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• Dendritic In-doped Cu@Cu 2 O catalyst is prepared by co-electrodeposition method. • Doped-In content can tailor Cu+/Cu0 ratio, charge distribution, morphology and ECSA. • Cu+/Cu0 ratio plays a vital role on enhancing FE CO and partial current density at low In doping. • 3.7% In-Cu sample shows the highest FE CO of 87.6 ± 2.2 % and j CO of 9.7 ± 1.04 mA cm -2. Element doping is an effective strategy to enhance the selectivity of electrochemical carbon dioxide reduction. In this work, a dendritic core-shell In-doped Cu@Cu 2 O catalyst is prepared by co-electrodeposition method on carbon fiber paper for selective electroreduction of CO 2 to CO. Faradaic efficiency of producing CO over this dendritic In-doped Cu@Cu 2 O reaches 87.6 ± 2.2% with total current density of 11.1 ± 0.85 mA cm−2 at −0.8 V vs RHE, which outperforms most of the reported Cu-based electrocatalysts. The excellent performance is mainly derived from charge re-distribution and the enhanced intrinsic activity due to the formation of In-doped Cu 2 O layer. Meanwhile, the Cu+/Cu0 can be adjusted by tailoring the doped-In content. The relatively high ECSA and small charge transfer resistance are also conducive to improve the selectivity and activity. The oxyphilic In metal incorporated into the copper lattice can well stabilize the intermediate *COOH through enhancing interaction with O-ends of *COOH. This work provides a facile approach and a deep insight on design and synthesis of high efficiency hybrid electrocatalysts. [ABSTRACT FROM AUTHOR]

Renewable energy resources (wind, solar) are unpredictable, so it is wise to store the electricity they generate in an energy carrier X. Various PtX (power to useful energy-intensive raw material such as hydrogen, synthetic natural gas, fuel) applications have been proposed. At the heart of our work is widely used idea to convert residual CO2 from biogas plant into higher hydrocarbons using electricity from renewables (e.g., sun, wind, hydro). The specific goal is to produce ethylene-highly demanded hydrocarbon in plastics industry. The process itself is realised on electrocatalytic carbon/copper cathode which must be selective to reaction: 2CO2 + 12e− + 12H+→C2H4 + 4H2O. We propose a bottom-up approach to build catalyst from the smallest particles-graphene sheet stacks (GSS) coated with metallic copper nanocrystals. Composite GSS-Cu structure functions as a CO2 and proton absorber, facilitating hydrogenation and carbon–carbon coupling reactions on Cu-nanocluster/GSS for the formation of C2H4. In our design electrocatalytic electrode is made from nitrogen-doped graphene sheet stacks coated with copper nanostructures. The N-GSSitself can be drop-casted or electrophoretically incorporated onto the carbon paper and gas diffusion electrode. Electrochemical deposition method was recognized as successful and most promising to grow Cu nanocrystals on N-GSS incorporated in conducting carbon substrate. Gaseous products from CO2 electro-catalytic reformation on the cathode were investigated by mass-spectrometer but the electrode surface was analysed by SEM/EDS and XRD methods. [ABSTRACT FROM AUTHOR]

The development of efficient carbon dioxide reduction reaction (CO2RR) catalysts is one of the practical solutions to the current environmental problems. Usually, metal-doped catalysts are used for the CO2RR, but the metal elements can easily aggregate, resulting in a reduction in the catalytic performance. In this study, NiFe-LDH was exfoliated to single layer by a solid-phase exfoliation strategy, wherein Ni and Fe were doped on the char material owing to the pyrolysis of the solid-phase exfoliation agent, and the NiFe-CN catalyst with a gauzy and porous structure was obtained. The catalyst possessed excellent catalytic performance; particularly, when the mass fraction of NiFe-LDH was 1 wt%, the prepared catalyst (NiFe-CN-1) showed a faradaic efficiency of 93.5% for the reduction of CO2 to CO at −0.8 V (vs. reversible hydrogen electrode (RHE)) with a CO current density of 10.4 mA cm−2, which was due to the sufficient exposure of active sites and efficient proton transfer channels of NiFe-CN. This strategy provides a new idea to easily mass produce CO2RR electrocatalysts in an environmentally benign way. [ABSTRACT FROM AUTHOR]

In recent decades, significant progress has been achieved in rational developments of electrocatalysts through constructing novel atomistic structures and modulating catalytic surface topography, realizing substantial enhancement in electrocatalytic activities. Numerous advanced catalysts were developed for electrochemical energy conversion, exhibiting low overpotential, high intrinsic activity, and selectivity. Yet, maintaining the high catalytic performance under working conditions with high polarization and vigorous microkinetics that induce intensive degradation of surface nanostructures presents a significant challenge for commercial applications. Recently, advanced operando and computational techniques have provided comprehensive mechanistic insights into the degradation of surficial functional structures. Additionally, various innovative strategies have been devised and proven effective in sustaining electrocatalytic activity under harsh operating conditions. This review aims to discuss the most recent understanding of the degradation microkinetics of catalysts across an entire range of anodic to cathodic polarizations, encompassing processes such as oxygen evolution and reduction, hydrogen reduction, and carbon dioxide reduction. Subsequently, innovative strategies adopted to stabilize the materials' structure and activity are highlighted with an in-depth discussion of the underlying rationale. Finally, we present conclusions and perspectives regarding future research and development. By identifying the research gaps, this review aims to inspire further exploration of surface degradation mechanisms and rational design of durable electrocatalysts, ultimately contributing to the large-scale utilization of electroconversion technologies. [ABSTRACT FROM AUTHOR]

The design of highly stable, effective, and selective electrocatalysts is essential for electrochemical reduction of carbon dioxide (CO2). Here, on the basis of density functional theory (DFT) computations, the reaction mechanisms of the reduction of CO2 over a series of bis(iminothiolato)metal (TMIT, TM = Mn, Fe, Co, Ni, Cu, Ru, Rh, and Pd) were studied. It is found that the CO2RR activity of TMIT depends on the choice of the central metal atom. Our results demonstrated that HCOOH is the main product for TMIT (TM = Mn, Fe, Co, Ni, Cu, Pd). Among them, MnIT and FeIT are promising CO2RR catalysts for the HCOOH production due to the good selectivity and catalytic activity with the low overpotential of 0.34 V and 0.35 V, respectively. For RuIT and RhIT, the main product is CO, and the strong adsorption of CO on the catalyst surfaces would poison the catalysts. This makes RhIT and RuIT not good CO2RR catalysts. We anticipate that this work may shed new light on the development of high-performance metal organic framework (MOF)-based electrocatalysts. [ABSTRACT FROM AUTHOR]

Catalysis plays a crucial role in all the major applications and challenges in the environment, including energy generation and environmental remediation. Although photocatalysts and electrocatalysts are useful in addressing energy and environmental issues, they have some major drawbacks, such as low efficiency and easy charge recombination which limits their applications. Hence, it is imperative to design and explore new catalytic techniques that include non‐photoresponsive catalysts. In this review, the detailed possibilities, characteristics and prospects of non‐photoresponsive catalysts, such as piezocatalysts, thermocatalysts, pyrocatalysts, and tribocatalysts along with hybrid catalysts are described. The overall mechanism of each catalytic technique and its applications in different fields such as energy generation, environmental remediation, and carbon dioxide reduction are discussed. [ABSTRACT FROM AUTHOR]

Single-atom catalysts (SACs) have emerged as well-known catalysts in renewable energy storage and conversion systems. Several supports have been developed for stabilizing single-atom catalytic sites, e.g., organic-, metal-, and carbonaceous matrices. Noticeably, the metal species and their local atomic coordination environments have a strong influence on the electrocatalytic capabilities of metal atom active centers. In particular, asymmetric atom electrocatalysts exhibit unique properties and an unexpected carbon dioxide reduction reaction (CO2RR) performance different from those of traditional metal-N4 sites. This review summarizes the recent development of asymmetric atom sites for the CO2RR with emphasis on the coordination structure regulation strategies and their effects on CO2RR performance. Ultimately, several scientific possibilities are proffered with the aim of further expanding and deepening the advancement of asymmetric atom electrocatalysts for the CO2RR. [ABSTRACT FROM AUTHOR]

The conventional environment polluting energy sources and the continuous growing energy demand compelled researchers to find alternative energy sources. Therefore, in recent years, extensive research has been carried out in synthesizing catalysts for energy conversion applications. This review focuses on the application of various electrodeposition methods in the synthesis of energy‐related electrocatalyst and briefly discusses different electrocatalyst characterization techniques. Further, the influence of various parameters on the electrocatalyst activity and stability is highlighted. Electrocatalyst application in clean energy conversion reactions, such as the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, carbon dioxide reduction reaction, nitrogen reduction reaction along with the metal‐air/CO2 battery, are reviewed. Finally, the comparative experimental data are provided as a reference to synthesize the next‐generation electrodeposited electrocatalyst in clean energy conversions and beyond. [ABSTRACT FROM AUTHOR]

Highlights: The main construction methods of carbon-based nanomaterials (CBN) with different defects are systematically introduced. The structure–activity relationship of defective carbon-based catalysts in electrocatalytic carbon dioxide reduction (ECR) reaction is mainly reviewed. Challenges and opportunities of high-performance defective CBN in ECR and the possible solutions in the future are discussed. Electrocatalytic carbon dioxide (CO2) reduction (ECR) has become one of the main methods to close the broken carbon cycle and temporarily store renewable energy, but there are still some problems such as poor stability, low activity, and selectivity. While the most promising strategy to improve ECR activity is to develop electrocatalysts with low cost, high activity, and long-term stability. Recently, defective carbon-based nanomaterials have attracted extensive attention due to the unbalanced electron distribution and electronic structural distortion caused by the defects on the carbon materials. Here, the present review mainly summarizes the latest research progress of the construction of the diverse types of defects (intrinsic carbon defects, heteroatom doping defects, metal atomic sites, and edges detects) for carbon materials in ECR, and unveil the structure–activity relationship and its catalytic mechanism. The current challenges and opportunities faced by high-performance carbon materials in ECR are discussed, as well as possible future solutions. It can be believed that this review can provide some inspiration for the future of development of high-performance ECR catalysts. [ABSTRACT FROM AUTHOR]

Development of efficient catalysts for selective electroreduction of CO2 to high-value products is essential for the deployment of carbon utilization technologies. Here we present a scalable method for preparing Cu electrocatalysts that favor CO2 conversion to C2+ products with faradaic efficiencies up to 72%. Grazing-incidence X-ray diffraction data confirms that anodic halogenation of electropolished Cu foils in aqueous solutions of KCl, KBr, or KI creates surfaces of CuCl, CuBr, or CuI, respectively. Scanning electron microscopy and energy dispersive X-ray spectroscopy studies show that significant changes to the morphology of Cu occur during anodic halogenation and subsequent oxide-formation and reduction, resulting in catalysts with a high density of defect sites but relatively low roughness. This work shows that efficient conversion of CO2 to C2+ products requires a Cu catalyst with a high density of defect sites that promote adsorption of carbon intermediates and C–C coupling reactions while minimizing roughness. Selective reduction of carbon dioxide to high-value products is key for advancing carbon capture and utilization technologies. Here the authors prepare a copper catalyst for electrocatalytic conversion of carbon dioxide to C2+ products with enhanced selectivity that is attributed to a high density of surface defects. [ABSTRACT FROM AUTHOR]

The electrochemical conversion of carbon dioxide (CO2) into value‐added chemicals is regarded as one of the promising routes to mitigate CO2 emission. A nitrogen‐doped carbon‐supported palladium (Pd) single‐atom catalyst that can catalyze CO2 into CO with far higher mass activity than its Pd nanoparticle counterpart, for example, 373.0 and 28.5 mA mg−1Pd, respectively, at −0.8 V versus reversible hydrogen electrode, is reported. A combination of in situ X‐ray characterization and density functional theory (DFT) calculation reveals that the PdN4 site is the most likely active center for CO production without the formation of palladium hydride (PdH), which is essential for typical Pd nanoparticle catalysts. Furthermore, the well‐dispersed PdN4 single‐atom site facilitates the stabilization of the adsorbed CO2 intermediate, thereby enhancing electrocatalytic CO2 reduction capability at low overpotentials. This work provides important insights into the structure‐activity relationship for single‐atom based electrocatalysts. [ABSTRACT FROM AUTHOR]

It is of paramount importance to design and develop highly active and selective electrocatalysts for the CO2 reduction reaction. Herein, we obtained bismuth-based catalysts consisting of oxidized Bi2O2CO3 and metallic Bi featuring local shortened inter-layer Bi–Bi bonds from in situ reduction of bismuth oxyiodide (BiOI) microflowers, which showed over 90% formate faradaic efficiency in a wide negative potential region. [ABSTRACT FROM AUTHOR]

Abstract: Electrochemical carbon dioxide (CO2) reduction can produce valuable carbonaceous compounds that are in significant demand, due to its ability to decrease the accumulated atmospheric CO2 and improve the intermittent nature of renewable energy sources. Considering the sluggish kinetics of CO2 reduction reaction, the multielectron–proton transfer process, and the inevitable mixed reduction products, designing efficient and robust electrocatalysts that benefit from the structure–activity relationship is the focus to promote CO2 conversion. In this review, various metal‐based materials are first classified and discussed in terms of their structural and elemental compositions for catalytic behaviors. Afterward, the most intrinsic microstructural/electronic effects as well as the influence of compositional alteration on the catalyst activity, selectivity, and stability are summarized. Additionally, recent attempts to develop the assigned electrochemical cells are surveyed and described from a technological point of view. [ABSTRACT FROM AUTHOR]

The copper-based catalyst is considered to be the only catalyst for electrochemical carbon dioxide reduction to produce a variety of hydrocarbons, but its low selectivity and low current density to C2 products restrict its development. Herein, a core-shell xZnO@yCu2O catalysts for electrochemical CO2 reduction was fabricated via a two-step route. The high selectivity of C2 products of 49.8% on ZnO@4Cu2O (ethylene 33.5%, ethanol 16.3%) with an excellent total current density of 140.1 mA cm−2 was achieved over this core-shell structure catalyst in a flow cell, in which the C2 selectivity was twice that of Cu2O. The high electrochemical activity for ECR to C2 products was attributed to the synergetic effects of the ZnO core and Cu2O shell, which not only enhanced the selectivity of the coordinating electron, improved the HER overpotential, and fastened the electron transfer, but also promoted the multielectron involved kinetics for ethylene and ethanol production. This work provides some new insights into the design of highly efficient Cu-based electrocatalysts for enhancing the selectivity of electrochemical CO2 reduction to produce high-value C2 products. [ABSTRACT FROM AUTHOR]