Browse
Submit Data
Databases
API
Help

Dataset Information

27 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Electrochemical Reduction of CO₂ to CO over Transition Metal/N-Doped Carbon Catalysts: The Active Sites and Reaction Mechanism.

ABSTRACT: Electrochemical CO₂ reduction to value-added chemicals/fuels provides a promising way to mitigate CO₂ emission and alleviate energy shortage. CO₂ -to-CO conversion involves only two-electron/proton transfer and thus is kinetically fast. Among the various developed CO₂ -to-CO reduction electrocatalysts, transition metal/N-doped carbon (M-N-C) catalysts are attractive due to their low cost and high activity. In this work, recent progress on the development of M-N-C catalysts for electrochemical CO₂ -to-CO conversion is reviewed in detail. The regulation of the active sites in M-N-C catalysts and their related adjustable electrocatalytic CO₂ reduction performance is discussed. A visual performance comparison of M-N-C catalysts for CO₂ reduction reaction (CO₂ RR) reported over the recent years is given, which suggests that Ni and Fe-N-C catalysts are the most promising candidates for large-scale reduction of CO₂ to produce CO. Finally, outlooks and challenges are proposed for future research of CO₂ -to-CO conversion.

SUBMITTER: Liang S

PROVIDER: S-EPMC8693035 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Metal-Doped PdH(111) Catalysts for CO2 Reduction.

Project description:PdH-based catalysts hold promise for both CO2 reduction to CO and the hydrogen evolution reaction. Density functional theory is used to systematically screen for stability, activity, and selectivity of transition metal dopants in PdH. The transition metal elements Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Ru, Rh, Ag, Cd, Hf, Ta, W, and Re are doped into PdH(111) surface with six different doping configurations: single, dimer, triangle, parallelogram, island, and overlayer. We find that several dopants, such as Ti and Nb, have excellent predicted catalytic activity and CO2 selectivity compared to the pure PdH hydride. In addition, they display good stability due to their negative doping formation energy. The improved performance can be assigned to reaction intermediates forming two bonds consisting of one C-Metal and one O-Metal bond on the PdH surface, which break the scaling relations of intermediates, and thus have stronger HOCO* binding facilitating CO2 activation.

| S-EPMC9320891 | biostudies-literature

Highly effective sites and selectivity of nitrogen-doped graphene/CNT catalysts for CO2 electrochemical reduction.

Project description:Metal-free catalysts, such as graphene/carbon nanostructures, are highly cost-effective to replace expensive noble metals for CO2 reduction if fundamental issues, such as active sites and selectivity, are clearly understood. Using both density functional theory (DFT) and ab initio molecular dynamic calculations, we show that the interplay of N-doping and curvature can effectively tune the activity and selectivity of graphene/carbon-nanotube (CNT) catalysts. The CO2 activation barrier can be optimized to 0.58 eV for graphitic-N doped graphene edges, compared with 1.3 eV in the un-doped counterpart. The graphene catalyst without curvature shows strong selectivity for CO/HCOOH production, whereas the (6, 0) CNT with a high degree of curvature is effective for both CH3OH and HCHO production. Curvature is also very influential to tune the overpotential for a given product, e.g. from 1.5 to 0.02 V for CO production and from 1.29 to 0.49 V for CH3OH production. Hence, the graphene/CNT nanostructures offer great scope and flexibility for effective tunning of catalyst efficiency and selectivity, as shown here for CO2 reduction.

| S-EPMC5975832 | biostudies-literature

Understanding activity and selectivity of metal-nitrogen-doped carbon catalysts for electrochemical reduction of CO2.

Project description:Direct electrochemical reduction of CO2 to fuels and chemicals using renewable electricity has attracted significant attention partly due to the fundamental challenges related to reactivity and selectivity, and partly due to its importance for industrial CO2-consuming gas diffusion cathodes. Here, we present advances in the understanding of trends in the CO2 to CO electrocatalysis of metal- and nitrogen-doped porous carbons containing catalytically active M-N x moieties (M = Mn, Fe, Co, Ni, Cu). We investigate their intrinsic catalytic reactivity, CO turnover frequencies, CO faradaic efficiencies and demonstrate that Fe-N-C and especially Ni-N-C catalysts rival Au- and Ag-based catalysts. We model the catalytically active M-N x moieties using density functional theory and correlate the theoretical binding energies with the experiments to give reactivity-selectivity descriptors. This gives an atomic-scale mechanistic understanding of potential-dependent CO and hydrocarbon selectivity from the M-N x moieties and it provides predictive guidelines for the rational design of selective carbon-based CO2 reduction catalysts.Inexpensive and selective electrocatalysts for CO2 reduction hold promise for sustainable fuel production. Here, the authors report N-coordinated, non-noble metal-doped porous carbons as efficient and selective electrocatalysts for CO2 to CO conversion.

| S-EPMC5643516 | biostudies-literature

High-ammonia selective metal-organic framework-derived Co-doped Fe/Fe2O3 catalysts for electrochemical nitrate reduction.

Project description:Ammonia (NH3) is an ideal carbon-free power source in the future sustainable hydrogen economy for growing energy demand. The electrochemical nitrate reduction reaction (NO3 -RR) is a promising approach for nitrate removal and NH3 production at ambient conditions, but efficient electrocatalysts are lacking. Here, we present a metal-organic framework (MOF)-derived cobalt-doped Fe@Fe2O3 (Co-Fe@Fe2O3) NO3 -RR catalyst for electrochemical energy production. This catalyst has a nitrate removal capacity of 100.8 mg N gcat -1 h-1 and an ammonium selectivity of 99.0 ± 0.1%, which was the highest among all reported research. In addition, NH3 was produced at a rate of 1,505.9 μg h-1 cm-2, and the maximum faradaic efficiency was 85.2 ± 0.6%. Experimental and computational results reveal that the high performance of Co-Fe@Fe2O3 results from cobalt doping, which tunes the Fe d-band center, enabling the adsorption energies for intermediates to be modulated and suppressing hydrogen production. Thus, this study provides a strategy in the design of electrocatalysts in electrochemical nitrate reduction.

| S-EPMC8833204 | biostudies-literature

Metal-organic framework derived single-atom catalysts for electrochemical CO2 reduction.

Project description:With maximum atomic utilization, transition metal single atom catalysts (SACs) show great potential in electrochemical reduction of CO2 to CO. Herein, by a facile pyrolysis of zeolitic imidazolate frameworks (ZIFs) assembled with tiny amounts of metal ions, a series of metal-nitrogen-carbon (M-N-C) based SACs (M = Fe, Ni, Mn, Co and Cu), with metal single atoms decorated on a nitrogen-doped carbon support, have been precisely constructed. X-ray photoelectron spectroscopy (XPS) for M-N-C showed that the N 1s spectrum was deconvoluted into five peaks for pyridinic (∼398.3 eV), M-N coordination (∼399.6 eV), pyrrolic (∼400.4 eV), quaternary (∼401.2 eV) and oxidized (∼402.9 eV) N species, demonstrating the existence of M-N bonding. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) indicates homogeneous distribution of metal species throughout the N-doped carbon matrix. Among the catalysts examined, the Fe-N-C catalyst exhibits the best catalytic performance in electrocatalytic CO2 reduction reaction (CO2RR) with nearly 100% faradaic efficiency for CO (FECO) at -0.9 V vs. the reversible hydrogen electrode (RHE). Ni-N-C is the second most active catalyst towards CO2RR performance, then followed by Mn-N-C, Co-N-C and Cu-N-C. Considering the optimum activity of Fe-N-C catalyst for the CO2RR, we then further investigate the effect of pyrolysis temperature on CO2RR of the Fe-N-C catalyst. We find the Fe-N-C catalyst pyrolyzed at 1000 °C exhibits the best catalytic activity in CO2RR with excellent CO selectivity.

| S-EPMC9661489 | biostudies-literature

Toward Highly Selective Electrochemical CO2 Reduction using Metal-Free Heteroatom-Doped Carbon.

Project description:There are growing interests in metal-free heteroatom-doped carbons for electrochemical CO2 reduction. Previous studies extensively focus on the effect of N-doping, and their products severely suffer from low current density (mostly <2 mA cm-2) and limited selectivity (<90%). Here, it is reported that heteroatom codoping offers a promising solution to the above challenge. As a proof of concept, N,P-codoped mesoporous carbon is prepared by annealing phytic-acid-functionalized ZIF-8 in NH3. In CO2-saturated 0.5 m NaHCO3, the catalyst enables CO2 reduction to CO with great selectivity close to 100% and large CO partial current density (≈8 mA cm-2), which are, to the best of knowledge, superior to all other relevant competitors. Theoretical simulations show that the improved activity and selectivity are stemmed from the enhanced surface adsorption of *COOH and *CO intermediates as a result of the synergy of N and P codoping.

| S-EPMC7435239 | biostudies-literature

Rational design of graphdiyne-based single-atom catalysts for electrochemical CO2 reduction reaction.

Project description:Graphdiyne (GDY) has achieved great success in the application of two-dimensional carbon materials in recent years due to its excellent electrochemical catalytic capacity. Considering the unique electronic structure of GDY, transition metal (TM1) (TM = Fe, Ru, Os, Co, Rh, Ir) single-atom catalysts (SACs) with isolated loading on GDY were designed for electrochemical CO2 reduction reaction (CO2RR) with density functional theoretical (DFT) calculations. The charge density difference and projected densities of states have been systematically calculated. The mechanism of electrochemical catalysis and the reaction pathway of CO2RR over Os1/GDY catalysts have also been investigated and high catalytic activity was found for the generation of methane. The calculated results provide a theoretical basis for the design of efficient GDY-based SACs for electrochemical CO2RR.

| S-EPMC11350510 | biostudies-literature

Control over Electrochemical CO2 Reduction Selectivity by Coordination Engineering of Tin Single-Atom Catalysts.

Project description:Carbon-based single-atom catalysts (SACs) with well-defined and homogeneously dispersed metal-N4 moieties provide a great opportunity for CO2 reduction. However, controlling the binding strength of various reactive intermediates on catalyst surface is necessary to enhance the selectivity to a desired product, and it is still a challenge. In this work, the authors prepared Sn SACs consisting of atomically dispersed SnN3 O1 active sites supported on N-rich carbon matrix (Sn-NOC) for efficient electrochemical CO2 reduction. Contrary to the classic Sn-N4 configuration which gives HCOOH and H2 as the predominant products, Sn-NOC with asymmetric atomic interface of SnN3 O1 gives CO as the exclusive product. Experimental results and density functional theory calculations show that the atomic arrangement of SnN3 O1 reduces the activation energy for *COO and *COOH formation, while increasing energy barrier for HCOO* formation significantly, thereby facilitating CO2 -to-CO conversion and suppressing HCOOH production. This work provides a new way for enhancing the selectivity to a specific product by controlling individually the binding strength of each reactive intermediate on catalyst surface.

| S-EPMC8655193 | biostudies-literature

Pd-incorporated polyoxometalate catalysts for electrochemical CO2 reduction.

Project description:Polyoxometalates (POMs), representing anionic metal-oxo clusters, display diverse properties depending on their structures, constituent elements, and countercations. These characteristics position them as promising catalysts or catalyst precursors for electrochemical carbon dioxide reduction reaction (CO2RR). This study synthesized various salts-TBA+ (tetra-n-butylammonium), Cs+, Sr2+, and Ba2+-of a dipalladium-incorporated POM (Pd2, [γ-H2SiW10O36Pd2(OAc)2]4-) immobilized on a carbon support (Pd2/C). The synthesized catalysts-TBAPd2/C, CsPd2/C, SrPd2/C, and BaPd2/C-were deposited on a gas-diffusion carbon electrode, and the CO2RR performance was subsequently evaluated using a gas-diffusion flow electrolysis cell. Among the catalysts tested, BaPd2/C exhibited high selectivity toward carbon monoxide (CO) production (ca. 90%), while TBAPd2/C produced CO and hydrogen (H2) with moderate selectivity (ca. 40% for CO and ca. 60% for H2). Moreover, BaPd2/C exhibited high selectivity toward CO production over 12 h, while palladium acetate, a precursor of Pd2, showed a significant decline in CO selectivity during the CO2RR. Although both BaPd2/C and TBAPd2/C transformed into Pd nanoparticles and WO x nanospecies during the CO2RR, the influence of countercations on their product selectivity was significant. These results highlight that POMs and their countercations can effectively modulate the catalytic performance of POM-based electrocatalysts in CO2RR.

| S-EPMC11342151 | biostudies-literature

Structure-activity relationship of Cu-based catalysts for the highly efficient CO2 electrochemical reduction reaction.

Project description:Electrocatalytic carbon dioxide reduction (CO2RR) is a relatively feasible method to reduce the atmospheric concentration of CO2. Although a series of metal-based catalysts have gained interest for CO2RR, understanding the structure-activity relationship for Cu-based catalysts remains a great challenge. Herein, three Cu-based catalysts with different sizes and compositions (Cu@CNTs, Cu4@CNTs, and CuNi3@CNTs) were designed to explore this relationship by density functional theory (DFT). The calculation results show a higher degree of CO2 molecule activation on CuNi3@CNTs compared to that on Cu@CNTs and Cu4@CNTs. The methane (CH4) molecule is produced on both Cu@CNTs and CuNi3@CNTs, while carbon monoxide (CO) is synthesized on Cu4@CNTs. The Cu@CNTs showed higher activity for CH4 production with a low overpotential value of 0.36 V compared to CuNi3@CNTs (0.60 V), with *CHO formation considered the potential-determining step (PDS). The overpotential value was only 0.02 V for *CO formation on the Cu4@CNTs, and *COOH formation was the PDS. The limiting potential difference analysis with the hydrogen evolution reaction (HER) indicated that the Cu@CNTs exhibited the highest selectivity of CH4 among the three catalysts. Therefore, the sizes and compositions of Cu-based catalysts greatly influence CO2RR activity and selectivity. This study provides an innovative insight into the theoretical explanation of the origin of the size and composition effects to inform the design of highly efficient electrocatalysts.

| S-EPMC9947715 | biostudies-literature