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Results for “Hydrogen evolution suppression”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

High efficiency iron electrode and additives for use in rechargeable iron-based batteries

An iron electrode and a method of manufacturing an iron electrode for use in an iron-based rechargeable battery are disclosed. In one embodiment, the iron electrode includes carbonyl iron powder and one of a metal sulfide additive or metal oxide additive selected from the group of metals consisting of bismuth, lead, mercury, indium, gallium, and tin for suppressing hydrogen evolution at the iron electrode during charging of the iron-based rechargeable battery. An iron-air rechargeable battery including an iron electrode comprising carbonyl iron is also disclosed, as is an iron-air battery wherein at least one of the iron electrode and the electrolyte includes an organosulfur additive.

25 ENERGY STORAGE↗
DOE OSTI2026

Modulating Cu electrode microenvironments with MOF coatings: insights from molecular dynamics and electrochemical experiments of CO reduction

Metal-organic frameworks (MOFs) present a compelling strategy for tuning electrochemical interfaces by reshaping interfacial solvent structure. In this study, we examine how MOF coatings influence the microenvironment at copper electrodes during the CO electroreduction reaction (CORR) using a combined approach of molecular dynamics (MD) simulations and electrochemical experiments. Two MOFs, NU-901 and ZIF-8, are selected to explore the impact of pore size and channel hydrophobicity on electrochemical activity and interfacial concentration in acetonitrile (ACN) and dimethyl sulfoxide (DMSO) electrolytes. Electrochemical measurements reveal that MOF@Cu electrodes exhibit lower Faradaic efficiencies for CO hydrogenation products (ethylene and methane) compared to bare copper but have dramatic impacts on the interfacial microenvironment. NU-901, with its larger pores and strong interactions with DMSO, traps DMSO molecules and enhances CO coordination in DMSO but suppresses CORR selectivity in favor of the hydrogen evolution reaction (HER). ZIF-8, with smaller pores and hydrophobic channels, limits the interfacial water concentration, and, in ACN, promotes CO coordination. The simulations provide insights into how MOFs can act as physical modulators of reactant delivery and interfacial structure to control electrochemical microenvironments. This work highlights the value of molecular dynamics in uncovering how structural features of MOFs influence interfacial phenomena, even when catalytic performance is not directly improved.

Copper electrode microenvironments↗
DOE OSTI2017

Electrochemical CO 2 Reduction over Compressively Strained CuAg Surface Alloys with Enhanced Multi-Carbon Oxygenate Selectivity

The electrochemical reduction of carbon dioxide using renewably generated electricity offers a potential means for producing fuels and chemicals in a sustainable manner. To date, copper has been found to be the most effective catalyst for electrochemically reducing carbon dioxide to products such as methane, ethene, and ethanol. Unfortunately, the current efficiency of the process is limited by competition with the relatively facile hydrogen evolution reaction. Since multi-carbon products are more valuable precursors to chemicals and fuels than methane, there is considerable interest in modifying copper to enhance the multi-carbon product selectivity. In this paper, we report our investigations of electrochemical carbon dioxide reduction over CuAg bimetallic electrodes and surface alloys, which we find to be more selective for the formation of multi-carbon products than pure copper. This selectivity enhancement is a result of the selective suppression of hydrogen evolution, which occurs due to compressive strain induced by the formation of a CuAg surface alloy. Furthermore, we report that these bimetallic electrocatalysts exhibit an unusually high selectivity for the formation of multi-carbon carbonyl-containing products, which we hypothesize to be the consequence of a reduced coverage of adsorbed hydrogen and the reduced oxophilicity of the compressively strained copper. Thus and finally, we show that promoting copper surface with small amounts of Ag is a promising means for improving the multi-carbon oxygenated product selectivity of copper during electrochemical CO 2 reduction.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Doping palladium with tellurium for the highly selective electrocatalytic reduction of aqueous CO 2 to CO

Designing highly selective and energy-efficient electrocatalysts to minimize the competitive hydrogen evolution reaction in the electrochemical reduction of aqueous CO 2 remains a challenge. In this study, we report that doping Pd with a small amount of Te could selectively convert CO 2 to CO with a low overpotential. The PdTe/few-layer graphene (FLG) catalyst with a Pd/Te molar ratio of 1 : 0.05 displayed a maximum CO faradaic efficiency of about 90% at –0.8 V ( vs. a reversible hydrogen electrode, RHE), CO partial current density of 4.4 mA cm –2 , and CO formation turnover frequency of 0.14 s –1 at –1.0 V ( vs. a RHE), which were 3.7-, 4.3-, and 10-fold higher than those of a Pd/FLG catalyst, respectively. Density functional calculations showed that Te adatoms preferentially bind at the terrace sites of Pd, thereby suppressing undesired hydrogen evolution, whereas CO 2 adsorption and activation occurred on the high index sites of Pd to produce CO.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Pseudocapacitance Facilitates the Electrocatalytic Reduction of Carbon Dioxide

Electroreduction of CO 2 to value-added products is a promising strategy for CO 2 reuse, where copper has a unique ability to produce oxygenates and C 2+ products. Unfortunately, the electronic factors making copper so unique are unknown, which limits the ability to design improved catalysts. By combining in situ surface-sensitive X-ray resonant photoelectron spectroscopy with density functional theory calculations, the complex electronic structure of copper is uncovered during the electrocatalytic reduction of CO 2 . It is found that the pseudocapacitive charging of copper, produced by the incorporation of protons and electrons into the subsurface, facilitates the activation of CO 2 , while simultaneously increasing the barrier for H-H coupling. The net result is that cathodic pseudocapacitive charge suppresses the hydrogen evolution reaction and promotes the production of hydrocarbons and oxygenated products on copper. These results represent a new paradigm in the understanding of CO 2 reduction, highlighting the key role of pseudocapacitive charge in the reaction.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Surface Oxide-Derived Nanoporous Gold Catalysts for Electrochemical CO 2 -to-CO Reduction

Electrochemical CO 2 reduction (ECR) has become a viable option as the cost of renewable energy continues to decrease. One of the major obstacles that prevents its widespread use is the lack of efficient ECR catalysts due to our only slowly emerging understanding of catalyst design. Here, we report on a surface oxide-derived nanoporous gold catalyst prepared by one-step electrochemical dealloying that shows an extremely low overpotential (Faradaic efficiency for CO exceeds 90%) of 0.185 V (–0.3 V vs RHE) for CO 2 -to-CO conversion in 0.1 M KHCO 3 solution. Here, we demonstrate that surface oxide-derived nanoporous gold shows improved ECR performance with higher Faradaic efficiency compared to clean nanoporous gold which is the consequence of its smaller overpotential for CO 2 -to-CO reduction and simultaneous suppression of hydrogen evolution.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

Intrinsically Conductive {pi}‑d Conjugated Layers with Co–N4 Active Sites for Efficient Nitrate Electrocatalysis and Zinc-Nitrate Batteries

Electrochemical synthesis of ammonia from nitrate has been extensively investigated as a potential alternative to the energy-intensive Haber-Bosch process. This approach not only operates under ambient conditions but also simultaneously removes nitrate contaminants while producing ammonia as a value-added product. However, the ongoing quest lies in designing an efficient electrocatalyst that achieves a high ammonia yield rate, high selectivity, and long-term stability. Herein, we report the outstanding performance of a Co–N4 coordinated π-d layered Co3(HITP)2 (HITP = 2,3,6,7,10,11-hexaiminotriphenylene) in nitrate electrocatalysis. The unique combination of abundant Co–N4 active sites and superior electrical conductivity enables significant electrocatalytic activity, delivering a maximum ammonia yield rate of 56.8 mg cm–2 h–1 at −0.8 V vs RHE and a Faradaic efficiency of ∼91% at −0.4 V vs RHE. Mechanistic analysis reveals that alkaline conditions accelerate water dissociation to generate adsorbed hydrogen intermediates (H*), which are utilized by Co–N4 sites to drive the stepwise hydrogenation of nitrate to ammonia while suppressing competing hydrogen evolution reaction (HER) pathways. Furthermore, integration of this catalyst into a zinc-nitrate battery resulted in a maximum power density of 5.3 mW cm–2 and an open-circuit potential of ∼1.45 V. These results highlight the potential of π-d conjugated Co–N4 materials as an efficient catalyst for both environmental remediation and energy conversion.

Namvar, shahrirar↗
DOE OSTI2022

Continuum Model to Define the Chemistry and Mass Transfer in a Bicarbonate Electrolyzer

Bicarbonate electrolyzers are devices designed to convert CO 2 captured from point sources or the atmosphere into chemicals and fuels without needing to first isolate pure CO 2 gas. In this work, we report here an experimentally validated model that quantifies the reaction chemistry and mass transfer processes within the catalyst layer and cation exchange membrane layer of a bicarbonate electrolyzer. Our results demonstrate that two distinct chemical microenvironments are key to forming CO at high rates: an acidic membrane layer that promotes in situ CO 2 formation and a basic catalyst layer that suppresses the hydrogen evolution reaction. We show that the rate of CO product formation can be increased by modulating the catalyst and membrane layer properties to increase the rate of in situ CO 2 generation and transport to the cathode. These insights serve to inform the design of bicarbonate and BPM-based CO 2 electrolyzers while demonstrating the value of modeling for resolving rate-determining processes in electrochemical systems.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Surface Composition Impacts Selectivity of ZnTe Photocathodes in Photoelectrochemical CO 2 Reduction Reaction

Light-driven reduction of CO 2 into chemicals using a photoelectrochemical (PEC) approach is considered as a promising way to meet the carbon neutral target. The very top surface of the photoelectrode and semiconductor/electrolyte interface plays a pivotal role in defining the performance for PEC CO 2 reduction. However, such impact remains poorly understood. Here, we report an electrodeposition-annealing route for tailoring surface composition of ZnTe photocathodes. Our work demonstrates that a Zn-rich surface on the ZnTe photocathode is essential to impact the CO 2 reduction activity and selectivity. In particular, the Zn-rich surface not only facilitated the interfacial charge carrier transfer, but also acted as electrocatalyst for boosting carbon product selectivity and suppressing the hydrogen evolution reaction. This work provides a new avenue to optimize the photocathode, as well as improvement of the CO 2 RR performance.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Plasma-Assisted Surface Nitridation of Proton Intercalatable WO 3 for Efficient Electrocatalytic Ammonia Synthesis

Electrocatalytic nitrogen reduction (eNRR) offers a green pathway for the production of NH 3 from N 2 and H 2 O under ambient conditions. Transition metal oxynitrides (TMO x N y ) are among the most promising catalysts but face challenges in achieving a high yield and faradaic efficiency (FE). This work develops a hybrid WO x N y /WO 3 catalyst with a unique heterogeneous interfacial complexion (HIC) structure. This design enables in situ generation and delivery of highly active hydrogen atoms (H*) in acidic electrolytes, promoting nitrogen hydrogenation and the formation of nitrogen vacancies (Nv) on the WO x N y surface. This significantly enhances the selectivity of eNRR for NH 3 synthesis while suppressing the hydrogen evolution reaction (HER). A simple two-step fabrication process─microwave hydrothermal growth followed by plasma-assisted surface nitridation─was developed to fabricate the designed catalyst electrode, achieving an NH 3 yield of 3.2 × 10 –10 mol·cm –2 ·s –1 with 40.1% FE, outperforming most TMN/TMO x N y electrocatalysts. Multiple control experiments confirm that the eNRR follows an HIC-enhanced Mars–van Krevelen (MvK) mechanism.

Catalysts↗
DOE OSTI2019

Electroreduction of Carbon Dioxide into Selective Hydrocarbons at Low Overpotential Using Isomorphic Atomic Substitution in Copper Oxide

The conversion of carbon dioxide into selective hydrocarbons is vital for green energy generation. Due to the chemical instability and lower activity, environmentally stable transition metal oxides (e.g., CuO) are unpopular for CO 2 electroreduction catalysis. Here, we demonstrate substitution of Cu with an isomorphic atom, i.e., Ni, in CuO and utilize it for improving the hydrocarbon selectivity by 4 times as compared to that of pristine CuO. Hydrocarbon formation is achieved at the lowest possible applied potential (-0.2 V, reversible hydrogen electrode). This gives the overpotential of about 0.37 V for methane and 0.28 V for ethylene, the lowest ever reported. Employing the ionic interaction between Ni and Cu, this catalyst suppresses the hydrogen evolution reaction to improve the hydrocarbon selectivity prominently. It is observed that current normalized by the Brunauer–Emmett–Teller surface area gives 15–20 times enhancement in the case of Ni-substituted CuO compared to undoped CuO. The in situ experiments indicate that Ni-doped CuO prefers CO pathways compared to formate, resulting into high hydrocarbon selectivity. The experimental observation is further supported by density functional theory studies, which reveal that the Ni-doped CuO catalyst has a higher limiting potential for CO 2 electroreduction to CH 4 due to the stabilization of the CH 2 O intermediate on the Cu 0.9375 Ni 0.0625 O surface rather than the CHO intermediate, in comparison to the pristine CuO surface.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

N and OH-Immobilized Cu 3 Clusters In Situ Reconstructed from Single-Metal Sites for Efficient CO 2 Electromethanation in Bicontinuous Mesochannels

Cu-based catalysts hold promise for electrifying CO 2 to produce methane, an extensively used fuel. However, the activity and selectivity remain insufficient due to the lack of catalyst design principles to steer complex CO 2 reduction pathways. Herein, we develop a concept to design carbon-supported Cu catalysts by regulating Cu active sites’ atomic-scale structures and engineering the carbon support’s mesoscale architecture. This aims to provide a favorable local reaction microenvironment for a selective CO 2 reduction pathway to methane. In situ X-ray absorption and Raman spectroscopy analyses reveal the dynamic reconstruction of nitrogen and hydroxyl-immobilized Cu 3 (N,OH-Cu 3 ) clusters derived from atomically dispersed Cu–N 3 sites under realistic CO 2 reduction conditions. The N,OH-Cu 3 sites possess moderate *CO adsorption affinity and a low barrier for *CO hydrogenation, enabling intrinsically selective CO 2 -to-CH 4 reduction compared to the C–C coupling with a high energy barrier. Importantly, a block copolymer-derived carbon fiber support with interconnected mesopores is constructed. The unique long-range mesochannels offer an H 2 O-deficient microenvironment and prolong the transport path for the CO intermediate, which could suppress the hydrogen evolution reaction and favor deep CO 2 reduction toward methane formation. Thus, the newly developed catalyst consisting of in situ constructed N,OH-Cu 3 active sites embedded into bicontinuous carbon mesochannels achieved an unprecedented Faradaic efficiency of 74.2% for the CO 2 reduction to methane at an industry-level current density of 300 mA cm –2 . In conclusion, this work explores effective concepts for steering desirable reaction pathways in complex interfacial catalytic systems via modulating active site structures at the atomic level and engineering pore architectures of supports on the mesoscale to create favorable microenvironments.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Efficient electrocatalytic valorization of chlorinated organic water pollutant to ethylene

Electrochemistry can provide an efficient and sustainable way to treat environmental waters polluted by chlorinated organic compounds. However, the electrochemical valorization of 1,2-dichloroethane (DCA) is currently challenged by the lack of a catalyst that can selectively convert DCA in aqueous solutions into ethylene. Here, in this work, we report a catalyst comprising cobalt phthalocyanine molecules assembled on multiwalled carbon nanotubes that can electrochemically decompose aqueous DCA with high current and energy efficiencies. Ethylene is produced at high rates with unprecedented ~100% Faradaic efficiency across wide electrode potential and reactant concentration ranges. Kinetic studies and density functional theory calculations reveal that the rate-determining step is the first C–Cl bond breaking, which does not involve protons—a key mechanistic feature that enables cobalt phthalocyanine/carbon nanotube to efficiently catalyse DCA dechlorination and suppress the hydrogen evolution reaction. The nanotubular structure of the catalyst enables us to shape it into a flow-through electrified membrane, which we have used to demonstrate >95% DCA removal from simulated water samples with environmentally relevant DCA and electrolyte concentrations.

Choi, Chungseok↗
DOE OSTI2026

First-Principles Insights into Proton-Coupled Electron Transfer versus Hydrogen Evolution Reaction Selectivity from a Base-Appended Cobaltocene Mediator

Performing selective proton-coupled electron transfer (PCET) to substrates such as N 2 , CO 2 , and unsaturated organic molecules under electrochemical conditions requires the suppression of the competing hydrogen evolution reaction (HER). To address this challenge, our laboratory previously demonstrated a PCET mediator strategy using a dimethylaniline-appended cobaltocene complex, [(CpCoCp NMe2 )H] + , which performs selective reductive chemistry while suppressing the HER. However, the origin of the suppressed, yet still observable, HER has not been thoroughly established. In this work, we perform density functional theory (DFT) calculations to elucidate the HER mechanism involving this redox mediator and to provide atomistic insights into the bifurcation between the PCET and HER pathways. We find that protonation of the aniline moiety to form [CpCoCp NMe2H ] + is more favorable, both kinetically and thermodynamically, than formation of the ring-protonated species [(CpCo(Cp-H) NMe2 )] + . Furthermore, PCET to acetophenone is energetically more favorable via [CpCoCp NMe2H ] + than via [(CpCo(Cp-H) NMe2 )] +1/0 . In contrast, the most favorable HER pathway involves the ring-protonated Co(I) species. These results offer mechanistic insights into HER versus PCET bifurcation and establish guiding principles for designing PCET mediators for selective electroreductive transformations.

evolution reactions↗
DOE OSTI2022

Biomimetic Metal-Free Hydride Donor Catalysts for CO 2 Reduction

The catalytic reduction of carbon dioxide to fuels and value-added chemicals is of significance for the development of carbon recycling technologies. One of the main challenges associated with catalytic CO 2 reduction is product selectivity: the formation of carbon monoxide, molecular hydrogen, formate, methanol, and other products occurs with similar thermodynamic driving forces, making it difficult to selectively reduce CO 2 to the target product. Significant scientific effort has been aimed at the development of catalysts that can suppress the undesired hydrogen evolution reaction and direct the reaction toward the selective formation of the desired products, which are easy to handle and store. Inspired by natural photosynthesis, where the CO 2 reduction is achieved using NADPH cofactors in the Calvin cycle, in this study we explore biomimetic metal-free hydride donors as catalysts for the selective reduction of CO 2 to formate. Here, we outline our recent findings on the thermodynamic and kinetic parameters that control the hydride transfer from metal-free hydrides to CO 2 . By experimentally measuring and theoretically calculating the thermodynamic hydricities of a range of metal-free hydride donors, we derive structural and electronic factors that affect their hydride-donating abilities. Two dominant factors that contribute to the stronger hydride donors are identified to be (i) the stabilization of the positive charge formed upon HT via aromatization or by the presence of electron-donating groups and (ii) the destabilization of hydride donors through the anomeric effect or in the presence of significant structural constrains in the hydride molecule. Hydride donors with appropriate thermodynamic hydricities were reacted with CO 2 , and the formation of the formate ion (the first reduction step in CO 2 reduction to methanol) was confirmed experimentally, providing an important proof of principle that organocatalytic CO 2 reduction is feasible. The kinetics of hydride transfer to CO 2 were found to be slow, and the sluggish kinetics were assigned in part to the large self-exchange reorganization energy associated with the organic hydrides in the DMSO solvent. Finally, we outline our approaches to the closure of the catalytic cycle via the electrochemical and photochemical regeneration of the hydride (R–H) from the conjugate hydride acceptors (R + ). We illustrate how proton-coupled electron transfer can be efficiently utilized not only to lower the electrochemical potential at which the hydride regeneration takes place but also to suppress the unwanted dimerization that neutral radical intermediates tend to undergo. Overall, this account provides a summary of important milestones achieved in organocatalytic CO 2 reduction and provides insights into the future research directions needed for the discovery of inexpensive catalysts for carbon recycling.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Understanding the Role of Functional Groups in Polymeric Binder for Electrochemical Carbon Dioxide Reduction on Gold Nanoparticles

Electrochemical CO 2 reduction reaction (CO 2 RR) is one of the promising strategies for converting CO 2 to value-added chemicals. Gold (Au) catalysts are considered to be the best benchmarking materials for CO 2 RR to produce CO. In this work, the role of different functional groups of polymeric binders on CO 2 RR over Au catalysts is systematically investigated by combined experimental measurements and density functional theory (DFT) calculations. Especially, it is revealed that the functional groups can play a role in suppressing the undesired hydrogen evolution reaction, the main competing reaction against CO 2 RR, thus enabling more catalytic active sites to be available for CO 2 RR and enhancing the CO 2 RR activity. Consistent with the DFT prediction, fluorine (F)-containing functional groups in the F-rich polytetrafluoroethylene binder lead to a high Faradaic efficiency (≈94.7%) of CO production. Finally, this study suggests a new strategy by optimizing polymeric binders for the selective CO 2 RR.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Establishing a Theoretical Landscape for Identifying Basal Plane Active 2D Metal Borides (MBenes) toward Nitrogen Electroreduction

Abstract To achieve efficient ammonia synthesis via electrochemical nitrogen reduction reaction (NRR), a qualified catalyst should have both high specific activity and large active surface area. However, integrating these two merits into one single material remains a big challenge due to the difficulty in balancing multiple reaction intermediates. Here, it is demonstrated that the boron‐analogues of MXenes, namely “MBenes”, could cope with the challenge and achieve the high activity and large reaction region simultaneously toward NRR. Using extensive density functional theory computations and taking 16 MBenes as representatives, it is identified that seven MBenes (CrB, MoB, WB, Mo 2 B, V 3 B 4 , CrMnB 2 , and CrFeB 2 ) not only have intrinsic basal plane activity for NRR with limiting potentials ranging from −0.22 to −0.82 V, but also possess superior capability of suppressing the competitive hydrogen evolution reaction. Particularly, different from the MXenes whose surface oxidation may block the active sites, once oxidized, these MBenes can catalyze NRR via the self‐activating process, reducing O*/OH* into H 2 O* under reaction conditions, and favoring the N 2 electroreduction. As a result, the exceptional activity and selectivity, high active area (≈10 19 m −2 ), and antioxidation nature render these MBenes as pH‐universal catalysts for NH 3 production without introducing any dopants and defects.

Guo, Xiangyu↗
DOE OSTI2023

Fe-N 4 O-C Nanoplates Covalently Bonding on Graphene for Efficient CO 2 Electroreduction and Zn-CO 2 Batteries

Electrochemical carbon dioxide (CO 2 ) reduction into value-added products holds great promise in moving toward carbon neutrality but remains a grand challenge due to lack of efficient electrocatalysts. Herein, the nucleophilic substitution reaction is elaborately harnessed to synthesize carbon nanoplates with a Fe-N 4 O configuration anchored onto graphene substrate (Fe-N 4 O-C/Gr) through covalent linkages. Density functional theory calculations demonstrate the unique configuration of Fe-N 4 O with one oxygen (O) atom in the axial direction not only suppresses the competing hydrogen evolution reaction, but also facilitates the desorption of *CO intermediate compared with the commonly planar single-atomic Fe sites. The Fe-N 4 O-C/Gr shows excellent performance in the electroreduction of CO 2 into carbon monoxide (CO) with an impressive Faradaic efficiency of 98.3% at -0.7 V versus reversible hydrogen electrode (RHE) and a high turnover frequency of 3511 h -1 . Furthermore, as a cathode catalyst in an aqueous zinc (Zn)-CO 2 battery, the Fe-N 4 O-C/Gr achieves a high CO Faradaic efficiency (≈91%) at a discharge current density of 3 mA cm -2 and long-term stability over 74 h. Here this work opens up a new route to simultaneously modulate the geometric and electronic structure of single-atomic catalysts toward efficient CO 2 conversion.

25 ENERGY STORAGE↗