The in situ study of surface species and structures of oxide-derived copper catalysts for electrochemical CO2 reduction

Low-coordinated copper facilitates the *CH2CO affinity at enhanced rectifying interface of Cu/Cu2O for efficient CO2-to-multicarbon alcohols conversion

The carbon-carbon coupling at the Cu/Cu2O Schottky interface has been widely recognized as a promising approach for electrocatalytic CO2 conversion into value-added alcohols. However, the limited selectivity of C2+ alcohols persists due to the insufficient control over rectifying interface characteristics required for precise bonding of oxyhydrocarbons. Herein, we present an investigation into the manipulation of the coordination environment of Cu sites through an in-situ electrochemical reconstruction strategy, which indicates that the construction of low-coordinated Cu sites at the Cu/Cu2O interface facilitates the enhanced rectifying interfaces, and induces asymmetric electronic perturbation and faster electron exchange, thereby boosting C-C coupling and bonding oxyhydrocarbons towards the nucleophilic reaction process of *H2CCO-CO. Impressively, the low-coordinated Cu sites at the Cu/Cu2O interface exhibit superior faradic efficiency of 64.15  ±  1.92% and energy efficiency of ~39.32% for C2+ alcohols production, while maintaining stability for over 50 h (faradic efficiency >50%, total current density = 200 mA cm-2) in a flow-cell electrolyzer. Theoretical calculations, operando synchrotron radiation Fourier transform infrared spectroscopy, and Raman experiments decipher that the low-coordinated Cu sites at the Cu/Cu2O interface can enhance the coverage of *CO and adsorption of *CH2CO and CH2CHO, facilitating the formation of C2+ alcohols.

Mechanism of surface oxygen-containing species promoted electrocatalytic CO2 reduction

Oxygen-containing species have been demonstrated to play a key role in facilitating electrocatalytic CO2 reduction (CO2RR), particularly in enhancing the selectivity towards multi-carbon (C2+) products. However, the underlying promotion mechanism is still under debate, which greatly limits the rational optimization of the catalytic performance of CO2RR. Herein, taking CO2 and O2 co-electrolysis over Cu as the prototype, we successfully clarified how O2 boosts CO2RR from a new perspective by employing comprehensive theoretical simulations. Our results demonstrated that O2 in feed gas can be rapidly reduced into *OH, leading to the partial oxidation of Cu surface under reduction conditions. Surface *OH accelerates the formation of quasi-specifically adsorbed K+ due to the electrostatic interaction between *OH and K+ ions, which significantly increases the concentration of K+ near the Cu surface. These quasi-specifically adsorbed K+ ions can not only lower the C-C coupling barriers but also promote the hydrogenation of CO2 to improve the CO yield rate, which are responsible for the remarkably enhanced efficiency of C2+ products. During the whole process, O2 co-electrolysis plays an indispensable role in stabilizing surface *OH. This mechanism can be also adopted to understand the effect of high pH of electrolyte and residual O in oxide-derived Cu (OD-Cu) on the catalytic efficiency towards C2+ products. Therefore, our work provides new insights into strategies for improving C2+ products on the Cu-based catalysts, i.e., maintaining partial oxidation of surface under reduction conditions.

Introduction of a Conductive Layer into Flood-Resistant Gas Diffusion Electrodes with Polymer Substrate for an Efficient Electrochemical CO2 Reduction with Copper Oxide

Conversion of atmospheric carbon dioxide (CO2) into valuable feedstocks is a crucial technology, and electrochemical reduction of CO2 is a promising approach that can provide a useful source of ethylene (C2H4). Gas diffusion electrodes (GDEs) placed at the interface of the CO2 gas and electrolyte can achieve high current density through a sufficient supply of dissolved CO2 to the reaction site, making them indispensable in industrial applications. However, conventional GDEs with carbon substrate have suffered from electrolyte flooding and consequent loss of efficiency, posing an obstacle for practical application. While flood-resistant GDEs with hydrophobic polymer substrate have been proposed recently, only conductive materials can be employed as electrocatalysts because of their insulative properties, despite the high activities of oxide materials such as copper oxide. Here, we introduce an aluminum conductive layer in GDE with polymer substrate to enable the use of electrically resistive catalysts. Cuprous oxide (Cu2O) with silver particles was tested as a model material and has shown prolonged stability (>17 h) with high C2H4 Faraday efficiency (>50%) while suppressing flooding. A thorough characterization revealed that the conductive layer makes Cu2O an efficient electrocatalyst, even on the polymer substrate, by providing sufficient electrons through its conduction path. This research significantly expands the scope of electrode design by enabling the incorporation of a wide range of nonelectrically conductive materials on GDEs with polymer substrate.

Dynamics of bulk and surface oxide evolution in copper foams for electrochemical CO2 reduction

Oxide-derived copper (OD-Cu) materials exhibit extraordinary catalytic activities in the electrochemical carbon dioxide reduction reaction (CO2RR), which likely relates to non-metallic material constituents formed in transitions between the oxidized and the reduced material. In time-resolved operando experiment, we track the structural dynamics of copper oxide reduction and its re-formation separately in the bulk of the catalyst material and at its surface using X-ray absorption spectroscopy and surface-enhanced Raman spectroscopy. Surface-species transformations progress within seconds whereas the subsurface (bulk) processes unfold within minutes. Evidence is presented that electroreduction of OD-Cu foams results in kinetic trapping of subsurface (bulk) oxide species, especially for cycling between strongly oxidizing and reducing potentials. Specific reduction-oxidation protocols may optimize formation of bulk-oxide species and thereby catalytic properties. Together with the Raman-detected surface-adsorbed *OH and C-containing species, the oxide species could collectively facilitate *CO adsorption, resulting an enhanced selectivity towards valuable C2+ products during CO2RR.

Dealloying-derived nanoporous Sn-doped copper with prior selectivity toward formate for CO2 electrochemical reduction

We report nanoporous Cu-Sn catalysts fabricated by chemically dealloying rapid solidified Al-Cu-Sn alloys for the CO2RR. The np-Cu11Sn1 catalyst exhibits a three-dimensional interconnected ligament-channel network structure, which can efficiently convert CO2 to formate with a Faradaic efficiency (FE) of 72.1% at -1.0 V (vs. RHE).

Silver and Copper Nitride Cooperate for CO Electroreduction to Propanol

The need of carbon sources for the chemical industry, alternative to fossil sources, has pointed to CO2 as a possible feedstock. While CO2 electroreduction (CO2 R) allows production of interesting organic compounds, it suffers from large carbon losses, mainly due to carbonate formation. This is why, quite recently, tandem CO2 R, a two-step process, with first CO2 R to CO using a solid oxide electrolysis cell followed by CO electroreduction (COR), has been considered, since no carbon is lost as carbonate in either step. Here we report a novel copper-based catalyst, silver-doped copper nitride, with record selectivity for formation of propanol (Faradaic efficiency: 45 %), an industrially relevant compound, from CO electroreduction in gas-fed flow cells. Selective propanol formation occurs at metallic copper atoms derived from copper nitride and is promoted by silver doping as shown experimentally and computationally. In addition, the selectivity for C2+ liquid products (Faradaic efficiency: 80 %) is among the highest reported so far. These findings open new perspectives regarding the design of catalysts for production of C3 compounds from CO2 .

Electrocatalytic CO2 Reduction to Ethylene: From Advanced Catalyst Design to Industrial Applications

The value-added chemicals, monoxide, methane, ethylene, ethanol, ethane, and so on, can be efficiently generated through the electrochemical CO2 reduction reaction (eCO2 RR) when equipped with suitable catalysts. Among them, ethylene is particularly important as a chemical feedstock for petrochemical manufacture. However, despite its high Faradaic efficiency achievable at relatively low current densities, the substantial enhancement of ethylene selectivity and stability at industrial current densities poses a formidable challenge. To facilitate the industrial implementation of eCO2 RR for ethylene production, it is imperative to identify key strategies and potential solutions through comprehending the recent advancements, remaining challenges, and future directions. Herein, the latest and innovative catalyst design strategies of eCO2 RR to ethylene are summarized and discussed, starting with the properties of catalysts such as morphology, crystalline, oxidation state, defect, composition, and surface engineering. The review subsequently outlines the related important state-of-the-art technologies that are essential in driving forward eCO2 RR to ethylene into practical applications, such as CO2 capture, product separation, and downstream reactions. Finally, a greenhouse model that integrates CO2 capture, conversion, storage, and utilization is proposed to present an ideal perspective direction of eCO2 RR to ethylene.

Gaining Deep Understanding of Electrochemical CO2 RR with In Situ/Operando Techniques

Electrocatalysis for CO2 conversion has been extensively studied to mitigate the energy shortage and environmental issues, which are gaining ever-increasing attention. However, the complicated CO2 reduction process and the dynamic evolution occurring on electrocatalyst surface make it hard to understand the catalytic mechanism. The development of advanced in situ/operando techniques intelligently coupled with electrochemical cells sheds light on the related study via capturing surface atomic rearrangement, tracing chemical state change of catalysts, monitoring the behavior of intermediates and products, and depicting microenvironment near the electrode surface. In this review, fundamentals of the state-of-the-art in situ/operando techniques are clarified first. Case studies on the in situ/operando techniques performed to probe the CO2 reduction reaction processes are then discussed in detail. Finally, conclusions and outlook on this field are presented.

Oxophilicity-Controlled CO2 Electroreduction to C2+ Alcohols over Lewis Acid Metal-Doped Cuδ+ Catalysts

Cu-based electrocatalysts have great potential for facilitating CO2 reduction to produce energy-intensive fuels and chemicals. However, it remains challenging to obtain high product selectivity due to the inevitable strong competition among various pathways. Here, we propose a strategy to regulate the adsorption of oxygen-associated active species on Cu by introducing an oxophilic metal, which can effectively improve the selectivity of C2+ alcohols. Theoretical calculations manifested that doping of Lewis acid metal Al into Cu can affect the C-O bond and Cu-C bond breaking toward the selectively determining intermediate (shared by ethanol and ethylene), thus prioritizing the ethanol pathway. Experimentally, the Al-doped Cu catalyst exhibited an outstanding C2+ Faradaic efficiency (FE) of 84.5% with remarkable stability. In particular, the C2+ alcohol FE could reach 55.2% with a partial current density of 354.2 mA cm-2 and a formation rate of 1066.8 μmol cm-2 h-1. A detailed experimental study revealed that Al doping improved the adsorption strength of active oxygen species on the Cu surface and stabilized the key intermediate *OC2H5, leading to high selectivity toward ethanol. Further investigation showed that this strategy could also be extended to other Lewis acid metals.

Insight on Atomically Dispersed Cu Catalysts for Electrochemical CO2 Reduction

Electrochemical CO2 reduction (ECO2R) with renewable electricity is an advanced carbon conversion technology. At present, copper is the only metal to selectively convert CO2 into multicarbon (C2+) products. Among them, atomically dispersed (AD) Cu catalysts have received great attention due to the relatively single chemical environment, which are able to minimize the negative impact of morphology, valence state, and crystallographic properties, etc. on product selectivity. Furthermore, the completely exposed atomic Cu sites not only provide space and bonding electrons for the adsorption of reactants in favor of better catalytic activity but also provide an ideal platform for studying its reaction mechanism. This review summarizes the recent progress of AD Cu catalysts as a chemically tunable platform for ECO2R, including the atomic Cu sites dynamic evolution, the catalytic performance, and mechanism. Furthermore, the prospects and challenges of AD Cu catalysts for ECO2R are carefully discussed. We sincerely hope that this review can contribute to the rational design of AD Cu catalysts with enhanced performance for ECO2R.

Spatiotemporal Mapping of Local Heterogeneities during Electrochemical Carbon Dioxide Reduction

The activity and selectivity of a copper electrocatalyst during the electrochemical CO₂ reduction reaction (eCO₂RR) are largely dominated by the interplay between local reaction environment, the catalyst surface, and the adsorbed intermediates. In situ characterization studies have revealed many aspects of this intimate relationship between surface reactivity and adsorbed species, but these investigations are often limited by the spatial and temporal resolution of the analytical technique of choice. Here, Raman spectroscopy with both space and time resolution was used to reveal the distribution of adsorbed species and potential reaction intermediates on a copper electrode during eCO₂RR. Principal component analysis (PCA) of the in situ Raman spectra revealed that a working electrocatalyst exhibits spatial heterogeneities in adsorbed species, and that the electrode surface can be divided into CO-dominant (mainly located at dendrite structures) and C-C dominant regions (mainly located at the roughened electrode surface). Our spectral evaluation further showed that in the CO-dominant regions, linear CO was observed (as characterized by a band at ∼2090 cm^-1), accompanied by the more classical Cu-CO bending and stretching vibrations located at ∼280 and ∼360 cm^-1, respectively. In contrast, in the C-C directing region, these three Raman bands are suppressed, while at the same time a band at ∼495 cm^-1 and a broad Cu-CO band at ∼2050 cm^-1 dominate the Raman spectra. Furthermore, PCA revealed that anodization creates more C-C dominant regions, and labeling experiments confirmed that the 495 cm^-1 band originates from the presence of a Cu-C intermediate. These results indicate that a copper electrode at work is very dynamic, thereby clearly displaying spatiotemporal heterogeneities, and that in situ micro-spectroscopic techniques are crucial for understanding the eCO₂RR mechanism of working electrocatalyst materials.

Effects of Iron Species on Low Temperature CO2 Electrolyzers

Electrochemical energy conversion devices are considered key in reducing CO2 emissions and significant efforts are being applied to accelerate device development. Unlike other technologies, low temperature electrolyzers have the ability to directly convert CO2 into a range of value-added chemicals. To make them commercially viable, however, device efficiency and durability must be increased. Although their design is similar to more mature water electrolyzers and fuel cells, new cell concepts and components are needed. Due to the complexity of the system, singular component optimization is common. As a result, the component interplay is often overlooked. The influence of Fe-species clearly shows that the cell must be considered holistically during optimization, to avoid future issues due to component interference or cross-contamination. Fe-impurities are ubiquitous, and their influence on single components is well-researched. The activity of non-noble anodes has been increased through the deliberate addition of iron. At the same time, however, Fe-species accelerate cathode and membrane degradation. Here, we interpret literature on single components to gain an understanding of how Fe-species influence low temperature CO2 electrolyzers holistically. The role of Fe-species serves to highlight the need for considerations regarding component interplay in general.

Oxidation of metallic Cu by supercritical CO2 and control synthesis of amorphous nano-metal catalysts for CO2 electroreduction

Amorphous nano-metal catalysts often exhibit appealing catalytic properties, because the intrinsic linear scaling relationship can be broken. However, accurate control synthesis of amorphous nano-metal catalysts with desired size and morphology is a challenge. In this work, we discover that Cu(0) could be oxidized to amorphous Cu_xO species by supercritical CO₂. The formation process of the amorphous Cu_xO is elucidated with the aid of machine learning. Based on this finding, a method to prepare Cu nanoparticles with an amorphous shell is proposed by supercritical CO₂ treatment followed by electroreduction. The unique feature of this method is that the size of the particles with amorphous shell can be easily controlled because their size depends on that of the original crystal Cu nanoparticles. Moreover, the thickness of the amorphous shell can be easily controlled by CO₂ pressure and/or treatment time. The obtained amorphous Cu shell exhibits high selectivity for C2+ products with the Faradaic efficiency of 84% and current density of 320 mA cm^-2. Especially, the FE of C2+ oxygenates can reach up to 65.3 %, which is different obviously from the crystalline Cu catalysts.

Structural evolution and strain generation of derived-Cu catalysts during CO2 electroreduction

Copper (Cu)-based catalysts generally exhibit high C₂₊ selectivity during the electrochemical CO₂ reduction reaction (CO₂RR). However, the origin of this selectivity and the influence of catalyst precursors on it are not fully understood. We combine operando X-ray diffraction and operando Raman spectroscopy to monitor the structural and compositional evolution of three Cu precursors during the CO₂RR. The results indicate that despite different kinetics, all three precursors are completely reduced to Cu(0) with similar grain sizes (~11 nm), and that oxidized Cu species are not involved in the CO₂RR. Furthermore, Cu(OH)₂- and Cu₂(OH)₂CO₃-derived Cu exhibit considerable tensile strain (0.43%~0.55%), whereas CuO-derived Cu does not. Theoretical calculations suggest that the tensile strain in Cu lattice is conducive to promoting CO₂RR, which is consistent with experimental observations. The high CO₂RR performance of some derived Cu catalysts is attributed to the combined effect of the small grain size and lattice strain, both originating from the in situ electroreduction of precursors. These findings establish correlations between Cu precursors, lattice strains, and catalytic behaviors, demonstrating the unique ability of operando characterization in studying electrochemical processes.

Copper catalysts derived from oxidized precursors typically exhibit high selectivity for CO₂ electroreduction to multicarbon products, yet the influencing factors that control the selectivity need further investigation. Here, the authors reveal that the high selectivity stems from small grain size and lattice strain due to in situ reduction of precursors.

Bicarbonate Rebalances the *COOH/*OCO- Dual Pathways in CO2 Electrocatalytic Reduction: In Situ Surface-Enhanced Raman Spectroscopic Evidence

Understanding the reactive site/CO₂/electrolyte interfacial behaviors is very crucial for the design of an advantageous CO₂ electrocatalytic reduction (CO₂ER) system. One important but unrevealed question is how the CO₂ER process is influenced by the high concentration of HCO₃^-, which is deliberately added as electrolyte or from the inevitable reaction between dissolved CO₂ and OH^-. Here, we provide unambiguous in situ spectroscopic evidence that on Ag-based catalysts, HCO₃^- is apt to facilitate *OCO^- generation and therefore rebalances CO₂ER pathways. By employing an alternative acid electrolyte to restrict the exchange between CO₂ and HCO₃^- and eliminating the effect of solution pH, we reveal that HCO₃^- can decrease the onset potential of *OCO^- and promote further formate production. Theoretical calculations indicate HCO₃^- can stabilize the adsorption of *OCO^- instead of *COOH. The renewed understanding of the role of HCO₃^- could facilitate the judicious selection of electrolytes to regulate the CO₂ER pathway and product distribution.

Catalyst Regeneration via Chemical Oxidation Enables Long-Term Electrochemical Carbon Dioxide Reduction

Electrochemical CO₂ reduction (ECR) with industrially relevant current densities, high product selectivity, and long-term stability has been a long-sought goal. Unfortunately, copper (Cu) catalysts for producing valuable multicarbon (C₂₊) products undergo structural and morphological changes under ECR conditions, especially at high current densities, resulting in a rapid decrease in product selectivity. Herein, we report a catalyst regeneration strategy, one that employs an electrolysis method comprising alternating "on" and "off" operating regimes, to increase the operating stability of a Cu catalyst. We find that it increases operating lifetime many times, maintaining ethylene selectivity ≥40% for at least 200 h of electrolysis in neutral pH media at a current density of 150 mA cm^-2 using a flow cell. We also demonstrate ECR to ethylene at a current density of 1 A cm^-2 with ethylene selectivity ≥40% using a three-dimensional Cu gas diffusion electrode, finding that this system under these conditions is rendered stable for greater than 36 h. This work illustrates that Cu-based catalysts, once they have entered into the state conventionally considered to possess degraded catalytic activity, may be recovered to deliver high C₂₊ selectivity. We present evidence that the combination of short periods of electrolysis, which minimizes the morphological changes during "on" segments, with the progressive chemical oxidation of Cu atoms on the catalyst surface during "off" segments, united with the added effects of washing the accumulated salt and decreasing the catholyte temperature prolong together the catalyst's operating lifetime.

Grain Boundary-Derived Cu+ /Cu0 Interfaces in CuO Nanosheets for Low Overpotential Carbon Dioxide Electroreduction to Ethylene

Electrochemical CO₂ reduction reaction can be used to produce value-added hydrocarbon fuels and chemicals by coupling with clean electrical energy. However, highly active, selective, and energy-efficient CO₂ conversion to multicarbon hydrocarbons, such as C₂ H₄ , remains challenging because of the lack of efficient catalysts. Herein, an ultrasonication-assisted electrodeposition strategy to synthesize CuO nanosheets for low-overpotential CO₂ electroreduction to C₂ H₄ is reported. A high C₂ H₄ Faradaic efficiency of 62.5% is achieved over the CuO nanosheets at a small potential of -0.52 V versus a reversible hydrogen electrode, corresponding to a record high half-cell cathodic energy efficiency of 41%. The selectivity toward C₂ H₄ is maintained for over 60 h of continuous operation. The CuO nanosheets are prone to in situ restructuring during CO₂ reduction, forming abundant grain boundaries (GBs). Stable Cu⁺ /Cu⁰ interfaces are derived from the low-coordinated Cu atoms in the reconstructed GB regions and act as highly active sites for CO₂ reduction at low overpotentials. In situ Raman spectroscopic analysis and density functional theory computation reveal that the Cu⁺ /Cu⁰ interfaces offer high *CO surface coverage and lower the activation energy barrier for *CO dimerization, which, in synergy, facilitates CO₂ reduction to C₂ H₄ at low overpotentials.

Boosting the Productivity of Electrochemical CO2 Reduction to Multi-Carbon Products by Enhancing CO2 Diffusion through a Porous Organic Cage

Electroreduction of CO₂ into valuable fuels and feedstocks offers a promising way for CO₂ utilization. However, the commercialization is limited by the low productivity. Here, we report a strategy to enhance the productivity of CO₂ electroreduction by improving diffusion of CO₂ to the surface of catalysts using porous organic cages (POCs) as an additive. It was noted that the Faradaic efficiency (FE) of C2+ products could reach 76.1 % with a current density of 1.7 A cm^-2 when Cu-nanorod(nr)/CC3 (one of the POCs) was used, which were much higher than that using Cu-nr. Detailed studies demonstrated that the hydrophobic pores of CC3 can adsorb a large amount of CO₂ for the reaction, and the diffusion of CO₂ in the CC3 to the nanocatalyst surface is easier than that in the liquid electrolyte. Thus, more CO₂ molecules make contact with the nanocatalysts in the presence of CC3, enhancing CO₂ reduction and inhibiting generation of H₂ .

Precise real-time quantification for photocatalytic reaction: integration of the sensitivein-situSERS sensor and high-efficiency photocatalyst

Recently,in-situsurface-enhanced Raman spectroscopy (SERS) is gradually becoming an important method for monitoring photocatalytic reaction processes, in which the quantification potential is a vital factor in determining whether this technology can be truly applied in the future. In order to improve the quantification performance ofin-situSERS and explore a precise operando Raman detection for photocatalytic reactions, an architecture of heterostructural Cu₂O/ZnO/Ag nano round brush has been designed and discussed in this work. This structure is an integration of sensitivein-situSERS sensor and high-efficiency photocatalyst, realizing real-time monitoring of photocatalytic reaction in a wide concentration range from 20 to 3 mg l^-1. The coefficient of determination between different detection methods is beyond 0.86 in this range, implying the high-precise quantification of this platform. Comprehensive analysis on structure effect, SERS performance, photocatalytic property, electric filed characteristic, etc were all systematically made and discussed in detail for this platform. This work presents a precise preliminar real-time photocatalytic monitoring usingin-situSERS detection, which is a new attempt and also meaningful reference for otherin-situanalytical technology.

Anode Catalysts in CO2 Electrolysis: Challenges and Untapped Opportunities

The field of electrochemical carbon dioxide reduction has developed rapidly during recent years. At the same time, the role of the anodic half-reaction has received considerably less attention. In this Perspective, we scrutinize the reports on the best-performing CO2 electrolyzer cells from the past 5 years, to shed light on the role of the anodic oxygen evolution catalyst. We analyze how different cell architectures provide different local chemical environments at the anode surface, which in turn determines the pool of applicable anode catalysts. We uncover the factors that led to either a strikingly high current density operation or an exceptionally long lifetime. On the basis of our analysis, we provide a set of criteria that have to be fulfilled by an anode catalyst to achieve high performance. Finally, we provide an outlook on using alternative anode reactions (alcohol oxidation is discussed as an example), resulting in high-value products and higher energy efficiency for the overall process.

Enhancing CO2 electroreduction to CH4 over Cu nanoparticles supported on N-doped carbon

The electroreduction of CO₂ to CH₄ has attracted extensive attention. However, it is still a challenge to achieve high current density and faradaic efficiency (FE) for producing CH₄ because the reaction involves eight electrons and four protons. In this work, we designed Cu nanoparticles supported on N-doped carbon (Cu-np/NC). It was found that the catalyst exhibited outstanding performance for the electroreduction of CO₂ to CH₄. The FE toward CH₄ could be as high as 73.4% with a high current density of 320 mA cm⁻². In addition, the mass activity could reach up to 6.4 A mg_Cu⁻¹. Both experimental and theoretical calculations illustrated that the pyrrolic N in NC could accelerate the hydrogenation of *CO to the *CHO intermediate, resulting in high current density and excellent selectivity for CH₄. This work conducted the first exploration of the effect of N-doped species in composites on the electrocatalytic performance of CO₂ reduction.

The pyrrolic N in Cu-np/NC composites can enhance the activation of H₂O, resulting in excellent selectivity for CH₄ and high current density.

NiFe-CN catalysts derived from Solid-phase Exfoliation of NiFe-Layered Double Hydroxide for CO2 Electroreduction

The development of efficient carbon dioxide reducing reaction (CO2RR) catalysts is one of the practical solutions to environmental problems. Usually metal-doped catalysts were used for CO2RR, but the metal elements...