to formic acid with a Pb–PbSO4 composite catalyst derived from waste lead-acid batteries based on the lattice carbon activation mechanism. Up to 93% Faradaic efficiency was realized when formic acid was produced by this technology.

Over the last decade, the CO2 reduction reaction (CO2RR) has been increasingly exploited for the synthesis of high‐value raw materials in gaseous or liquid form, although no examples of CO2 fixation in nanoparticle systems have been demonstrated. Herein, CO2 fixation into solid nanomaterials by laser synthesis and processing of gold colloids in water, traditionally considered a green approach leading to ligand‐free nanoparticles without the formation of by‐products, is reported. If carbon monoxide‐rich gold nanoparticles are observable even after synthesis in deionized water, the presence of CO2 derivatives in alkaline water environment leads to C2 and C3 coupling with the production of carboxylic acids as a typical CO2RR fingerprint. While laser processing of preformed gold colloids is selective for C2 coupling, both C2 and C3 coupling to lactic acid are observed during pulsed laser ablation of a gold target. In the latter case, it is demonstrated that it is possible to synthesize photoluminescent organometallic nanocomposites in the blue spectral region with a quantum yield of about 20% under adequate experimental conditions. In this research, new pathways are offered to be explored in energetics, photonics, catalysis, and synthesis at the nanoscale. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of carbon dioxide (CO2RR) represents a promising strategy for CO2 mitigation, requiring highly efficient catalysts integrated into electrochemical devices to achieve high conversion rates and energy efficiencies for desired products. Establishing a gas diffusion electrode is crucial for practical applications of CO2 electrochemical reduction reactions (CO2RR). This study uses the air-spraying method to immobilise nano-catalysts onto a gas diffusion layer (GDL) with exceptional homogeneity. A composite of copper(I) oxide (Cu2O) and zinc oxide (ZnO) nanoparticles in a 4:1 ratio was deposited onto the GDL. Surface morphology analysis revealed the successful immobilisation of cubic Cu2O and hexagonal wurtzite ZnO with a uniform distribution, indicating potential improvements in CO2RR performance. Contact angle measurements were conducted to assess surface hydrophobicity, comparing pristine GDL with Cu2O/ZnO-based GDL. Although the contact angle on the surface of the Cu2O/ZnO-based GDL slightly reduced from 143.69° to 134.82°, it maintained its hydrophobic nature. This reduction is attributed to Nafion, a binder in the catalyst ink mixture. The sustained high contact angle is crucial for the CO2 reduction reaction process. X-ray diffraction (XRD) diffractograms of Cu2O/ZnO-based GDL were compared with reference Cu2O, ZnO, and bare GDL. The presence of all essential peaks confirms the successful immobilisation. The airspraying technique effectively achieved a favourable distribution of active metals. [ABSTRACT FROM AUTHOR]

Magnetron sputtering (MS) is a very promising approach for electrode preparation due to its versatility, environmental benignity, and sustainability. In particular, by allowing high control of the deposited nanostructures, MS is characterized by: high deposition rates at low temperatures, deposition of complex species just selecting a specific target, high-density films, and outstanding adhesion of the films on supports. In the following study, the preparation by MS, and thus avoiding toxic chemical reagents, of NbRe thin films, for both hydrogen evolution reaction (HER) and CO 2 reduction reaction (CO 2 RR), was reported. Firstly, the electrocatalytic activity of NbRe thin films was tested towards HER showing promising performance: negligible overpotentials and very small Tafel slopes. Secondly, in the context of carbon recycling, and considering renewable sources intermittence, the electrodes were tested towards CO 2 RR, obtaining selectively C3 compounds. Overall, the proposed study aims to contribute to the development of sustainable catalytic electrochemical processes, supporting the ecological transition. • Magnetron sputtering approach for electrode preparation. • Selective H2, C1 and C3 chemicals synthesis from H 2 O and CO 2. • Electrocatalytic activity of NbRe thin films tested towards HER. • Great promise of NbRe film in replacing Pt group species to perform HER and CO 2 RR. [ABSTRACT FROM AUTHOR]

A forward‐bias bipolar membrane (BPM) provides an alkaline cathode condition, which can be beneficial to some electrochemical reactions, such as the CO2 reduction reaction (CO2RR), but the water association (WA) in forward‐bias BPM is not well understood at all. In this study, BPMs are designed with different interfacial polymeric catalysts to investigate the WA reaction under forward‐bias for electrochemical applications. An enhanced current density is observed with added polymeric catalysts (−OH, −O−, −N−, and graphene oxide) compared to the blank control. Temperature‐dependent measurements indicated that the WA in BPM is not kinetically controlled. The in‐plane and through‐plane ions diffusion is investigated, which showed that the WA in BPM is limited mostly by the transport of OH− and, to a lesser degree, H+ at the interface. Molecular dynamic studies presented that the migration rate of OH− at the interface is approximately one order of magnitude lower than that of H+, indicating that the WA is mainly governed by the transport of OH−. Finally, a forward‐bias CO2RR electrolyzer is demonstrated with an Faradaic effeiciency CO (FECO) of 92.2 ± 2.7%. This work provides important fundamental insights into the WA reaction that would enable the use of forward‐bias BPM electrolyzers in future electrochemical applications. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction reaction (eCO2RR) to multicarbon products has been widely recognized for Cu‐based catalysts. However, the structural changes in Cu‐based catalysts during the eCO2RR pose challenges to achieving an in‐depth understanding of the structure–activity relationship, thereby limiting catalyst development. Herein, we employ constant‐potential density functional theory calculations to investigate the sintering process of Cu single atoms of Cu−N−C single‐atom catalysts into clusters under eCO2RR conditions. Systematic constant‐potential ab initio molecular dynamics simulations revealed that the leaching of Cu−(CO)x moieties and subsequent agglomeration into clusters can be facilitated by synergistic adsorption of H and eCO2RR intermediates (e.g. CO). Increasing the Cu2+ concentration or the applied potential can efficiently suppress Cu sintering. Both microkinetic simulations and experimental results further confirm that sintered Cu clusters play a crucial role in generating C2 products. These findings provide significant insights into the dynamic evolution of Cu‐based catalysts and the origin of their activity toward C2 products during the eCO2RR. [ABSTRACT FROM AUTHOR]