Efficient Carbon Dioxide Reduction Research Articles

Manipulating Iron(II) Carbonyl Intermediate for Efficient Carbon Dioxide Reduction

Manipulating Iron(II) Carbonyl Intermediate for Efficient Carbon Dioxide Reduction

Novel spherical InVO4/floral Bi2MoO6 Z-scheme heterojunction for efficient photocatalytic carbon dioxide reduction

The development of efficient CO2 reduction photocatalysts is of great significance to improving the global greenhouse effect and alleviating the energy crisis. In this paper, spherical InVO4/floral Bi2MoO6 (IVO/BMO) Z-scheme heterojunction was prepared by a hydrothermal method, and the surface structure, chemical composition, and photovoltaic properties of the samples were characterized and tested for their CO2 reduction performance. The experimental results show that 1.5 %-IVO/BMO exhibits excellent photocatalytic activity for CO2 reduction under the irradiation of 300 W Xenon lamp, with a CO yield of 34.08 µmol/g/h and a CH4 yield of 4.49 µmol/g/h, which are 2.55 and 1.05 times higher than that of the pure Bi2MoO6, respectively. The enhanced photocatalytic activity can be attributed to the formation of an IVO/BMO Z-scheme heterojunction, which promotes electron separation and reduces charge recombination at the interface, facilitating the reaction process. This study provides a novel Z-scheme photocatalyst for efficient carbon dioxide reduction.

Thermal-driven Dispersion of Bismuth Nanoparticles among Carbon Matrix for Efficient Carbon Dioxide Reduction.

The poor electrocatalytic stability and rapid deactivation of metal electrocatalysts are always present in the electrocatalytic conversion of carbon dioxide (CO2) due to the harsh reduction condition. Herein, we demonstrate the controllable dispersion of ultrafine bismuth nanoparticles among the hollow carbon shell (Bi@C-700-4) simply by a thermal-driven diffusion process. The confinement effect of nitrogen-doped carbon matrix is able to low the surface energy of bismuth nanoparticles against the easy aggregation commonly observed for the thermal treatment. On the basis of the synergistic effect and confinement effect between bismuth nanoparticles and carbon matrix, the highly dispersed active sites render the obviously improved electrocatalytic activity and stability for carbon dioxide reduction into formate. The in-situ experimental observation on the reduction process and theoretical calculations reveal that the incorporation of bismuth nanoparticles with nitrogen-doped carbon matrix would promote the activation of CO2 and the easy formation of key intermediate (*OCHO), thus leading the enhanced electrocatalytic activity, with a Faradaic Efficiency (FE) of formate about 94.8% and the long-time stability. Furthermore, the coupling of an anode for 5-hydroxymethylfurfural oxidation reaction (HMFOR) in solar-driven system renders the high 2,5-furandicarboxylic acid (FDCA) yield of 81.2%, presenting the impressive solar-to-fuel conversion.

Rapid Joule-heating synthesis of metal/carbon-based electrocatalysts for efficient carbon dioxide reduction

Carbon-loaded metal nanoparticles (NPs) are widely employed as functional materials for electrocatalysis. In this study, a rapid thermal shock method was developed to load various metal nanoparticles onto carbon supports. Compared to conventional pyrolysis processes, Joule heating enables rapid heating to elevated temperatures within a short period, effectively preventing the migration and aggregation of metal atoms. Simultaneously, the anchoring effect of defective carbon carriers ensures the uniform distribution of NPs on the carbon supports. Additionally, nitrogen doping can significantly enhance the electronic conductivity of the carbon matrix and strengthen the metal-carbon interactions, thereby synergistically improving catalyst performance. When used as electrocatalysts for electrocatalytic CO2 reduction, bismuth-, indium-, and tin/carbon-carrier-based catalysts exhibit excellent Faraday efficiencies of 92.8%, 86.4%, and 73.3%, respectively, for formate generation in flow cells. The influence of different metals and calcination temperatures on catalytic performance was examined to provide valuable insights into the rational design of carbon-based electrocatalysts with enhanced electrocatalytic activity.

In situ embedded bismuth nanoparticles among highly porous carbon fibers for efficient carbon dioxide reduction

In situ embedded bismuth nanoparticles among highly porous carbon fibers for efficient carbon dioxide reduction

Mechanistic and Electronic Insights into Efficient Carbon Dioxide Reduction Driven by Visible Light Using a Coordination Polymer

Mechanistic and Electronic Insights into Efficient Carbon Dioxide Reduction Driven by Visible Light Using a Coordination Polymer

Low‐coordination Nanocrystalline Copper‐based Catalysts through Theory‐guided Electrochemical Restructuring for Selective CO2 Reduction to Ethylene

AbstractRevealing the dynamic reconstruction process and tailoring advanced copper (Cu) catalysts is of paramount significance for promoting the conversion of CO2 into ethylene (C2H4), paving the way for carbon neutralization and facilitating renewable energy storage. In this study, we initially employed density functional theory (DFT) and molecular dynamics (MD) simulations to elucidate the restructuring behavior of a catalyst under electrochemical conditions and delineated its restructuring patterns. Leveraging insights into this restructuring behavior, we devised an efficient, low‐coordination copper‐based catalyst. The resulting synthesized catalyst demonstrated an impressive Faradaic efficiency (FE) exceeding 70 % for ethylene generation at a current density of 800 mA cm−2. Furthermore, it showed robust stability, maintaining consistent performance for 230 hours at a cell voltage of 3.5 V in a full‐cell system. Our research not only deepens the understanding of the active sites involved in designing efficient carbon dioxide reduction reaction (CO2RR) catalysts but also advances CO2 electrolysis technologies for industrial application.

Low-coordination Nanocrystalline Copper-based Catalysts through Theory-guided Electrochemical Restructuring for Selective CO2 Reduction to Ethylene.

Revealing the dynamic reconstruction process and tailoring advanced copper (Cu) catalysts is of paramount significance for promoting the conversion of CO2 into ethylene (C2H4), paving the way for carbon neutralization and facilitating renewable energy storage. In this study, we initially employed density functional theory (DFT) and molecular dynamics (MD) simulations to elucidate the restructuring behavior of a catalyst under electrochemical conditions and delineated its restructuring patterns. Leveraging insights into this restructuring behavior, we devised an efficient, low-coordination copper-based catalyst. The resulting synthesized catalyst demonstrated an impressive Faradaic efficiency (FE) exceeding 70 % for ethylene generation at a current density of 800 mA cm-2. Furthermore, it showed robust stability, maintaining consistent performance for 230 hours at a cell voltage of 3.5 V in a full-cell system. Our research not only deepens the understanding of the active sites involved in designing efficient carbon dioxide reduction reaction (CO2RR) catalysts but also advances CO2 electrolysis technologies for industrial application.

Easily constructed porous silver films for efficient catalytic CO2 reduction and Zn-CO2 batteries.

For the electroreduction of carbon dioxide into high value-added chemicals, highly active and selective catalysts are crucial, and metallic silver is one of the most intriguing candidate materials available at a reasonable cost. Herein, through a novel two-step operation of Ag paste/SBA-15 coating and HF etching, porous silver films on a commercial carbon paper with a waterproofer (p-Ag/CP) could be easily fabricated on a large scale as highly efficient carbon dioxide reduction reaction (CO2RR) electrocatalysts with a CO Faraday efficiency (FECO) as high as 96.7% at -1.0 V vs. the reversible hydrogen electrode (RHE), and it still reaches up to 90% FECO over applied potentials ranging from -0.8 to -1.1 V vs. the RHE. Meanwhile, the membrane electrode assembly (MEA) utilizing the p-Ag/CP catalyst has achieved a current density, FECO, and stability of ∼60 mA cm-2, >91%, and 11 h, respectively. Furthermore, the assembled aqueous Zn-CO2 battery using p-Ag/CP cathode yielded a peak power density of 0.34 mW cm-2, 75 charge-discharge cycles for 25 h, and 64% FECO at 2.5 mA cm-2. Compared with flat Ag/CP, the significant enhancement in the CO2RR activity of p-Ag/CP was mainly attributed to the distinctive porous structure and an improved three-phase boundary, which is capable of inducing the stabilization of *COOH intermediates, increased active specific surface areas, fast electron transfer kinetic and mass transportation. Further, theoretical calculations revealed that p-Ag/CP possessed an optimized energy barrier for *COOH intermediates.

Recent Progress on Perovskite-Based Electrocatalysts for Efficient CO2 Reduction.

An efficient carbon dioxide reduction reaction (CO2RR), which reduces CO2 to low-carbon fuels and high-value chemicals, is a promising approach for realizing the goal of carbon neutrality, for which effective but low-cost catalysts are critically important. Recently, many inorganic perovskite-based materials with tunable chemical compositions have been applied in the electrochemical CO2RR, which exhibited advanced catalytic performance. Therefore, a timely review of this progress, which has not been reported to date, is imperative. Herein, the physicochemical characteristics, fabrication methods and applications of inorganic perovskites and their derivatives in electrochemical CO2RR are systematically reviewed, with emphasis on the structural evolution and product selectivity of these electrocatalysts. What is more, the current challenges and future directions of perovskite-based materials regarding efficient CO2RR are proposed, to shed light on the further development of this prospective research area.

A DFT screening of transition metal single-atom catalyst anchored on Janus WSSe basal plane for highly efficient carbon dioxide reduction reaction

Electrochemical CO2 reduction reaction (CO2RR) can efficiently and selectively reduce carbon dioxide into chemical fuel. Here, we designed the novel catalysts of transition-metal atoms anchored on Janus WSSe basal plane (TM@SSe) monolayer by first-principles calculations. The results show that Zn@WSSe has the best CO2RR catalytic activity with limit potential of -0.32 V and a high selectivity for the competitive hydrogen precipitation reaction (HER). Moreover, ab initio molecular dynamics simulation (AIMD) calculation at 300 K indicated high thermodynamic stability of Zn@WSSe. The study of the rate limiting step (CO*+H++e−→ *CHO) of the Zn@WSSe structure illustrates that the CO2RR catalytic activity of these candidate catalysts largely depends on the better interaction between Zn atoms and surrounding W atoms, which H atom is more easily adsorbed to C atom, making the reaction process easier to achieve. The above research provides a new way to design efficient CO2RR electrocatalyst under ambient conditions.

Photoinduced Metastable Asymmetric Cu Single Atoms for Photoreduction of CO2 to Ethylene

AbstractMetastable structures are promising candidates for efficient catalysis owing to abundant active electronic states, strong electronic coupling with reactants, and energetic preference. Exerting the value of metastable structures while evading the difficulty in direct synthesis remains challenging. Herein, it is reported that light irradiation enables the generation and maintenance of the metastable state over copper single atoms for efficient carbon dioxide reduction. Under irradiation with light, photogenerated electrons transit to Cu‐3d orbits and initiate d‐orbital rearrangement. The initial symmetric Cu1─O4 coordination converts to the metastable asymmetric structure of Cu1─O2+1, and is reversibly restored after removing the light. The photoinduced metastable intermediate of Cu1─O2+1 promotes the Cu single‐atom catalyst to deliver an ethylene yield rate of 60.4 µmol gcat.−1 h−1. Mechanistic studies reveal that Cu1─O2+1 possesses stronger adsorption capability for reactants and intermediates. The reaction energy barrier over Cu1─O2+1 also shows an obvious decline compared to that over Cu1─O4.

Chlorine-Coordinated Unsaturated Ni-N2 Sites for Efficient Electrochemical Carbon Dioxide Reduction.

Heteroatom-doping is an effective method for modifying the geometric symmetry of metal-nitrogen-carbon (M-N-C) single-atom catalysts and thereby tuning the electronic structure. Up to now, most of the current reports have concentrated on introducing heteroatoms into the highly symmetrical M-N4 structure. The coordination-unsaturated M-N2 structure is more sterically favorable for the insertion of alien atoms to optimize the electronic structure. Herein, a Ni-N2 catalyst with out-of-plane coordinated chlorine(Cl) atoms (Ni-N2 Cl/C) is successfully constructed on chlorine-functionalized carbon supports (C-Cl) for an efficient carbon dioxide reduction reaction (CO2 RR). Density functional theory calculations demonstrate that the prepared Ni-N2 Cl/C catalyst exhibits a higher capability in balancing COOH* formation and CO* desorption. In addition, in situ Raman spectra confirm that the lower CO binding energy on the Ni-N2 Cl/C facilitates CO escape, leading to excellent CO2 RR performance. A high CO Faradaic efficiency (FECO ) of more than 80% is achieved from -0.6 to -1.2V versus reversible hydrogen electrode on the Ni-N2 Cl/C and it exhibits negligible FECO and current declination over a 40-h stability test. Furthermore, a high turnover frequency (TOF) value of 15 808 h-1 is obtained, which is more than ten times that of Ni-N2 /C (1476 h-1 ) without coordinated Cl atoms.

Two-Dimensional Metal Coordination Polymer Derived Indium Nanosheet for Efficient Carbon Dioxide Reduction to Formate.

Main group indium materials have been known as promising electrocatalysts for two-electron-involved carbon dioxide reduction to produce formate, which is a key energy vector in many industrial reactions. However, the synthesis of two-dimensional (2D) monometallic nonlayered indium remains a great challenge. Here, we present a facile electrochemical reduction strategy to transform 2D indium coordination polymer into elemental indium nanosheets. In a customized flow cell, the reconstructed metallic indium exhibits a high Faradaic efficiency (FE) of 96.3% for formate with a maximum partial current density exceeding 360 mA cm-2 and negligible degradation after 140 h operation in 1 M KOH solution, outperforming the state-of-the-art indium-based electrocatalysts. Moreover, in and ex situ electrochemical analysis and characterizations demonstrate that the enhanced exposure of active sites and mass/charge transport at the CO2 gas-catalyst-electrolyte triple-phase interface and the restrained electrolyte flooding are contributing to producing and stabilizing carbon dioxide radical anion intermediates, thus leading to superior catalytic performance.

Metalloporphyrin-Based Metal–Organic Frameworks for Photocatalytic Carbon Dioxide Reduction: The Influence of Metal Centers

Photocatalysis is one of the most promising technologies to achieve efficient carbon dioxide reduction reaction (CO2RR) under mild conditions. Herein, metalloporphyrin-based metal–organic frameworks (MOFs) with different metal centers, denoted as PCN-222, were utilized as visible-light photocatalysts for CO2 reduction. Due to the combination of the conjugated planar macrocyclic structures of metalloporphyrins and the stable porous structures of MOFs, all PCN-222 materials exhibited excellent light-harvesting and CO2-adsorbing abilities. Among the studied MOFs of varied metal centers (M = Pt, Fe, Cu, Zn, Mn), PCN-222(2H&Zn) exhibited the highest photocatalytic CO2RR performance, with an average CO yield of 3.92 μmol g−1 h−1 without any organic solvent or sacrificial agent. Furthermore, this was three and seven times higher than that of PCN-222(Zn) (1.36 μmol g−1 h−1) and PCN-222(2H) (0.557 μmol g−1 h−1). The superior photocatalytic activity of PCN-222(2H&Zn) was attributed to its effective photoexcited electron–hole separation and transportation compared with other PCN-222(2H&M) materials. The obtained results indicate that Zn ions in the porphyrin’s center played an important role in the reaction of active sites for the adsorption–activation of CO2. In addition, PCN-222(2H&Zn) showed the highest CO2 selectivity (almost 100%) and stability. This work provides a clear guide for the design of efficient photocatalysts.

Carbon-Confined Indium Oxides for Efficient Carbon Dioxide Reduction in a Solid-State Electrolyte Flow Cell.

Developing robust electrocatalysts and advanced devices is important for electrochemical carbon dioxide (CO2 ) reduction toward the generation of valuable chemicals. We present herein a carbon-confined indium oxide electrocatalyst for stable and efficient CO2 reduction. The reductive corrosion of oxidative indium to the metallic state during electrolysis could be prevented by carbon protection, and the applied carbon layer also optimizes the reaction intermediate adsorption, which enables both high selectivity and activity for CO2 reduction. In a liquid-phase flow cell, the formate selectivity exceeds 90 % in a wide potential window from -0.8 V to -1.3 V vs. RHE. The continuous production of ca. 0.12 M pure formic acid solution is further demonstrated at a current density of 30 mA cm-2 in a solid-state electrolyte mediated reactor. This work provides significant concepts in the parallel development of electrocatalysts and devices for carbon-neutral technologies.

Carbon‐Confined Indium Oxides for Efficient Carbon Dioxide Reduction in a Solid‐State Electrolyte Flow Cell

AbstractDeveloping robust electrocatalysts and advanced devices is important for electrochemical carbon dioxide (CO2) reduction toward the generation of valuable chemicals. We present herein a carbon‐confined indium oxide electrocatalyst for stable and efficient CO2 reduction. The reductive corrosion of oxidative indium to the metallic state during electrolysis could be prevented by carbon protection, and the applied carbon layer also optimizes the reaction intermediate adsorption, which enables both high selectivity and activity for CO2 reduction. In a liquid‐phase flow cell, the formate selectivity exceeds 90 % in a wide potential window from −0.8 V to −1.3 V vs. RHE. The continuous production of ca. 0.12 M pure formic acid solution is further demonstrated at a current density of 30 mA cm−2 in a solid‐state electrolyte mediated reactor. This work provides significant concepts in the parallel development of electrocatalysts and devices for carbon‐neutral technologies.

Porphyrin Coordination Polymer with Dual Photocatalytic Sites for Efficient Carbon Dioxide Reduction.

The resurgence of visible light photocatalysis for carbon dioxide reduction reaction (CO2RR) has resulted in the generation of various homogeneous and heterogeneous paradigms. Herein, a new system has been established by incorporating dual catalytic sites into porous coordination polymer toward the photocatalysis of CO2RR. A functional ligand, 5,10,15,20-tetrakis[4'-(terpyridinyl)phenyl]porphyrin (TTPP), has been used to assemble discrete divalent nickel ions into the coordination polymer (TTPP-Ni) through metal bis(terpyridine) nodes. Both the porphyrin and terpyridine moieties prefer to bind with nickel ions, giving rise to TTPP-Ni with dual active catalytic sites. By controlling different molar ratios of ligand and metal and the reaction temperature, four samples including TTPP-Ni-n (n = 1, 2, 3, and 4) with different molar ratios of nickel porphyrin and nickel bis(terpyridine) subunits have been fabricated. The predesigned two-dimensional chemical structures of TTPP-Ni samples have been fully characterized using powder X-ray diffraction, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and IR and UV-vis spectroscopies. The photocatalytic activities of these coordination polymers have been screened using [Ru(bpy)3]Cl2·6H2O as a photosensitizer together with triisopropanolamine as the sacrificial electron donor in CH3CN and H2O. Among these photocatalysts, TTPP-Ni-3 and TTPP-Ni-4 with almost saturated metal sites are able to display extraordinary photocatalytic performance including a CO generation rate of ca. 3900 μmol g-1 h-1 and 98% selectivity. The mechanism associated with dual active sites has been rationalized on the basis of theoretical simulations.

Graphdiyne-supported single-cluster electrocatalysts for highly efficient carbon dioxide reduction reaction.

The electrochemical CO2 reduction reaction (CO2RR) has become a promising technology to resolve globally accelerating CO2 emissions and produce chemical fuels. In this work, the electrocatalytic performance of transition metal (TM = Cu, Cr, Mn, Co, Ni, Mo, Pt, Rh, Ru and V) triatomic clusters embedded in a graphdiyne (GDY) monolayer (TM3@GDY) for CO2RR is investigated by density functional theory (DFT) calculations. The results indicate that Cr3@GDY possesses the best catalytic performance with a remarkably low rate-limiting step of 0.39 eV toward the CO2 product, and it can also effectively suppress the hydrogen evolution reaction (HER) during the entire CO2RR process. Studies on the rate-limiting steps (CHO* + H+ + e- → CHOH) of Crn@GDY (n = 1-4) structures demonstrate that the high catalytic performance is attributed to the strong synergistic reaction of three Cr atoms interacting with the C atom for the Cr3@GDY structure. The strong synergistic reaction gives rise to the weakest interaction between O-Cr atoms, which leads to the strongest interaction between O-H atoms and makes the hydrogenation process easier for the Cr3@GDY structure. Furthermore, ab initio molecular dynamics simulations (AIMD) at 500 K reveal the high thermodynamic stability of the Cr3@GDY structure. These studies may provide a new approach for designing highly efficient electrocatalysts for the CO2RR under ambient conditions.

MOF Encapsulating N-Heterocyclic Carbene-Ligated Copper Single-Atom Site Catalyst towards Efficient Methane Electrosynthesis.

The exploitation of highly efficient carbon dioxide reduction (CO2 RR) electrocatalyst for methane (CH4 ) electrosynthesis has attracted great attention for the intermittent renewable electricity storage but remains challenging. Here, N-heterocyclic carbene (NHC)-ligated copper single atom site (Cu SAS) embedded in metal-organic framework is reported (2Bn-Cu@UiO-67), which can achieve an outstanding Faradaic efficiency (FE) of 81 % for the CO2 reduction to CH4 at -1.5 V vs. RHE with a current density of 420 mA cm-2 . The CH4 FE of our catalyst remains above 70 % within a wide potential range and achieves an unprecedented turnover frequency (TOF) of 16.3 s-1 . The σ donation of NHC enriches the surface electron density of Cu SAS and promotes the preferential adsorption of CHO* intermediates. The porosity of the catalyst facilitates the diffusion of CO2 to 2Bn-Cu, significantly increasing the availability of each catalytic center.