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1.
Guanghui Feng Prof. Wei Chen Baiyin Wang Dr. Yanfang Song Guihua Li Prof. Jianhui Fang Prof. Wei Wei Prof. Yuhan Sun 《化学:亚洲杂志》2018,13(16):1992-2008
Electrochemical reduction of carbon dioxide (CO2) driven by renewable electricity to give chemicals and fuels is considered an ideal approach that can alleviate both carbon emission and energy tension stress. High‐value chemicals such as oxygenates can be effectively produced from the electroreduction of CO2, and this is highly attractive to promote the economy and applicability of CO2 utilization. This review focuses on recent advancements in the electrochemical reduction of CO2 to formic acid, methanol, ethanol, acetic acid, and other oxygenates. The principles of the process, influencing factors, and typical catalysts are summarized. On the basis of the aforementioned discussions, we present future prospects for further development of the electroreduction of CO2 to oxygenates. 相似文献
2.
Prof. Frédéric‐Georges Fontaine Marc‐André Courtemanche Marc‐André Légaré 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(11):2990-2996
Metal‐free systems, including frustrated Lewis pairs (FLPs) have been shown to bind CO2. By reducing the Lewis acidity and basicity of the ambiphilic system, it is possible to generate active catalysts for the deoxygenative hydroboration of carbon dioxide to methanol derivatives with conversion rates comparable to those of transition‐metal‐based catalysts. 相似文献
3.
Louisa Rui Lin Ting Dr. Rodrigo García-Muelas Dr. Antonio J. Martín Florentine L. P. Veenstra Stuart Tze-Jin Chen Yujie Peng Edwin Yu Xuan Per Sergio Pablo-García Prof. Dr. Núria López Prof. Dr. Javier Pérez-Ramírez Prof. Dr. Boon Siang Yeo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(47):21258-21265
The electroreduction of carbon dioxide using renewable electricity is an appealing strategy for the sustainable synthesis of chemicals and fuels. Extensive research has focused on the production of ethylene, ethanol and n-propanol, but more complex C4 molecules have been scarcely reported. Herein, we report the first direct electroreduction of CO2 to 1-butanol in alkaline electrolyte on Cu gas diffusion electrodes (Faradaic efficiency=0.056 %, j1-Butanol=−0.080 mA cm−2 at −0.48 V vs. RHE) and elucidate its formation mechanism. Electrolysis of possible molecular intermediates, coupled with density functional theory, led us to propose that CO2 first electroreduces to acetaldehyde-a key C2 intermediate to 1-butanol. Acetaldehyde then undergoes a base-catalyzed aldol condensation to give crotonaldehyde via electrochemical promotion by the catalyst surface. Crotonaldehyde is subsequently electroreduced to butanal, and then to 1-butanol. In a broad context, our results point to the relevance of coupling chemical and electrochemical processes for the synthesis of higher molecular weight products from CO2. 相似文献
4.
Isolation of a Neutral Boron‐Containing Radical Stabilized by a Cyclic (Alkyl)(Amino)Carbene 下载免费PDF全文
Dr. Philipp Bissinger Prof. Dr. Holger Braunschweig Dr. Alexander Damme Dr. Ivo Krummenacher Dr. Ashwini K. Phukan Dr. Krzysztof Radacki Shun Sugawara 《Angewandte Chemie (International ed. in English)》2014,53(28):7360-7363
Utilizing a cyclic (alkyl)(amino)carbene (CAAC) as a ligand, neutral CAAC‐stabilized radicals containing a boryl functionality could be prepared by reduction of the corresponding haloborane adducts. The radical species with a duryl substituent was fully characterized by single‐crystal X‐ray structural analysis, EPR spectroscopy, and DFT calculations. Compared to known neutral boryl radicals, the isolated radical species showed larger spin density on the boron atom. Furthermore, the compound that was isolated is extraordinarily stable to high temperatures under inert conditions, both in solution and in the solid state. Electrochemical investigations of the radical suggest the possibility to generate a stable formal boryl anion species. 相似文献
5.
Dr. Robert Kretschmer David A. Ruiz Dr. Curtis E. Moore Prof. Dr. Arnold L. Rheingold Prof. Dr. Guy Bertrand 《Angewandte Chemie (International ed. in English)》2014,53(31):8176-8179
A cyclic alkyl(amino)carbene readily reacts with SbCl3 to form the corresponding SbIII adduct. One‐electron reduction gives rise to the first example of a neutral antimony‐centered radical characterized in solution. Two‐electron reduction affords a Lewis base stabilized chloro‐stibinidene, whereas three‐electron reduction gives an antimony diatomic species capped by two carbenes. The radical has been characterized by EPR spectroscopy, while the structure of the other three species has been ascertained by single‐crystal X‐ray diffraction. In these four species, the formal oxidation state of the metalloid diminishes from III, to II, to I, and finally 0. 相似文献
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7.
Similarly to NHCs, CAACa and BACa react with CO2 to give the corresponding betaines. Based on the carbonyl stretching frequencies of cis‐[RhCl(CO)2(L)] complexes, the order of electron donor ability was predicted to be CAACa≈BACa>NHCs. When the betaines νasym(CO2) values are used, the apparent ordering is BACa>NHCs≈CAACa that indicates a limitation for the use of IR spectroscopy in the ranking of ligand σ‐donating ability. Although all carbenes react with carbon disulfide to give the corresponding betaines, a second equivalent of CS2 reacts with the BAC‐CS2 leading to a bicyclic thieno[2,3‐diamino]‐1,3‐dithiole‐2‐thione, which results from a novel ring expansion process. Surprisingly, in contrast to NHCs, CAAC a does not react with carbodiimide, whereas BACa exclusively gives a ring expanded product, analogous to that obtained with CS2. The intermediate amidinate can be trapped, using the lithium tetrafluoroborate adduct of BACb as a carbene surrogate. 相似文献
8.
二氧化碳浓度持续升高导致的温室效应已在全球范围内引发极端天气、冰川融化等一系列生态环境问题。为降低二氧化碳含量,改善气候变暖带来的恶劣影响,研发高效、绿色、安全的二氧化碳处理技术,促进碳资源循环可持续发展刻不容缓。熔盐离子液体作为一种良好的电化学转化介质,为二氧化碳还原提供了一条极具应用前景的技术路线。综述了国内外近几年高温熔盐中二氧化碳的捕获与电化学还原的研究,简述了熔盐电沉积碳的电化学机理和热力学机制,对不同形貌高附加值碳材料:无定形碳、碳球和碳纳米管的制备进行了总结,最后对未来发展方向做出展望。 相似文献
9.
Zeyu Han Prof. Dr. Derek P. Gates 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(59):14594-14599
The catalytic metathesis of C=C bonds is a textbook reaction that has no parallel in the widely studied area of multiple bonds involving heavier p-block elements. A high-yielding P=C bond metathesis of phosphaalkenes (ArP=CPh2, Ar=Mes, o-Tol, Ph) has been discovered that is catalyzed by N-heterocyclic carbenes (NHC=Me2IMe, Me2IiPr). The products are cyclic oligomers formally derived from ArP=PAr [i. e. cyclo-(ArP)n; n=3, 4, 5, 6] and Ph2C=CPh2. Preliminary mechanistic studies of this remarkable transformation have established NHC=PAr (Ar=Mes, o-Tol, Ph) as key phosphinidene transfer agents. In addition, novel cyclic intermediates, such as, cyclo-(ArP)2CPh2 and cyclo-(ArP)4CPh2 have also been observed. This work represents a rare application of non-metal-based catalysts for transformations involving main-group elements. 相似文献
10.
Xiao-Fang BAI Wei CHEN Bai-Yin WANG Guang-Hui FENG Wei WEI Zheng JIAO Yu-Han SUN 《物理化学学报》2017,33(12):2388-2403
利用低品阶的可再生电能,将二氧化碳(CO_2)电化学还原生成高附加值的化学品或燃料,既可以变废为宝、减少CO_2排放,又能将可再生能源转变为高能量密度的燃料储存,具有重要的现实意义。电化学还原CO_2的研究,是目前世界范围内的研究热点,许多标志性的重要研究成果不断涌现。本文首先简要介绍了CO_2电化学还原的基本原理,然后概述了近5年来在其电催化剂材料和反应机理相关的实验与理论研究方面的昀新研究进展,昀后对其发展趋势进行了展望。 相似文献
11.
《Angewandte Chemie (International ed. in English)》2017,56(34):10046-10068
Discovered in 2005, cyclic (alkyl)(amino)carbenes (CAACs) are among the most nucleophilic (σ donating) and also electrophilic (π‐accepting) stable carbenes known to date. These properties allow them to activate a variety of small molecules and enthalpically strong bonds, to stabilize highly reactive main‐group and transition‐metal diamagnetic and paramagnetic species, and to bind strongly to metal centers, which gives rise to very robust catalysts. The most important results published up to the end of 2013 are briefly summarized, while the majority of this Review focuses on findings reported within the last three years. 相似文献
12.
《中国化学》2018,36(7):644-659
In the last few years, photochemical and electrochemical CO2 transformations have attracted increasing attention in response to topical interest in renewable energy and green chemistry. The present minireview offers an overview about the current approaches for the photochemical and electrochemical carbon dioxide fixation with organic compounds. Valuable products, including carboxylic acids and heterocyclic compounds, are accessible through carboxylation and carboxylative cyclization, respectively. In photochemical and electrochemical processes, photo‐ or electro‐induced radical ions or other high‐energy organic compounds are considered as key intermediates to react with CO2. Besides, activation of CO2 to produce radical anion has also been reported. 相似文献
13.
Kirill V. Kholin Mikhail N. Khrizanforov Vasily M. Babaev Guliya R. Nizameeva Salima T. Minzanova Marsil K. Kadirov Yulia H. Budnikova 《Molecules (Basel, Switzerland)》2021,26(18)
A selective noble-metal-free molecular catalyst has emerged as a fruitful approach in the quest for designing efficient and stable catalytic materials for CO2 reduction. In this work, we report that a sodium pectate complex of copper (PG-NaCu) proved to be highly active in the electrocatalytic conversion of CO2 to CH4 in water. Stability and selectivity of conversion of CO2 to CH4 as a product at a glassy carbon electrode were discovered. The copper complex PG-NaCu was synthesized and characterized by physicochemical methods. The electrochemical CO2 reduction reaction (CO2RR) proceeds at −1.5 V vs. Ag/AgCl at ~10 mA/cm2 current densities in the presence of the catalyst. The current density decreases by less than 20% within 12 h of electrolysis (the main decrease occurs in the first 3 h of electrolysis in the presence of CO2). This copper pectate complex (PG-NaCu) combines the advantages of heterogeneous and homogeneous catalysts, the stability of heterogeneous solid materials and the performance (high activity and selectivity) of molecular catalysts. 相似文献
14.
Austin Chipojola Mtukula Xiang-Da Zhang Shu-Zhen Hou Jian-Mei Huang Dr. Ming Xu Prof. Dr. Zhi-Yuan Gu 《欧洲无机化学杂志》2023,26(21):e202300170
The large concentration of carbon dioxide (CO2) in the atmosphere can be utilized in industrial production using effective electrocatalysts such as metal-organic frameworks (MOFs). Due to good properties such as high surface area, designable functionality, and uniform constitution, MOFs are regarded as promising electrocatalysts for the carbon dioxide electrochemical reduction reaction (eCO2RR). This review covers the importance, challenges, and mechanism of eCO2RR, and simply discusses the progress in the synthesis methods and characterization of MOFs. The review also thoroughly discusses the advances of single metal-based MOFs, mixed metal-based MOFs, and MOF derivatives as electrocatalysts for efficient eCO2RR. 相似文献
15.
研究了Sn气体扩散电极(SGDE)上电化学还原CO2制甲酸(ERCF)性能的稳定性。采用X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线能量色散谱(EDX)和活性表面积测试等技术手段 分别表征SGDE在电化学还原CO2制甲酸过程前后的物相结构、表面形貌、元素组成和活性表面积。 采用生成甲酸的法拉第效率(fHCOOH)评价SGDE上电化学还原CO2制甲酸的性能。 结果显示,fHCOOH随电解时间的延长急剧地降低,电解时间12 h的fHCOOH((36.6±1.6)%)比电解时间0.5 h时的fHCOOH((78.5±0.1)%)降低了53%。 SGDE在12 h电还原反应后,表面沉积了微量Fe,而且Sn含量(质量分数)减少了66%,活性表面积降低了41%。 进一步的研究发现,沉积的微量Fe对电化学还原CO2制甲酸过程基本没有影响,Sn含量和活性表面积的降低可能是SGDE上电化学还原CO2制甲酸性能降低的主要原因。 相似文献
16.
Alexander M. Khenkin Dr. Irena Efremenko Dr. Lev Weiner Dr. Jan M. L. Martin Prof. Ronny Neumann Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(4):1356-1364
A polyoxometalate of the Keggin structure substituted with RuIII, 6Q5[RuIII(H2O)SiW11O39] in which 6Q=(C6H13)4N+, catalyzed the photoreduction of CO2 to CO with tertiary amines, preferentially Et3N, as reducing agents. A study of the coordination of CO2 to 6Q5[RuIII(H2O)SiW11O39] showed that 1) upon addition of CO2 the UV/Vis spectrum changed, 2) a rhombic signal was obtained in the EPR spectrum (gx=2.146, gy=2.100, and gz=1.935), and 3) the 13C NMR spectrum had a broadened peak of bound CO2 at 105.78 ppm (Δ1/2=122 Hz). It was concluded that CO2 coordinates to the RuIII active site in both the presence and absence of Et3N to yield 6Q5[RuIII(CO2)SiW11O39]. Electrochemical measurements showed the reduction of RuIII to RuII in 6Q5[RuIII(CO2)SiW11O39] at ?0.31 V versus SCE, but no such reduction was observed for 6Q5[RuIII(H2O)SiW11O39]. DFT‐calculated geometries optimized at the M06/PC1//PBE/AUG‐PC1//PBE/PC1‐DF level of theory showed that CO2 is preferably coordinated in a side‐on manner to RuIII in the polyoxometalate through formation of a Ru? O bond, further stabilized by the interaction of the electrophilic carbon atom of CO2 to an oxygen atom of the polyoxometalate. The end‐on CO2 bonding to RuIII is energetically less favorable but CO2 is considerably bent, thus favoring nucleophilic attack at the carbon atom and thereby stabilizing the carbon sp2 hybridization state. Formation of a O2C–NMe3 zwitterion, in turn, causes bending of CO2 and enhances the carbon sp2 hybridization. The synergetic effect of these two interactions stabilizes both Ru–O and C–N interactions and probably determines the promotional effect of an amine on the activation of CO2 by [RuIII(H2O)SiW11O39]5?. Electronic structure analysis showed that the polyoxometalate takes part in the activation of both CO2 and Et3N. A mechanistic pathway for photoreduction of CO2 is suggested based on the experimental and computed results. 相似文献
17.
Isolation of an Imino‐N‐heterocyclic Carbene/Germanium(0) Adduct: A Mesoionic Germylene Equivalent 下载免费PDF全文
Bochao Su Dr. Rakesh Ganguly Dr. Yongxin Li Prof. Dr. Rei Kinjo 《Angewandte Chemie (International ed. in English)》2014,53(48):13106-13109
An autoionization of germanium dichloride/dioxane complex with an imino‐N‐heterocyclic carbene ligand ( L ) afforded a novel germyliumylidene ion, [( L )GeCl]+[GeCl3]?, which was fully characterized. Reduction of the germyliumylidene ion with potassium graphite produced a cyclic species [( L )Ge], which can be viewed as both a Ge0 species and a mesoionic germylene. X‐ray diffraction analysis and computational studies revealed one of the lone pairs on the Ge atom is involved in the π system on the GeC2N2 five‐membered ring. It was also confirmed that the nucleophilic behavior of [( L )Ge] as a two lone‐pair donor. 相似文献
18.
Steffen Styra Dr. Mohand Melaimi Dr. Curtis E. Moore Prof. Arnold. L. Rheingold Timo Augenstein Prof. Dr. Frank Breher Prof. Guy Bertrand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(23):8441-8446
A stable cyclic (alkyl)(amino)carbene (CAAC) 1 inserts into the para‐CF bond of pentafluoropyridine, and after fluoride abstraction, the iminium‐pyridyl adduct [ 3 ]+ was isolated. A cyclic voltammetry study shows a reversible three‐state redox system involving [ 3 ]+, [ 3 ] ? , and [ 3 ] ? . The CAAC‐pyridyl radical [ 3 ] ? , obtained by reduction of [ 3 ]+ with magnesium, has been spectroscopically and crystallographically characterized. In contrast to the lack of π communication between the CAAC and the pyridine units in cation [ 3 ]+, the unpaired electron of [ 3 ] ? is delocalized over an extended π system involving both heterocycles. 相似文献
19.
Rapid Selective Electrocatalytic Reduction of Carbon Dioxide to Formate by an Iridium Pincer Catalyst Immobilized on Carbon Nanotube Electrodes 下载免费PDF全文
Dr. Peng Kang Dr. Sheng Zhang Prof. Thomas J. Meyer Prof. Maurice Brookhart 《Angewandte Chemie (International ed. in English)》2014,53(33):8709-8713
An iridium pincer dihydride catalyst was immobilized on carbon nanotube‐coated gas diffusion electrodes (GDEs) by using a non‐covalent binding strategy. The as‐prepared GDEs are efficient, selective, durable, gas permeable electrodes for electrocatalytic reduction of CO2 to formate. High turnover numbers (ca. 54 000) and turnover frequencies (ca. 15 s?1) were enabled by the novel electrode architecture in aqueous solutions saturated in CO2 with added HCO3?. 相似文献
20.
The electrochemical reduction of carbon dioxide (CO2) to value‐added products obtains great attention and investigation worldwide in recent years. The commercialization of this green process relies on the progress of relating high‐performance electrocatalysts and their feasibility with proper reactor design. The microbial electrosynthesis (MES) is an alternative route to reduce CO2 with electroactive bio‐film electrode as catalyst. This review presents the research status and development of cathode catalysts, particularly focusing on the active sites and development tendency, for highly efficient electrochemical reduction CO2 from personal viewpoint. Some of our results are also presented to exhibit contributions. MES shows a similar process to the typical electrochemical reduction of CO2. Their combination is an important trend, and the future research in this field is full of challenges and opportunities. 相似文献