共查询到20条相似文献,搜索用时 46 毫秒
1.
Lin Jia Hui Yang Jun Deng Junmei Chen Yuan Zhou Pan Ding Leigang Li Na Han Yanguang Li 《中国化学》2019,37(5):497-500
Electrocatalytic carbon dioxide reduction holds great promise for reducing the atmospheric CO2 level and alleviating the energy crisis. High‐performance electrocatalysts are often required in order to lower the high overpotential and expedite the sluggish reaction kinetics of CO2 electroreduction. Copper is a promising candidate metal. However, it usually suffers from the issues of poor stability and low product selectivity. In this work, bimetallic Cu‐Bi is obtained by reducing the microspherical copper bismuthate (CuBi2O4) for selectively catalyzing the CO2 reduction to formate (HCOO–). The bimetallic Cu‐Bi electrocatalyst exhibits high activity and selectivity with the Faradic efficiency over 90% in a wide potential window. A maximum Faradaic efficiency of ~95% is obtained at –0.93 V versus reversible hydrogen electrode. Furthermore, the catalyst shows high stability over 6 h with Faradaic efficiency of ~95%. This study provides an important clue in designing new functional materials for CO2 electroreduction with high activity and selectivity. 相似文献
2.
Dilan Karapinar Ngoc Tran Huan Nastaran Ranjbar Sahraie Jingkun Li David Wakerley Nadia Touati Sandrine Zanna Dario Taverna Luiz Henrique Galvo Tizei Andrea Zitolo Frdric Jaouen Victor Mougel Marc Fontecave 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(42):15242-15247
It is generally believed that CO2 electroreduction to multi‐carbon products such as ethanol or ethylene may be catalyzed with significant yield only on metallic copper surfaces, implying large ensembles of copper atoms. Here, we report on an inexpensive Cu‐N‐C material prepared via a simple pyrolytic route that exclusively feature single copper atoms with a CuN4 coordination environment, atomically dispersed in a nitrogen‐doped conductive carbon matrix. This material achieves aqueous CO2 electroreduction to ethanol at a Faradaic yield of 55 % under optimized conditions (electrolyte: 0.1 m CsHCO3, potential: ?1.2 V vs. RHE and gas‐phase recycling set up), as well as CO electroreduction to C2‐products (ethanol and ethylene) with a Faradaic yield of 80 %. During electrolysis the isolated sites transiently convert into metallic copper nanoparticles, as shown by operando XAS analysis, which are likely to be the catalytically active species. Remarkably, this process is reversible and the initial material is recovered intact after electrolysis. 相似文献
3.
Perfluorinated Covalent Triazine Framework Derived Hybrids for the Highly Selective Electroconversion of Carbon Dioxide into Methane 下载免费PDF全文
Yuanshuang Wang Junxiang Chen Genxiang Wang Yan Li Prof. Dr. Zhenhai Wen 《Angewandte Chemie (International ed. in English)》2018,57(40):13120-13124
Developing cost‐effective electrocatalysts for high‐selectivity CO2 electroreduction remains challenging. We herein report a perfluorinated covalent triazine framework (CTF) electrocatalyst that displays very high selectivity in the electroreduction of CO2 to CH4 with a faradaic efficiency of 99.3 % in aqueous electrolyte. Systematic characterization and electrochemical studies, in combination with density functional theory calculations, demonstrate that the presence of both nitrogen and fluorine in the CTF provides a unique pathway that is inaccessible with the individual components for CO2 electroreduction. 相似文献
4.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(38):11552-11556
Efficient, stable catalysts with high selectivity for a single product are essential if electroreduction of CO2 is to become a viable route to the synthesis of industrial feedstocks and fuels. A plasma oxidation pre‐treatment of silver foil enhances the number of low‐coordinated catalytically active sites, which dramatically lowers the overpotential and increases the activity of CO2 electroreduction to CO. At −0.6 V versus RHE more than 90 % Faradaic efficiency towards CO was achieved on a pre‐oxidized silver foil. While transmission electron microscopy (TEM) and operando X‐ray absorption spectroscopy showed that oxygen species can survive in the bulk of the catalyst during the reaction, quasi in situ X‐ray photoelectron spectroscopy showed that the surface is metallic under reaction conditions. DFT calculations reveal that the defect‐rich surface of the plasma‐oxidized silver foils in the presence of local electric fields drastically decrease the overpotential of CO2 electroreduction. 相似文献
5.
Fei‐Yue Gao Shao‐Jin Hu Xiao‐Long Zhang Ya‐Rong Zheng Hui‐Juan Wang Zhuang‐Zhuang Niu Peng‐Peng Yang Rui‐Cheng Bao Tao Ma Zheng Dang Yong Guan Xu‐Sheng Zheng Xiao Zheng Jun‐Fa Zhu Min‐Rui Gao Shu‐Hong Yu 《Angewandte Chemie (International ed. in English)》2020,59(22):8706-8712
A considerable challenge in the conversion of carbon dioxide into useful fuels comes from the activation of CO2 to CO2.? or other intermediates, which often requires precious‐metal catalysts, high overpotentials, and/or electrolyte additives (e.g., ionic liquids). We report a microwave heating strategy for synthesizing a transition‐metal chalcogenide nanostructure that efficiently catalyzes CO2 electroreduction to carbon monoxide (CO). We found that the cadmium sulfide (CdS) nanoneedle arrays exhibit an unprecedented current density of 212 mA cm?2 with 95.5±4.0 % CO Faraday efficiency at ?1.2 V versus a reversible hydrogen electrode (RHE; without iR correction). Experimental and computational studies show that the high‐curvature CdS nanostructured catalyst has a pronounced proximity effect which gives rise to large electric field enhancement, which can concentrate alkali‐metal cations resulting in the enhanced CO2 electroreduction efficiency. 相似文献
6.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(49):15813-15817
Electrochemical reduction of CO2 to ethanol, a clean and renewable liquid fuel with high heating value, is an attractive strategy for global warming mitigation and resource utilization. However, converting CO2 to ethanol remains great challenge due to the low activity, poor product selectivity and stability of electrocatalysts. Here, the B‐ and N‐co‐doped nanodiamond (BND) was reported as an efficient and stable electrode for selective reduction of CO2 to ethanol. Good ethanol selectivity was achieved on the BND with high Faradaic efficiency of 93.2 % (−1.0 V vs. RHE), which overcame the limitation of low selectivity for multicarbon or high heating value fuels. Its superior performance was mainly originated from the synergistic effect of B and N co‐doping, high N content and overpotential for hydrogen evolution. The possible pathway for CO2 reduction revealed by DFT computation was CO2→*COOH→*CO→*COCO→*COCH2OH→*CH2OCH2OH→CH3CH2OH. 相似文献
7.
MoP Nanoparticles Supported on Indium‐Doped Porous Carbon: Outstanding Catalysts for Highly Efficient CO2 Electroreduction 下载免费PDF全文
Xiaofu Sun Lu Lu Dr. Qinggong Zhu Dr. Congyi Wu Dexin Yang Chunjun Chen Prof. Dr. Buxing Han 《Angewandte Chemie (International ed. in English)》2018,57(9):2427-2431
Electrochemical reduction of CO2 into value‐added product is an interesting area. MoP nanoparticles supported on porous carbon were synthesized using metal–organic frameworks as the carbon precursor, and initial work on CO2 electroreduction using the MoP‐based catalyst were carried out. It was discovered that MoP nanoparticles supported on In‐doped porous carbon had outstanding performance for CO2 reduction to formic acid. The Faradaic efficiency and current density could reach 96.5 % and 43.8 mA cm?2, respectively, when using ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate as the supporting electrolyte. The current density is higher than those reported up to date with very high Faradaic efficiency. The MoP nanoparticles and the doped In2O3 cooperated very well in catalyzing the CO2 electroreduction. 相似文献
8.
Juan Du Shaopeng Li Shulin Liu Yu Xin Bingfeng Chen Huizhen Liu Buxing Han 《Chemical science》2020,11(19):5098
Efficient electroreduction of carbon dioxide (CO2) to ethanol is of great importance, but remains a challenge because it involves the transfer of multiple proton–electron pairs and carbon–carbon coupling. Herein, we report a CoO-anchored N-doped carbon material composed of mesoporous carbon (MC) and carbon nanotubes (CNT) as a catalyst for CO2 electroreduction. The faradaic efficiencies of ethanol and current density reached 60.1% and 5.1 mA cm−2, respectively. Moreover, the selectivity for ethanol products was extremely high among the products produced from CO2. A proposed mechanism is discussed in which the MC–CNT/Co catalyst provides a relay catalytic platform, where CoO catalyzes the formation of CO* intermediates which spill over to MC–CNT for carbon–carbon coupling to form ethanol. The high selectivity for ethanol is attributed mainly to the highly selective carbon–carbon coupling active sites on MC–CNT.The relay catalytic platform is very efficient and selective for CO2 electroreduction to ethanol. 相似文献
9.
Regulation of Coordination Number over Single Co Sites: Triggering the Efficient Electroreduction of CO2 下载免费PDF全文
Xiaoqian Wang Zhao Chen Xuyan Zhao Prof. Tao Yao Prof. Wenxing Chen Prof. Rui You Changming Zhao Geng Wu Jing Wang Prof. Weixin Huang Prof. Jinlong Yang Prof. Xun Hong Prof. Shiqiang Wei Prof. Yuen Wu Prof. Yadong Li 《Angewandte Chemie (International ed. in English)》2018,57(7):1944-1948
The design of active, selective, and stable CO2 reduction electrocatalysts is still challenging. A series of atomically dispersed Co catalysts with different nitrogen coordination numbers were prepared and their CO2 electroreduction catalytic performance was explored. The best catalyst, atomically dispersed Co with two‐coordinate nitrogen atoms, achieves both high selectivity and superior activity with 94 % CO formation Faradaic efficiency and a current density of 18.1 mA cm?2 at an overpotential of 520 mV. The CO formation turnover frequency reaches a record value of 18 200 h?1, surpassing most reported metal‐based catalysts under comparable conditions. Our experimental and theoretical results demonstrate that lower a coordination number facilitates activation of CO2 to the CO2.? intermediate and hence enhances CO2 electroreduction activity. 相似文献
10.
Jinze Liu Yating Wang Hao Jiang Haibo Jiang Xiaodong Zhou Yuhang Li Chunzhong Li 《化学:亚洲杂志》2020,15(3):425-431
Electrochemical reduction of carbon dioxide (CO2) to CO is regarded as an efficient method to utilize the greenhouse gas CO2, because the CO product can be further converted into high value‐added chemicals via the Fisher–Tropsch process. Among all electrocatalysts used for CO2‐to‐CO reduction, Au‐based catalysts have been demonstrated to possess high selectivity, but their precious price limits their future large‐scale applications. Thus, simultaneously achieving high selectivity and reasonable price is of great importance for the development of Au‐based catalysts. Here, we report Ag@Au core–shell nanowires as electrocatalyst for CO2 reduction, in which a nanometer‐thick Au film is uniformly deposited on the core Ag nanowire. Importantly, the Ag@Au catalyst with a relative low Au content can drive CO generation with nearly 100 % Faraday efficiency in 0.1 m KCl electrolyte at an overpotential of ca. ?1.0 V. This high selectivity of CO2 reduction could be attributed to a suitable adsorption strength for the key intermediate on Au film together with the synergistic effects between the Au shell and Ag core and the strong interaction between CO2 and Cl? ions in the electrolyte, which may further pave the way for the development of high‐efficiency electrocatalysts for CO2 reduction. 相似文献
11.
Dunfeng Gao Ilya Sinev Fabian Scholten Rosa M. Arn‐Ais Nuria J. Divins Kristina Kvashnina Janis Timoshenko Beatriz Roldan Cuenya 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(47):17203-17209
Production of multicarbon products (C2+) from CO2 electroreduction reaction (CO2RR) is highly desirable for storing renewable energy and reducing carbon emission. The electrochemical synthesis of CO2RR catalysts that are highly selective for C2+ products via electrolyte‐driven nanostructuring is presented. Nanostructured Cu catalysts synthesized in the presence of specific anions selectively convert CO2 into ethylene and multicarbon alcohols in aqueous 0.1 m KHCO3 solution, with the iodine‐modified catalyst displaying the highest Faradaic efficiency of 80 % and a partial geometric current density of ca. 31.2 mA cm?2 for C2+ products at ?0.9 V vs. RHE. Operando X‐ray absorption spectroscopy and quasi in situ X‐ray photoelectron spectroscopy measurements revealed that the high C2+ selectivity of these nanostructured Cu catalysts can be attributed to the highly roughened surface morphology induced by the synthesis, presence of subsurface oxygen and Cu+ species, and the adsorbed halides. 相似文献
12.
Metal‐Doped Nitrogenated Carbon as an Efficient Catalyst for Direct CO2 Electroreduction to CO and Hydrocarbons 下载免费PDF全文
Dr. Ana Sofia Varela Dr. Nastaran Ranjbar Sahraie Julian Steinberg Wen Ju Dr. Hyung‐Suk Oh Prof. Dr. Peter Strasser 《Angewandte Chemie (International ed. in English)》2015,54(37):10758-10762
This study explores the kinetics, mechanism, and active sites of the CO2 electroreduction reaction (CO2RR) to syngas and hydrocarbons on a class of functionalized solid carbon‐based catalysts. Commercial carbon blacks were functionalized with nitrogen and Fe and/or Mn ions using pyrolysis and acid leaching. The resulting solid powder catalysts were found to be active and highly CO selective electrocatalysts in the electroreduction of CO2 to CO/H2 mixtures outperforming a low‐area polycrystalline gold benchmark. Unspecific with respect to the nature of the metal, CO production is believed to occur on nitrogen functionalities in competition with hydrogen evolution. Evidence is provided that sufficiently strong interaction between CO and the metal enables the protonation of CO and the formation of hydrocarbons. Our results highlight a promising new class of low‐cost, abundant electrocatalysts for synthetic fuel production from CO2. 相似文献
13.
David M. Koshy Shucheng Chen Dong Un Lee Michaela Burke Stevens Ahmed M. Abdellah Samuel M. Dull Gan Chen Dennis Nordlund Alessandro Gallo Christopher Hahn Drew C. Higgins Zhenan Bao Thomas F. Jaramillo 《Angewandte Chemie (International ed. in English)》2020,59(10):4043-4050
Ni,N‐doped carbon catalysts have shown promising catalytic performance for CO2 electroreduction (CO2R) to CO; this activity has often been attributed to the presence of nitrogen‐coordinated, single Ni atom active sites. However, experimentally confirming Ni?N bonding and correlating CO2 reduction (CO2R) activity to these species has remained a fundamental challenge. We synthesized polyacrylonitrile‐derived Ni,N‐doped carbon electrocatalysts (Ni‐PACN) with a range of pyrolysis temperatures and Ni loadings and correlated their electrochemical activity with extensive physiochemical characterization to rigorously address the origin of activity in these materials. We found that the CO2R to CO partial current density increased with increased Ni content before plateauing at 2 wt % which suggests a dispersed Ni active site. These dispersed active sites were investigated by hard and soft X‐ray spectroscopy, which revealed that pyrrolic nitrogen ligands selectively bind Ni atoms in a distorted square‐planar geometry that strongly resembles the active sites of molecular metal–porphyrin catalysts. 相似文献
14.
Keqiang Xu Jinhan Li Fangming Liu Xijie Chen Tete Zhao Fangyi Cheng 《Angewandte Chemie (International ed. in English)》2023,62(50):e202311968
The large-scale deployment of CO2 electroreduction is hampered by deficient carbon utilization in neutral and alkaline electrolytes due to CO2 loss into (bi)carbonates. Switching to acidic media mitigates carbonation, but suffers from low product selectivity because of hydrogen evolution. Here we report a crown ether decoration strategy on a Cu catalyst to enhance carbon utilization and selectivity of CO2 methanation under acidic conditions. Macrocyclic 18-Crown-6 is found to enrich potassium cations near the Cu electrode surface, simultaneously enhancing the interfacial electric field to stabilize the *CO intermediate and accelerate water dissociation to boost *CO protonation. Remarkably, the mixture of 18-Crown-6 and Cu nanoparticles affords a CH4 Faradaic efficiency of 51.2 % and a single pass carbon efficiency of 43.0 % toward CO2 electroreduction in electrolyte with pH=2. This study provides a facile strategy to promote CH4 selectivity and carbon utilization by modifying Cu catalysts with supramolecules. 相似文献
15.
Ting Wang Hong Ma Xin Liu Yang Luo Shujing Zhang Yuxia Sun Xinhong Wang Jin Gao Jie Xu 《化学:亚洲杂志》2019,14(9):1515-1522
It is an attractive and challenging topic to endow non‐noble metal catalysts with high efficiency via a nitrogen‐doping approach. In this study, a nitrogen‐doped carbon catalyst with high nitrogen content encapsulating cobalt NPs (CoOx@N‐C(g)) was synthesized, and characterized in detail by XRD, HRTEM, N2‐physisorption, ICP, CO2‐TPD, and XPS techniques. g‐C3N4 nanosheets act as nitrogen source and self‐sacrificing templates, giving rise to an ultrahigh nitrogen content of 14.0 %, much higher than those using bulk g‐C3N4 (4.4 %) via the same synthesis procedures. As a result, CoOx@N‐C(g) exhibited the highest performance in the oxidative esterification of biomass‐derived platform furfural to methylfuroate under base‐free conditions, achieving 95.0 % conversion and 97.1 % selectivity toward methylfuroate under 0.5 MPa O2 at 100 °C for 6 h, far exceeding those of other cobalt‐based catalysts. The high efficiency of CoOx@N‐C(g) was closely related to its high ratio of pyridinic nitrogen species that may act as Lewis basic sites as well as its capacity for the activation of dioxygen to superoxide radical O2.?. 相似文献
16.
Electrochemical Reduction of Carbon Dioxide to Methanol on Hierarchical Pd/SnO2 Nanosheets with Abundant Pd–O–Sn Interfaces 下载免费PDF全文
Wuyong Zhang Qing Qin Dr. Lei Dai Ruixuan Qin Dr. Xiaojing Zhao Xumao Chen Daohui Ou Dr. Jie Chen Dr. Tracy T Chuong Prof. Binghui Wu Prof. Nanfeng Zheng 《Angewandte Chemie (International ed. in English)》2018,57(30):9475-9479
Electrochemical conversion of CO2 into fuels using electricity generated from renewable sources helps to create an artificial carbon cycle. However, the low efficiency and poor stability hinder the practical use of most conventional electrocatalysts. In this work, a 2D hierarchical Pd/SnO2 structure, ultrathin Pd nanosheets partially capped by SnO2 nanoparticles, is designed to enable multi‐electron transfer for selective electroreduction of CO2 into CH3OH. Such a structure design not only enhances the adsorption of CO2 on SnO2, but also weakens the binding strength of CO on Pd due to the as‐built Pd–O–Sn interfaces, which is demonstrated to be critical to improve the electrocatalytic selectivity and stability of Pd catalysts. This work provides a new strategy to improve electrochemical performance of metal‐based catalysts by creating metal oxide interfaces for selective electroreduction of CO2. 相似文献
17.
Hong Phong Duong Dr. Jose Guillermo Rivera de la Cruz Dr. Ngoc-Huan Tran Jacques Louis Dr. Sandrine Zanna Dr. David Portehault Dr. Andrea Zitolo Dr. Michael Walls Dr. Deizi Vanessa Peron Dr. Moritz W. Schreiber Prof. Nicolas Menguy Prof. Marc Fontecave 《Angewandte Chemie (International ed. in English)》2023,62(49):e202310788
The need of carbon sources for the chemical industry, alternative to fossil sources, has pointed to CO2 as a possible feedstock. While CO2 electroreduction (CO2R) allows production of interesting organic compounds, it suffers from large carbon losses, mainly due to carbonate formation. This is why, quite recently, tandem CO2R, a two-step process, with first CO2R 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. 相似文献
18.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(40):12387-12391
Conversion of carbon dioxide (CO2) into fuels and chemicals by electroreduction has attracted significant interest, although it suffers from a large overpotential and low selectivity. A Pd‐Sn alloy electrocatalyst was developed for the exclusive conversion of CO2 into formic acid in an aqueous solution. This catalyst showed a nearly perfect faradaic efficiency toward formic acid formation at the very low overpotential of −0.26 V, where both CO formation and hydrogen evolution were completely suppressed. Density functional theory (DFT) calculations suggested that the formation of the key reaction intermediate HCOO* as well as the product formic acid was the most favorable over the Pd‐Sn alloy catalyst surface with an atomic composition of PdSnO2, consistent with experiments. 相似文献
19.
Qihao Yang Chun‐Chuen Yang Chia‐Her Lin Hai‐Long Jiang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(11):3549-3553
The development of efficient and low energy‐consumption catalysts for CO2 conversion is desired, yet remains a great challenge. Herein, a class of novel hollow porous carbons (HPC), featuring well dispersed dopants of nitrogen and single Zn atoms, have been fabricated, based on the templated growth of a hollow metal–organic framework precursor, followed by pyrolysis. The optimized HPC‐800 achieves efficient catalytic CO2 cycloaddition with epoxides, under light irradiation, at ambient temperature, by taking advantage of an ultrahigh loading of (11.3 wt %) single‐atom Zn and uniform N active sites, high‐efficiency photothermal conversion as well as the hierarchical pores in the carbon shell. As far as we know, this is the first report on the integration of the photothermal effect of carbon‐based materials with single metal atoms for catalytic CO2 fixation. 相似文献
20.
Synthesis of High‐Surface‐Area Nitrogen‐Doped Porous Carbon Microflowers and Their Efficient Carbon Dioxide Capture Performance 下载免费PDF全文
Sustainable carbon materials have received particular attention in CO2 capture and storage owing to their abundant pore structures and controllable pore parameters. Here, we report high‐surface‐area hierarchically porous N‐doped carbon microflowers, which were assembled from porous nanosheets by a three‐step route: soft‐template‐assisted self‐assembly, thermal decomposition, and KOH activation. The hydrazine hydrate used in our experiment serves as not only a nitrogen source, but also a structure‐directing agent. The activation process was carried out under low (KOH/carbon=2), mild (KOH/carbon=4) and severe (KOH/carbon=6) activation conditions. The mild activated N‐doped carbon microflowers (A‐NCF‐4) have a hierarchically porous structure, high specific surface area (2309 m2 g?1), desirable micropore size below 1 nm, and importantly large micropore volume (0.95 cm3 g?1). The remarkably high CO2 adsorption capacities of 6.52 and 19.32 mmol g?1 were achieved with this sample at 0 °C (273 K) and two pressures, 1 bar and 20 bar, respectively. Furthermore, this sample also exhibits excellent stability during cyclic operations and good separation selectivity for CO2 over N2. 相似文献