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1.
Shufang Ji Prof. Yang Qu Dr. Tao Wang Yuanjun Chen Prof. Guofeng Wang Xue Li Dr. Juncai Dong QiuYu Chen Wanying Zhang Zedong Zhang Shiyou Liang Prof. Rong Yu Dr. Yu Wang Prof. Dingsheng Wang Prof. Yadong Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(26):10738-10744
The solar-driven photocatalytic reduction of CO2 (CO2RR) into chemical fuels is a promising route to enrich energy supplies and mitigate CO2 emissions. However, low catalytic efficiency and poor selectivity, especially in a pure-water system, hinder the development of photocatalytic CO2RR owing to the lack of effective catalysts. Herein, we report a novel atom-confinement and coordination (ACC) strategy to achieve the synthesis of rare-earth single erbium (Er) atoms supported on carbon nitride nanotubes (Er1/CN-NT) with a tunable dispersion density of single atoms. Er1/CN-NT is a highly efficient and robust photocatalyst that exhibits outstanding CO2RR performance in a pure-water system. Experimental results and density functional theory calculations reveal the crucial role of single Er atoms in promoting photocatalytic CO2RR. 相似文献
2.
Dr. Panagiotis Trogadas Linlin Xu Prof. Marc-Olivier Coppens 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(1):e202314446
The electrochemical reduction of CO2 (CO2RR) is a promising approach to maintain a carbon cycle balance and produce value-added chemicals. However, CO2RR technology is far from mature, since the conventional CO2RR electrocatalysts suffer from low activity (leading to currents <10 mA cm−2 in an H-cell), stability (<120 h), and selectivity. Hence, they cannot meet the requirements for commercial applications (>200 mA cm−2, >8000 h, >90 % selectivity). Significant improvements are possible by taking inspiration from nature, considering biological organisms that efficiently catalyze the CO2 to various products. In this minireview, we present recent examples of enzyme-inspired and enzyme-mimicking CO2RR electrocatalysts enabling the production of C1 products with high faradaic efficiency (FE). At present, these designs do not typically follow a methodical approach, but rather focus on isolated features of biological systems. To achieve disruptive change, we advocate a systematic design methodology that leverages fundamental mechanisms associated with desired properties in nature and adapts them to the context of engineering applications. 相似文献
3.
Highly Selective and Stable Reduction of CO2 to CO by a Graphitic Carbon Nitride/Carbon Nanotube Composite Electrocatalyst
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Dr. Xunyu Lu Tze Hao Tan Dr. Yun Hau Ng Prof. Rose Amal 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(34):11991-11996
A stable and selective electrocatalyst for CO2 reduction was fabricated by covalently attaching graphitic carbon nitride onto multiwall carbon nanotubes (g‐C3N4/MWCNTs). The as‐prepared composite is able to reduce CO2 exclusively to CO with a maximum Faraday efficiency of 60 %, and no decay in the catalytic activity was observed even after 50 h of reaction. The enhanced catalytic activity towards CO2 reduction is attributed to the formation of active carbon–nitrogen bonds, high specific surface area, and improved material conductivity of the g‐C3N4/MWCNT composite. 相似文献
4.
Hainan Shi Dr. Saran Long Dr. Jungang Hou Dr. Lu Ye Yanwei Sun Wenjun Ni Dr. Chunshan Song Dr. Keyan Li Dr. Gagik G. Gurzadyan Dr. Xinwen Guo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(19):5028-5035
Fundamental photocatalytic limitations of solar CO2 reduction remain due to low efficiency, serious charge recombination, and short lifetime of catalysts. Herein, two-dimensional graphitic carbon nitride nanosheets with nitrogen vacancies (g-C3Nx) located at both three-coordinate N atoms and uncondensed terminal NHx species were prepared by one-step tartaric acid-assistant thermal polymerization of dicyandiamide. Transient absorption spectra revealed that the defects in g-C3N4 act as trapped states of charges to result in prolonged lifetimes of photoexcited charge carriers. Time-resolved photoluminescence spectroscopy revealed that the faster decay of charges is due to the decreased interlayer stacking distance in g-C3Nx in favor of hopping transition and mobility of charge carriers to the surface of the material. Owing to the synergic virtues of strong visible-light absorption, large surface area, and efficient charge separation, the g-C3Nx nanosheets with negligible loss after 15 h of photocatalysis exhibited a CO evolution rate of 56.9 μmol g−1 h−1 under visible-light irradiation, which is roughly eight times higher than that of pristine g-C3N4. This work presents the role of defects in modulating light absorption and charge separation, which opens an avenue to robust solar-energy conversion performance. 相似文献
5.
工业发展与人类活动导致大气中CO2浓度逐年升高, 引发一系列生态环境问题. 将CO2光催化转化为高附加值化学物质不仅有利于缓解环境压力,也可以带来额外经济价值. 然而, 由于多电子利用效率低和C―C偶联动力学缓慢, 光还原CO2制多碳产品面临产率低和选择性差等挑战. 光催化剂活性位点调控能够有效解决上述问题. 我们综述了近几年用于光还原CO2催化剂表面活性位点设计的研究进展, 主要包括缺陷位点、 金属位点以及掺杂位点等, 从活性位点的角度为光还原CO2催化剂设计提供新视角, 并对开发高效光催化剂具有启发意义. 相似文献
6.
Shufang Ji Yang Qu Tao Wang Yuanjun Chen Guofeng Wang Xue Li Juncai Dong QiuYu Chen Wanying Zhang Zedong Zhang Shiyou Liang Rong Yu Yu Wang Dingsheng Wang Yadong Li 《Angewandte Chemie (International ed. in English)》2020,59(26):10651-10657
The solar‐driven photocatalytic reduction of CO2 (CO2RR) into chemical fuels is a promising route to enrich energy supplies and mitigate CO2 emissions. However, low catalytic efficiency and poor selectivity, especially in a pure‐water system, hinder the development of photocatalytic CO2RR owing to the lack of effective catalysts. Herein, we report a novel atom‐confinement and coordination (ACC) strategy to achieve the synthesis of rare‐earth single erbium (Er) atoms supported on carbon nitride nanotubes (Er1/CN‐NT) with a tunable dispersion density of single atoms. Er1/CN‐NT is a highly efficient and robust photocatalyst that exhibits outstanding CO2RR performance in a pure‐water system. Experimental results and density functional theory calculations reveal the crucial role of single Er atoms in promoting photocatalytic CO2RR. 相似文献
7.
电催化二氧化碳还原(ECR)技术是实现“碳中和”目标的一种理想途径,而过渡金属单原子催化剂具有电子结构可调、原子利用率高和活性位点均一等特点,在ECR研究中具有显著优势。本文首先介绍了单原子电催化剂在还原CO2尤其是在选择性生成CO研究中的优势,然后综述了近年来Fe、Co、Ni及其他单原子电催化剂的反应位点调控策略与电催化选择性的调控机制,重点对质子耦合CO2还原生成CO的中间过程调控进行了归纳总结,并简要展望了发展方向,以期为推动单原子催化剂在ECR中规模化应用提供指导和参考。 相似文献
8.
Yuanyuan Zhang Prof. Jian Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(55):e202201430
Natural photosynthesis is a highly unified biocatalytic system, which coupled cofactor (NAD(P)H) regeneration and enzymatic CO2 reduction efficiently for solar energy conversion. Mimicking nature, a novel system with Rh complex covalently grafted onto NH2-functionalized polymeric carbon nitride (NH2-PCN) was constructed. The integrated connection of the light-harvesting and electron mediation modules as Rhm3-N-PCN could promote the efficient NAD+ reduction to NADH. As a result, the integrated system exhibited a conversion of ∼66 % within 20 minutes. By further coupling in situ generated NADH with formate dehydrogenase (FDH), a photoenzymatic production of formic acid (HCOOH) from CO2 was accomplished. Moreover, by immobilizing FDH onto a hydrophobic membrane, an enhanced HCOOH production of ∼5.0 mM can be obtained due to the concentrated CO2 on the gas-liquid-solid three-phase interface. Our work herein provides an integrated strategy for coupling the anchored electron mediator with immobilized enzyme for enhanced artificial photosynthesis. 相似文献
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10.
Huijun Yu Eynat Haviv Ronny Neumann 《Angewandte Chemie (International ed. in English)》2020,59(15):6219-6223
Research on the photochemical reduction of CO2, initiated already 40 years ago, has with few exceptions been performed by using amines as sacrificial reductants. Hydrocarbons are high‐volume chemicals whose dehydrogenation is of interest, so the coupling of a CO2 photoreduction to a hydrocarbon‐photodehydrogenation reaction seems a worthwhile concept to explore. A three‐component construct was prepared including graphitic carbon nitride (g‐CN) as a visible‐light photoactive semiconductor, a polyoxometalate (POM) that functions as an electron acceptor to improve hole–electron charge separation, and an electron donor to a rhenium‐based CO2 reduction catalyst. Upon photoactivation of g‐CN, a cascade is initiated by dehydrogenation of hydrocarbons coupled to the reduction of the polyoxometalate. Visible‐light photoexcitation of the reduced polyoxometalate enables electron transfer to the rhenium‐based catalyst active for the selective reduction of CO2 to CO. The construct was characterized by zeta potential, IR spectroscopy, thermogravimetry, scanning electron microscopy (SEM) and energy dispersive X‐ray spectroscopy (EDS). An experimental Z‐scheme diagram is presented based on electrochemical measurements and UV/Vis spectroscopy. The conceptual advance should promote study into more active systems. 相似文献
11.
Photocatalytic reduction of CO2 to hydrocarbon compounds is a promising method for addressing energy shortages and environmental pollution. Considerable efforts have been devoted to exploring valid strategies to enhance photocatalytic efficiency. Among various modification methods, the hybridization of different photocatalysts is effective for addressing the shortcomings of a single photocatalyst and enhancing its CO2 reduction performance. In addition, metal-free materials such as g-C3N4 and black phosphorus (BP) are attractive because of their unique structures and electronic properties. Many experimental results have verified the superior photocatalytic activity of a BP/g-C3N4 composite. However, theoretical understanding of the intrinsic mechanism of the activity enhancement is still lacking. Herein, the geometric structures, optical absorption, electronic properties, and CO2 reduction reaction processes of 2D/2D BP/g-C3N4 composite models are investigated using density functional theory calculations. The composite model consists of a monolayer of BP and a tri-s-triazine-based monolayer of g-C3N4. Based on the calculated work function, it is inferred that electrons transfer from g-C3N4 to BP owing to the higher Fermi level of g-C3N4 compared with that of BP. Furthermore, the charge density difference suggests the formation of a built-in electric field at the interface, which is conducive to the separation of photogenerated electron-hole pairs. The optical absorption coefficient demonstrates that the light absorption of the composite is significantly higher than that of its single-component counterpart. Integrated analysis of the band edge potential and interfacial electronic interaction indicates that the migration of photogenerated charge carriers in the BP/g-C3N4 hybrid follows the S-scheme photocatalytic mechanism. Under visible-light irradiation, the photogenerated electrons on BP recombine with the photogenerated holes on g-C3N4, leaving photogenerated electrons and holes in the conduction band of g-C3N4 and the valence band of BP, respectively. Compared with pristine g-C3N4, this S-scheme heterojunction allows efficient separation of photogenerated charge carriers while effectively preserving strong redox abilities. Additionally, the possible reaction path for CO2 reduction on g-C3N4 and BP/g-C3N4 is discussed by computing the free energy of each step. It was found that CO2 reduction on the composite occurs most readily on the g-C3N4 side. The reaction path on the composite is different from that on g-C3N4. The heterojunction reduces the maximum energy barrier for CO2 reduction from 1.48 to 1.22 eV, following the optimal reaction path. Consequently, the BP/g-C3N4 heterojunction is theoretically proven to be an excellent CO2 reduction photocatalyst. This work is helpful for understanding the effect of BP modification on the photocatalytic activity of g-C3N4. It also provides a theoretical basis for the design of other high-performance CO2 reduction photocatalysts.
相似文献
12.
采用过氧化氢氧化法剥离出煤炭结构中的晶体碳[煤基碳点(CDs)], 并通过亚硫酰氯氯化及乙二胺钝化等步骤对其进行氨基化修饰, 制得N, S共掺杂的氨基化煤基碳点(NH2-CDs), 再利用其表面的氨基和含氧基等官能团的配位及分散作用, 将由氯化铜原位还原得到的氧化亚铜(Cu2O)纳米粒子包覆于其中, 制备了复合催化剂Cu2O/NH2-CDs, 表征了其结构和形貌, 并考察了其可见光催化还原CO2/H2O的性能. 结果发现, NH2-CDs的存在使复合催化剂不仅具备了较强的CO2吸附性能, 而且还具有了高效的电子-空穴对分离和电子转移能力, 从而表现出优异的光催化还原CO2制备HCOOH的性能. 反应6 h时, 产物HCOOH的量为2582.4 μmol/g cat, 约为同条件下纯Cu2O作为光催化剂时产物HCOOH产率的7.3倍. 相似文献
13.
Di Niu Cong Wei Zheng Lu Yanyan Fang Bo Liu Da Sun Xiaobin Hao Hongge Pan Gongming Wang 《Molecules (Basel, Switzerland)》2021,26(8)
The electrochemical carbon dioxide reduction reaction (CO2RR) to C2 chemicals has received great attention. Here, we report the cuprous oxide (Cu2O) nanocubes cooperated with silver (Ag) nanoparticles via the replacement reaction for a synergetic CO2RR. The Cu2O-Ag tandem catalyst exhibits an impressive Faradaic efficiency (FE) of 72.85% for C2 products with a partial current density of 243.32 mA·cm−2. The electrochemical experiments and density functional theory (DFT) calculations reveal that the introduction of Ag improves the intermediate CO concentration on the catalyst surface and meanwhile reduces the C-C coupling reaction barrier energy, which is favorable for the synthesis of C2 products. 相似文献
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15.
利用可再生能源将二氧化碳(CO2)电催化还原为有价值的化学品和燃料,不仅可缓解温室效应,而且可实现碳资源的循环利用。以蛋白胨与盐形成的凝胶为原料,经高温热解后制备了用于电还原CO2的Ni-N掺杂碳多孔催化剂。该催化剂表现出优异的电催化还原CO2为CO的性能,在电压为-0.66 V(vs.RHE)下,CO的法拉第效率为92.0%,过电位为550 mV,还原电流密度为2.5 mA·cm-2。该催化剂优异的CO2的电催化活性归因于其存在的Ni-N活性位点和高度多孔的结构。此外,利用太阳能电池产生的电能,该催化剂可持续进行CO2电催化还原为CO,为CO2的资源化利用提供了有价值的参考。 相似文献
16.
LIN Zhi ZHANG Zhengqi WANG Yiqing PENG Zhiming WANG Xinxin WANG Ruizhe HUANG Yu-Cheng MENG Fanqi LI Mingtao DONG Chung-Li ZHANG Qinghua GU Lin SHEN Shaohua 《高等学校化学研究》2022,38(5):1243-1250
Polymeric carbon nitride(PCN) has emerged as a promising candidate for photocatalytic hydrogen evolution, but its dependence on scarce and high-cost noble metal co-catalysts severely limits its extensive application. It will be of great promise to develop non-noble metal single-atom co-catalysts with low-cost and high atom utilization to improve the photocatalytic performance over PCN. Herein, single Ni atoms are successfully anchored onto carbon-vacant PCN nanosheets(CCN-SANi) via a two-step ammonia thermal treatment and photo-deposition process. Theoretical calculations and experimental results demonstrate that the optical absorption property and the charge transfer ability of CCN-SANi have been significantly improved with the introduction of single Ni atoms to form Ni-N3 sites. In comparison to carbon-vacant PCN(CCN) loaded with Ni clusters, the obtained CCN-SANi exhibits 11.4 times increased photocatalytic performance, with the highest hydrogen evolution rate reaching 511 μmol/(g·h), which is even 1.7 times higher than that of CCN loaded with Pt clusters. This research proposes an inspiring and reliable strategy to design novel single-atom semiconducting polymers with electronic structures manipulated for efficient photocatalysis. 相似文献
17.
Prof. Wee-Jun Ong Dr. Lutfi Kurnianditia Putri Prof. Abdul Rahman Mohamed 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(44):9710-9748
Photocatalytic CO2 reduction is a revolutionary approach to solve imminent energy and environmental issues by replicating the ingenuity of nature. The past decade has witnessed an impetus in the rise of two-dimensional (2D) structure materials as advanced nanomaterials to boost photocatalytic activities. In particular, the use of 2D carbon-based materials is deemed as highly favorable, not only as a green material choice, but also due to their exceptional physicochemical and electrical properties. This Review article presents a diverse range of alterations and compositions derived from 2D carbon-based nanomaterials, mainly graphene and graphitic carbon nitride (g-C3N4), which have remarkably ameliorated the photocatalytic CO2 performance. Herein, the rational design of the photocatalyst systems with consideration of the aspect of dimensionality and the resultant heterostructures at the interface are systematically analyzed to elucidate an insightful perspective on this pacey subject. Finally, a conclusion and outlook on the limitations and prospects of the cutting-edge research field are highlighted. 相似文献
18.
Dr. Anna Loiudice Peter Lobaccaro Esmail A. Kamali Timothy Thao Brandon H. Huang Dr. Joel W. Ager Prof. Raffaella Buonsanti 《Angewandte Chemie (International ed. in English)》2016,55(19):5789-5792
Favoring the CO2 reduction reaction (CO2RR) over the hydrogen evolution reaction and controlling the selectivity towards multicarbon products are currently major scientific challenges in sustainable energy research. It is known that the morphology of the catalyst can modulate catalytic activity and selectivity, yet this remains a relatively underexplored area in electrochemical CO2 reduction. Here, we exploit the material tunability afforded by colloidal chemistry to establish unambiguous structure/property relations between Cu nanocrystals and their behavior as electrocatalysts for CO2 reduction. Our study reveals a non‐monotonic size‐dependence of the selectivity in cube‐shaped copper nanocrystals. Among 24 nm, 44 nm and 63 nm cubes tested, the cubes with 44 nm edge length exhibited the highest selectivity towards CO2RR (80 %) and faradaic efficiency for ethylene (41 %). Statistical analysis of the surface atom density suggests the key role played by edge sites in CO2RR. 相似文献
19.
Dr. Zedong Zhang Jiexin Zhu Dr. Shenghua Chen Prof. Wenming Sun Prof. Dingsheng Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(3):e202215136
Precise design and tuning of the micro-atomic structure of single atom catalysts (SACs) can help efficiently adapt complex catalytic systems. Herein, we inventively found that when the active center of the main group element gallium (Ga) is downsized to the atomic level, whose characteristic has significant differences from conventional bulk and rigid Ga catalysts. The Ga SACs with a P, S atomic coordination environment display specific flow properties, showing CO products with FE of ≈92 % at −0.3 V vs. RHE in electrochemical CO2 reduction (CO2RR). Theoretical simulations demonstrate that the adaptive dynamic transition of Ga optimizes the adsorption energy of the *COOH intermediate and renews the active sites in time, leading to excellent CO2RR selectivity and stability. This liquid single atom catalysts system with dynamic interfaces lays the foundation for future exploration of synthesis and catalysis. 相似文献
20.
Prof. Neng Li Dr. Xiao Wang Xuelian Lu Prof. Peng Zhang Prof. Wee-Jun Ong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(71):17900-17909
In this work, a series of non-noble metal single-atom catalysts of Mo2CS2-MXene for CO2 reduction were systematically investigated by well-defined density-functional-theory (DFT) calculations. It is found that nine types of transitional metal (TM) supported Mo2CS2 (TM-Mo2CS2) are very stable, while eight can effectively inhibit the competitive hydrogen evolution reaction (HER). After comprehensively comparing the changes of free energy for each pathway in CO2 reduction reaction (CO2RR), it is found that the products of TM-Mo2CS2 are not completely CH4. Furthermore, Cr-, Fe-, Co- and Ni-Mo2CS2 are found to render excellent CO2RR catalytic activity, and their limiting potentials are in the range of 0.245–0.304 V. In particular, Fe-Mo2CS2 with a nitrogenase-like structure has the lowest limiting potential and the highest electrocatalytic activity. Ab initio molecular dynamics (AIMD) simulations have also proven that these kinds of single-atom catalysts with robust performance could exist stably at room temperature. Therefore, these single TM atoms anchored on the surface of MXenes can be profiled as a promising catalyst for the electrochemical reduction of CO2. 相似文献