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Kinetic-boosted CO_(2) electroreduction to formate via synergistic electric-thermal field on hierarchical bismuth with amorphous layer
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作者 Bing Yang Junyi Zeng +4 位作者 Zhenlin Zhang Lin Meng Donglin Shi Liang Chen Youju Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期233-243,I0007,共12页
Electrocatalytic converting CO_(2) into chemical products has emerged as a promising approach to achieving carbon neutrality.Herein,we report a bismuth-based catalyst with high curvature terminal and amorphous layer w... Electrocatalytic converting CO_(2) into chemical products has emerged as a promising approach to achieving carbon neutrality.Herein,we report a bismuth-based catalyst with high curvature terminal and amorphous layer which fabricated via two-step electrodeposition achieves stable formate output in a wide voltage window of 600 mV.The Faraday efficiency(FE) of formate reached up to 99.4% at-0.8 V vs.RHE and it remained constant for more than 92 h at-15 mA cm^(-2).More intriguingly,FE formate of95.4% can be realized at a current density of industrial grade(-667.7 mA cm^(-2)) in flow cell.The special structure promoted CO_(2) adsorption and reduced its activation energy and enhanced the electric-thermal field and K^(+) enrichment which accelerated the reaction kinetics.In situ spectroscopy and theoretical calculation further confirmed that the introduction of amorphous structure is beneficial to adsorpting CO_(2)and stabling*OCHO intermediate.This work provides special insights to fabricate efficient electrocatalysts by means of structural and crystal engineering and makes efforts to realize the industrialization of bismuth-based catalysts. 展开更多
关键词 co_(2) electroreduction Hierarchical bismuth Amorphous layer Electric-thermal field Kinetic-boosting
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SCCO_(2)作用下不同含水性煤孔裂隙结构变化机制
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作者 张小东 靳沙沙 +2 位作者 张瑜 张硕 韩磊 《煤炭学报》 EI CAS CSCD 北大核心 2024年第7期3143-3153,共11页
深部煤层封存CO_(2)增产CH_(4)产出过程中,处于超临界状态的CO_(2)(SCCO_(2))与煤中矿物质发生反应,改变煤的孔隙性,进而影响煤层封存CO_(2)的效果和甲烷增产效果。为发现SCCO_(2)–H_(2)O–煤岩作用对煤中孔隙的影响特征,以焦煤为研究... 深部煤层封存CO_(2)增产CH_(4)产出过程中,处于超临界状态的CO_(2)(SCCO_(2))与煤中矿物质发生反应,改变煤的孔隙性,进而影响煤层封存CO_(2)的效果和甲烷增产效果。为发现SCCO_(2)–H_(2)O–煤岩作用对煤中孔隙的影响特征,以焦煤为研究对象,开展了不同含水条件下的超临界CO_(2)改造煤实验,基于矿物组成和孔隙性测定结果,对比煤中主要矿物质和不同尺度的孔裂隙变化的差异,探讨了不同含水状态下SCCO_(2)流体对孔裂隙性的作用机制。研究表明:①SCCO_(2)作用后,煤体表面粗糙、疏松,且由于矿物溶蚀使得一些裂隙得到贯通,微裂隙连通性增强。②SCCO_(2)流体对煤具有“扩孔”作用,表现为微、小孔含量下降,中、大孔占比升高,也即微、小孔隙向大孔隙的转化,且孔隙连通性改善;进一步发现,萃余煤吸附孔的分形维数稍微增加,粗糙度增大,而渗流孔的分形维数显著降低,复杂性和非均质性降低。③SCCO_(2)对煤中碳酸盐类矿物的溶解性最好,其次是黏土矿物,且随着含水率增加,萃余煤中的碳酸盐矿物占比先增加后减小。SCCO_(2)使干燥基态、饱和水态煤样中碳酸盐矿物显著溶解,有效改善了孔隙结构,且对饱和水态煤样作用效果更好。空气干燥基态煤样经SCCO_(2)作用后,新生成的白云石矿物聚集在孔喉中造成堵孔效应,缩小原有大孔隙尺寸,是引起不同含水性煤孔隙差异性变化的主要原因。 展开更多
关键词 焦煤 孔裂隙结构 含水性 超临界状态的co_(2) co_(2)封存
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CuAl-LDHs/CNTs优势组装及电催化CO_(2)还原制甲醇的研究
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作者 赵正一 王佳玮 +2 位作者 张娟 李嘉丞 吴旭 《功能材料》 CAS CSCD 北大核心 2024年第7期7022-7030,共9页
双碳背景下,电催化CO_(2)制甲醇等化合物有重要研究价值。为了提高CO_(2)的转化率和甲醇的选择性,本文借助兼具酸碱性的铜铝类水滑石(CuAl-LDHs)和具有优异导电性的碳纳米管材料(CNTs),协调构筑了LDHs/CNTs杂化物,实现了两种材料的优势... 双碳背景下,电催化CO_(2)制甲醇等化合物有重要研究价值。为了提高CO_(2)的转化率和甲醇的选择性,本文借助兼具酸碱性的铜铝类水滑石(CuAl-LDHs)和具有优异导电性的碳纳米管材料(CNTs),协调构筑了LDHs/CNTs杂化物,实现了两种材料的优势互补,使其制甲醇性能和导电性能双向提高。研究结果表明,相较于LDHs,杂化物中二者良好的分散性和丰富的弱碱位点更有利于CO_(2)分子在其表面大量吸附并快速扩散,同时具有高迁移率的晶格氧和高还原电位的一价铜物种在催化剂表面形成了氧化还原循环,显著降低了传质阻力和电子转移难度,使得CuAl-LDHs/5%CNTs在-0.6 V(针对可逆氢电极)下对甲醇拥有较高的选择性和电流密度,最高可达80.7%和-6.5 mA/cm 2,为开发在低电位高电流密度下具有高CO_(2)转化率的LDHs基电催化剂提供了重要参考。 展开更多
关键词 类水滑石 碳纳米管 甲醇 co_(2)电还原
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超临界CO_(2)板式扩散焊矩形微通道换热器扰流格栅结构优化研究
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作者 任燕 王沛东 +4 位作者 李洪 刘婧楠 武卫东 章立新 杨其国 《中国电机工程学报》 EI CSCD 北大核心 2024年第12期4850-4858,I0020,共10页
为提升超临界二氧化碳(supercritical carbon dioxide,S-CO_(2))布雷顿循环系统中印刷电路板式换热器(printed circuit heat exchanger,PCHE)的流动传热综合性能,该文通过数值模拟的方法,基于一种全蚀刻工艺的新型矩形截面PCHE,建立以... 为提升超临界二氧化碳(supercritical carbon dioxide,S-CO_(2))布雷顿循环系统中印刷电路板式换热器(printed circuit heat exchanger,PCHE)的流动传热综合性能,该文通过数值模拟的方法,基于一种全蚀刻工艺的新型矩形截面PCHE,建立以冷热通道换热单元为研究对象的数学物理模型。研究不同运行工况下,通道内扰流格栅间距对S-CO_(2)流动传热特性的影响机理和影响规律。结果表明:不同格栅间距的热通道内S-CO_(2)的流速均沿程逐渐减小,而冷通道内S-CO_(2)的流速反而沿程逐渐增大。冷热通道内的流动摩擦阻力系数(f)和努塞尔数(Nu)均随着格栅间距的增大而逐渐增大,但不同格栅间距的冷通道内的f和Nu均大于其对应的热通道内的f和Nu。当格栅间距为5.97 mm时,矩形截面通道具有相对最优的综合性能,可以在阻力损失较小的情况下实现强化换热。研究结果可为全蚀刻工艺矩形截面PCHE的性能提升和结构优化提供理论依据和数据支撑。 展开更多
关键词 超临界二氧化碳(S-co_(2)) 印刷电路板式换热器 矩形截面 格栅间距 综合传热增强因子
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电解铝CO_(2)资源化利用的隔膜电解池的设计
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作者 宋文康 沈风霞 +3 位作者 吴帅 华雅鑫 张金忠 施锦 《化学研究》 CAS 2024年第2期140-146,共7页
将工业废气中的CO_(2)转化为高值化学品,创造经济效益,是CO_(2)高排放行业迫切需要解决的重大现实问题。然而,由于缺乏工业适用的电化学反应装置,研究工作一直未取得实质性突破。针对上述问题,提出了一种新型隔膜电解池,可以在阴极上将C... 将工业废气中的CO_(2)转化为高值化学品,创造经济效益,是CO_(2)高排放行业迫切需要解决的重大现实问题。然而,由于缺乏工业适用的电化学反应装置,研究工作一直未取得实质性突破。针对上述问题,提出了一种新型隔膜电解池,可以在阴极上将CO_(2)电还原为CO,在阳极上将HCl氧化成Cl_2,所得CO、Cl_2用于合成光气。通过这种方法,不仅可以实现CO_(2)减排,还可以解决含HCl工业废气综合利用问题。为了提高电解CO_(2)制CO的效率,采用无氰电镀法制备了三维流通型Ag/Cu多孔修饰电极,通过提高电极比表面积,增加活性位点,将阴极电流密度提高至46.3 mA/cm^(2),生成CO的法拉第效率稳定在92.52%。本项研究在电能储存和CO_(2)减排领域具有重要理论研究价值和工程应用前景。 展开更多
关键词 隔膜电解池 co_(2)电还原 含HCl废气循环利用 多孔修饰电极
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连续翻压黑麦草对豫中植烟土壤剖面CO_(2)日排放变化的影响
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作者 王晶 杨佳豪 +6 位作者 陈雨露 姚鹏伟 鲁琪飞 陈树鸿 陈炬廷 位辉琴 叶协锋 《中国烟草学报》 CAS CSCD 北大核心 2024年第2期42-51,共10页
【目的】探究豫中烟区翻压黑麦草对烤烟生长过程中土壤呼吸速率、土壤剖面二氧化碳(CO_(2))日排放变化的影响及其与环境因子的关系,明确CO_(2)采集最佳观测时间。【方法】2021年在河南农业大学郑州科教园区设置2个处理(依托于长期定位试... 【目的】探究豫中烟区翻压黑麦草对烤烟生长过程中土壤呼吸速率、土壤剖面二氧化碳(CO_(2))日排放变化的影响及其与环境因子的关系,明确CO_(2)采集最佳观测时间。【方法】2021年在河南农业大学郑州科教园区设置2个处理(依托于长期定位试验),施氮磷钾肥(NPK)、氮磷钾+种植并翻压黑麦草(NPKG),烟苗移栽后每隔30d测定烟田CO_(2)排放日变化过程。【结果】(1)0~10 cm地温与土壤呼吸速率均表现为昼高夜低的单峰或双峰形态。NPKG处理土壤呼吸速率显著高于NPK处理,9:00和21:00矫正系数最接近1且与日平均排放无显著差异。(2)随着土层加深,CO_(2)浓度升高,CO_(2)扩散通量降低,同层土壤NPKG处理CO_(2)浓度和扩散通量高于NPK处理。0、5、10和20 cm土层CO_(2)浓度和0~20 cm土层扩散通量有明显日变化特征,90 d时CO_(2)浓度较60 d降低。(3)土壤呼吸速率与0~20 cm土层CO_(2)扩散通量呈显著或极显著正相关关系。【结论】黑麦草翻压加快土壤呼吸速率、提高了各土层CO_(2)浓度和CO_(2)扩散通量。9:00左右和21:00左右为最佳取样时间段,5 cm和10 cm土层CO_(2)浓度和5~10 cm土层扩散通量与土壤呼吸速率日变化特征相似,3个取样日CO_(2)浓度以60 d最高,30 d次之。可根据土壤CO_(2)浓度预测土壤呼吸速率。 展开更多
关键词 日变化 二氧化碳(co_(2)) 土壤呼吸 土壤剖面 烤烟
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Plasma induced grain boundaries to boost electrochemical reduction of CO_(2)to formate
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作者 Guan Wang Shengtao Zhong +9 位作者 Xiaoqian Xiong Jing Li Fangyuan Wang Li Huo Daoxiong Wu Xingqi Han Zhitong Wang Qi Chen Xinlong Tian Peilin Deng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期636-643,I0014,共9页
Bismuth-based catalysts are highly promising for the electrochemical carbon dioxide reduction reaction(eCO_(2)RR)to formate product.However,achieving high activity and selectivity towards formate and ensuring long-ter... Bismuth-based catalysts are highly promising for the electrochemical carbon dioxide reduction reaction(eCO_(2)RR)to formate product.However,achieving high activity and selectivity towards formate and ensuring long-term stability remains challenging.This work reports the oxygen plasma inducing strategy to construct the abundant grain boundaries of Bi/BiO_x on ultrathin two-dimensional Bi nanosheets.The oxygen plasma-treated Bi nanosheet(OP-Bi)exhibits over 90%Faradaic efficiency(FE)for formate at a wide potential range from-0.5 to-1.1 V,and maintains a great stability catalytic performance without significant decay over 30 h in flow cell.Moreover,membrane electrode assembly(MEA)device with OPBi as catalyst sustains the robust current density of 100 mA cm^(-2)over 50 h,maintaining a formate FE above 90%.In addition,rechargeable Zn-CO_(2)battery presents the peak power density of1.22 mW cm^(-2)with OP-Bi as bifunctional catalyst.The mechanism experiments demonstrate that the high-density grain boundaries of OP-Bi provide more exposed active sites,faster electron transfer capacity,and the stronger intrinsic activity of Bi atoms.In situ spectroscopy and theo retical calculations further elucidate that the unsaturated Bi coordination atoms between the grain boundaries can effectively activate CO_(2)molecules through elongating the C-O bond,and reducing the formation energy barrier of the key intermediate(^(*)OCOH),thereby enhancing the catalytic performance of eCO_(2)RR to formate product. 展开更多
关键词 co_(2)electroreduction Bi nanosheet Grain boundary Unsaturation Bi atoms MEA device
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Porous metal oxides in the role of electrochemical CO_(2) reduction reaction
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作者 Ziqi Zhang Jinyun Xu +9 位作者 Yu Zhang Liping Zhao Ming Li Guoqiang Zhong Di Zhao Minjing Li Xudong Hu Wenju Zhu Chunming Zheng Xiaohong Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期373-398,I0009,共27页
The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous me... The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous metal oxide materials in the electrocatalytic reduction of CO_(2)(CO_(2)RR).The focus is on the development of robust and selective catalysts,particularly metal and metal-oxide-based materials.Porous metal oxides offer high surface area,enhancing the accessibility to active sites and improving reaction kinetics.The tunability of these materials allows for tailored catalytic behavior,targeting optimized reaction mechanisms for CO_(2)RR.The work also discusses the various synthesis strategies and identifies key structural and compositional features,addressing challenges like high overpotential,poor selectivity,and low stability.Based on these insights,we suggest avenues for future research on porous metal oxide materials for electrochemical CO_(2) reduction. 展开更多
关键词 co_(2)reduction Carbon dioxide TRANSFORMATION Porous metal oxides ELECTROCATALYSIS
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Tackling the proton limit under industrial electrochemical CO_(2)reduction by a local proton shuttle
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作者 Tianye Shao Kang Yang +4 位作者 Sheng Chen Min Zheng Ying Zhang Qiang Li Jingjing Duan 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期233-243,共11页
Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In th... Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In this work,an ion‐polymer‐modified gas‐diffusion electrode is used to tackle this proton limit.It is found that gas diffusion electrode‐Nafion shows an impressive performance of 75.2%Faradaic efficiency in multicarbon products at an industrial current density of 1.16 A/cm^(2).Significantly,in‐depth electrochemical characterizations combined with in situ Raman have been used to determine the full workflow of protons,and it is found that HCO_(3)^(−)acts as a proton pool near the reaction environment,and HCO_(3)^(−)and H_(3)O^(+)are local proton donors that interact with the proton shuttle−SO_(3)^(−)from Nafion.With rich proton hopping sites that decrease the activation energy,a“Grotthuss”mechanism for proton transport in the above system has been identified rather than the“Vehicle”mechanism with a higher energy barrier.Therefore,this work could be very useful in terms of the achievement of industrial CO_(2)reduction fundamentally and practically. 展开更多
关键词 industrial co_(2)electroreduction proton donor proton pool proton shuttle proton transport mechanism
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Electrocatalytic CO_(2) reduction to C_(2)H_(4): From lab to fab
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作者 Zeyu Guo Fabao Yang +10 位作者 Xiaotong Li Huiwen Zhu Hainam Do Kam Loon Fow Jonathan D.Hirst Tao Wu Qiulin Ye Yaqi Peng Hao Bin Wu Angjian Wu Mengxia Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期540-564,I0012,共26页
The global concerns of energy crisis and climate change,primarily caused by carbon dioxide(CO_(2)),are of utmost importance.Recently,the electrocatalytic CO_(2) reduction reaction(CO_(2)RR) to high value-added multi-c... The global concerns of energy crisis and climate change,primarily caused by carbon dioxide(CO_(2)),are of utmost importance.Recently,the electrocatalytic CO_(2) reduction reaction(CO_(2)RR) to high value-added multi-carbon(C_(2+)) products driven by renewable electricity has emerged as a highly promising solution to alleviate energy shortages and achieve carbon neutrality.Among these C_(2+) products,ethylene(C_(2)H_(4))holds particular importance in the petrochemical industry.Accordingly,this review aims to establish a connection between the fundamentals of electrocatalytic CO_(2) reduction reaction to ethylene(CO_(2)RRto-C_(2)H_(4)) in laboratory-scale research(lab) and its potential applications in industrial-level fabrication(fab).The review begins by summarizing the fundamental aspects,including the design strategies of high-performance Cu-based electrocatalysts and advanced electrolyzer devices.Subsequently,innovative and value-added techniques are presented to address the inherent challenges encountered during the implementations of CO_(2)RR-to-C_(2)H_(4) in industrial scenarios.Additionally,case studies of the technoeconomic analysis of the CO_(2)RR-to-C_(2)H_(4) process are discussed,taking into factors such as costeffectiveness,scalability,and market potential.The review concludes by outlining the perspectives and challenges associated with scaling up the CO_(2)RR-to-C_(2)H_(4) process.The insights presented in this review are expected to make a valuable contribution in advancing the CO_(2)RR-to-C_(2)H_(4) process from lab to fab. 展开更多
关键词 co_(2) electroreduction reaction ETHYLENE Gas diffusion electrode Machine learning Density functional theory Techno-economic analysis
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In-situ constructing Cu_(1)Bi_(1)bimetallic catalyst to promote the electroreduction of CO_(2)to formate by synergistic electronic and geometric effects 被引量:2
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作者 Houan Ren Xiaoyu Wang +5 位作者 Xiaomei Zhou Teng Wang Yuping Liu Cai Wang Qingxin Guan Wei Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期263-271,共9页
Electrochemical CO_(2)reduction to formate is a potential approach to achieving global carbon neutrality.Here,Cu1Bi1bimetallic catalyst was prepared by a co-precipitation method.It has a ginger like composite structur... Electrochemical CO_(2)reduction to formate is a potential approach to achieving global carbon neutrality.Here,Cu1Bi1bimetallic catalyst was prepared by a co-precipitation method.It has a ginger like composite structure(CuO/CuBi_(2)O_(4))and exhibited a high formate faradaic efficiency of 98.07%at–0.98 V and a large current density of–56.12 mA.cm^(-2)at–1.28 V,which is twice as high as Bi2O3catalyst.Especially,high selectivity(FE^(–)_(HCOO)>85%)is maintained over a wide potential window of 500 mV.In-situ Raman measurements and structure characterization revealed that the reduced Cu1Bi1bimetallic catalyst possesses abundant Cu-Bi interfaces and residual Bi-O structures.The abundant Cu-Bi interface structures on the catalyst surface can provide abundant active sites for CO_(2)RR,while the Bi-O structures may stabilize the CO_(2)^(*–)intermediate.The synergistic effect of abundant Cu-Bi interfaces and Bi-O species promotes the efficient synthesis of formate by following the OCHO^(*)pathway. 展开更多
关键词 co_(2)electroreduction Bimetallic catalyst FORMATE Cu-Bi interfaces Bi-O structure
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Cu/TiO_(2) Photocatalysts for CO_(2) Reduction: Structure and Evolution of the Cocatalyst Active Form
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作者 Andrey A.Saraev Anna Yu.Kurenkova +3 位作者 Denis D.Mishchenko Alexandr L.Trigub Evgeniy Yu.Gerasimov Ekaterina A.Kozlova 《Transactions of Tianjin University》 EI CAS 2024年第2期140-151,共12页
Extensive work on a Cu-modified TiO_(2) photocatalyst for CO_(2) reduction under visible light irradiation was conducted. The structure of the copper cocatalyst was established using UV-vis diff use refl ectance spect... Extensive work on a Cu-modified TiO_(2) photocatalyst for CO_(2) reduction under visible light irradiation was conducted. The structure of the copper cocatalyst was established using UV-vis diff use refl ectance spectroscopy, high-resolution transmis- sion electron microscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. It was found that copper exists in different states (Cu 0 , Cu^(+) , and Cu^(2+) ), the content of which depends on the TiO_(2) calcination temperature and copper loading. The optimum composition of the cocatalyst has a photocatalyst based on TiO_(2) calcined at 700℃ and modified with 5 wt% copper, the activity of which is 22 μmol/(h·g cat ) (409 nm). Analysis of the photocatalysts after the photocatalytic reaction disclosed that the copper metal on the surface of the calcined TiO_(2) was gradually converted into Cu_(2) O during the photocatalytic reaction. Meanwhile, the metallic copper on the surface of the noncalcined TiO_(2) did not undergo any trans- formation during the reaction. 展开更多
关键词 PHOTOCATALYSIS Photocatalytic co_(2)conversion Visible light Titanium dioxide copper copper oxides Methane formation Photocatalyst transformation
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充分稳定和暴露的铜基异质结实现CO_(2)高效电还原制乙醇
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作者 蒋兴星 赵雨昕 +5 位作者 孔艳 孙建桔 冯上照 胡琪 杨恒攀 何传新 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第3期216-225,共10页
二氧化碳(CO_(2))虽然被视为破坏生态环境的温室气体,但也是储量最丰富的碳资源,对其进行转化和利用将对社会环境和能源结构产生深远影响.电化学还原CO_(2)(CO_(2)RR)不仅转化效率高,而且成本较低,有望实现规模化生产.在众多催化剂中,... 二氧化碳(CO_(2))虽然被视为破坏生态环境的温室气体,但也是储量最丰富的碳资源,对其进行转化和利用将对社会环境和能源结构产生深远影响.电化学还原CO_(2)(CO_(2)RR)不仅转化效率高,而且成本较低,有望实现规模化生产.在众多催化剂中,廉价易得的铜基催化剂被认为是电化学催化还原CO_(2)生成高附加值产物的理想催化剂之一,其中铜氧化物的存在是CO_(2)RR生成高附加值产物的关键.然而,CO_(2)RR过程是在负电位下进行的,当施加电位低于‒0.1 VRHE时,铜氧化物很容易被还原为金属态铜.因此,催化剂稳定氧化态铜的能力在保持连续、高效和稳定的CO_(2)RR产多碳产物性能中至关重要.本文将简单的O_(2)等离子体处理技术与静电纺丝技术相结合,合成了多孔碳纳米纤维负载的Cu/Cu_(x)O异质结催化剂,并考察了其催化CO_(2)RR的性能.在静电纺丝过程中,Cu-ZIF-8前驱体的加入使得热处理后的原丝纤维中形成了丰富的网络贯穿多孔结构,该结构有效地实现了铜纳米颗粒的均匀分散;随后,通过O_(2)等离子体处理技术,在碳纳米纤维中构建了大量的开放介孔,为CO_(2)的吸附和反应提供了有利环境,并使Cu/Cu_(x)O异质结位点暴露于反应界面.电化学性能测试结果表明,在400 mA cm^(‒2)电流密度下,独特的Cu/Cu_(x)O异质结活性位点电催化还原CO_(2)生成乙醇的法拉第效率可达70.7%,该性能优于未经O_(2)等离子体处理的多孔铜纳米纤维.此外,高暴露的Cu/Cu_(x)O异质结活性位点显著地增加实际参与反应的活性位点数量,经计算Cu/Cu_(x)O异质结CO_(2)RR产乙醇的质量活性高达8.4 A mg^(‒1),是目前报道生产乙醇的较高质量活性.多孔碳纳米纤维衬底不仅具有协同电子输运能力,而且在CO_(2)RR测试中施加的负电压有助于维持Cu/Cu_(x)O异质结构的稳定性,使其在高电流密度下能够保持长时间的催化稳定性.此外,本文利用原位拉曼光谱和红外光谱、有限元模拟及密度泛函理论计算等方法深入研究了Cu/Cu_(x)O异质结的催化机理.原位拉曼光谱和红外光谱表征结果证实了在CO_(2)RR过程中Cu_(x)O的动态稳定状态以及关键信号*CO和C‒C键的存在;理论计算表明,Cu/Cu_(x)O异质结的存在促进了关键中间体*CO的溢流,降低了C‒C耦合过程的反应能垒,从而提高了还原产物乙醇的产率.综上,本文成功地在多孔铜纳米纤维中引入氧化物物种,并优化了纤维孔结构.其表现出了较好的电催化还原CO_(2)性能,可高选择性生成乙醇,其独特的多孔碳纤维结构充分暴露了活性位点,实现了较高的质量活性.本文所采用的催化剂组分和微观结构的调控策略为提升电催化中催化剂稳定性和催化活性提供了有益的借鉴. 展开更多
关键词 二氧化碳电还原 Cu/Cu_(x)O异质结 开口孔结构 质量活性 乙醇
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Synergistic regulation of hydrophobicity and basicity for copper hydroxide-derived copper to promote the CO_(2)electroreduction reaction 被引量:2
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作者 Limin Zhou Chenghang Li +8 位作者 Jing-Jing Lv Wei Wang Shaojun Zhu Jun Li Yifei Yuan Zheng-Jun Wang Qingcheng Zhang Huile Jin Shun Wang 《Carbon Energy》 SCIE CSCD 2023年第6期72-81,共10页
A simple method was proposed to activate alkaline Cu(OH)_(2)with an acidic ionomer,Nafion,to regulate its surface microenvironment,including hydrophobicity and local basicity.In particular,the direct complete neutrali... A simple method was proposed to activate alkaline Cu(OH)_(2)with an acidic ionomer,Nafion,to regulate its surface microenvironment,including hydrophobicity and local basicity.In particular,the direct complete neutralization reaction between Cu(OH)_(2)and Nafion in aqueous solution induces the exposing of vast anions which can exclude the in-situ-formed hydroxides and raise the local basicity.Remarkably,the optimal Nafionactivated Cu(OH)_(2)-derived Cu can efficiently suppress the hydrogen evolution reaction(HER)and improve the selectivity for multi-carbon products in the CO_(2)electroreduction reaction(eCO_(2)RR).The H2 Faradaic efficiency(FE)decreased to 11%at a current density of 300 mA/cm2(−0.76 V vs.RHE)in a flow cell,while the bare one with H2 had an FE of 40%.The total eCO_(2)RR FE reaches as high as 83%,along with an evidently increased C2H4 FE of 44%as compared with the bare one(24%),and good stability(8000 s),surpassing that of most of the reported Cu(OH)_(2)-derived Cu.The experimental and theoretical results both show that the strong hydrophobicity and high local basicity jointly boosted the eCO_(2)RR as acquired by felicitously introducing ionomer on the Cu(OH)_(2)-derived Cu surface. 展开更多
关键词 co_(2)electroreduction reaction Cu(OH)_(2)@Nafion flow cell IONOMERS multi-carbon products
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A hierarchically structured tin-cobalt composite with an enhanced electronic effect for high-performance CO_(2) electroreduction in a wide potential range 被引量:1
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作者 Xingxing Jiang Xuan Li +5 位作者 Yan Kong Chen Deng Xiaojie Li Qi Hu Hengpan Yang Chuanxin He 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期462-469,I0012,共9页
Earth-abundant and nontoxic Sn-based materials have been regarded as promising catalysts for the electrochemical conversion of CO_(2)to C1 products,e.g.,CO and formate.However,it is still difficult for Snbased materia... Earth-abundant and nontoxic Sn-based materials have been regarded as promising catalysts for the electrochemical conversion of CO_(2)to C1 products,e.g.,CO and formate.However,it is still difficult for Snbased materials to obtain satisfactory performance at low-to-moderate overpotentials.Herein,a simple and facile electrospinning technique is utilized to prepare a composite of a bimetallic Sn-Co oxide/carbon matrix with a hollow nanotube structure(Sn Co-HNT).Sn Co-HNT can maintain>90%faradaic efficiencies for C1 products within a wide potential range from-0.6 VRHE to-1.2 VRHE,and a highest 94.1%selectivity towards CO in an H-type cell.Moreover,a 91.2%faradaic efficiency with a 241.3 m A cm^(-2)partial current density for C1 products could be achieved using a flow cell.According to theoretical calculations,the fusing of Sn/Co oxides on the carbon matrix accelerates electron transfer at the atomic level,causing electron deficiency of Sn centers and reversible variation between Co^(2+)and Co^(3+)centers.The synergistic effect of the Sn/Co composition improves the electron affinity of the catalyst surface,which is conducive to the adsorption and stabilization of key intermediates and eventually increases the catalytic activity in CO_(2)electroreduction.This study could provide a new strategy for the construction of oxide-derived catalysts for CO_(2)electroreduction. 展开更多
关键词 Hierarchic structure Tin-cobalt bimetallic oxide Electronic effect co_(2)electroreduction Wide potential range
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Switching CO_(2) Electroreduction Selectivity Between C_(1) and C_(2) Hydrocarbons on Cu Gas-Diffusion Electrodes 被引量:1
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作者 Jianfang Zhang Zhengyuan Li +6 位作者 Rui Cai Tianyu Zhang Shize Yang Lu Ma Yan Wang Yucheng Wu Jingjie Wu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期17-25,共9页
Regulating the selectivity toward a target hydrocarbon product is still the focus of CO_(2)electroreduction.Here,we discover that the original surface Cu species in Cu gas-diffusion electrodes plays a more important r... Regulating the selectivity toward a target hydrocarbon product is still the focus of CO_(2)electroreduction.Here,we discover that the original surface Cu species in Cu gas-diffusion electrodes plays a more important role than the surface roughness,local pH,and facet in governing the selectivity toward C_(1)or C_(2)hydrocarbons.The selectivity toward C_(2)H_(4) progressively increases,while CH_(4) decreases steadily upon lowering the Cu oxidation species fraction.At a relatively low electrodeposition voltage of 1.5 V,the Cu gas-diffusion electrode with the highest Cu^(δ+)/Cu^(0)ratio favors the pathways of∗CO hydrogenation to form CH_(4) with maximum Faradaic efficiency of 65.4%and partial current density of 228 mA cm^(−2)at−0.83 V vs RHE.At 2.0 V,the Cu gas-diffusion electrode with the lowest Cu^(δ+)/Cu^(0)ratio prefers C-C coupling to form C_(2)+products with Faradaic efficiency topping 80.1%at−0.75 V vs RHE,where the Faradaic efficiency of C_(2)H_(4) accounts for 46.4%and the partial current density of C_(2)H_(4) achieves 279 mA cm^(−2).This work demonstrates that the selectivity from CH_(4) to C_(2)H_(4) is switchable by tuning surface Cu species composition of Cu gas-diffusion electrodes. 展开更多
关键词 C_(2)H_(4) CH_(4) co_(2)electroreduction ELECTRODEPOSITION switchable selectivity
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高浓度CO_(2)短时处理对西梅采后贮藏品质及抗氧化代谢的影响
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作者 刘志旭 朱璇 +4 位作者 赵亚婷 张昱 石慧敏 栾若林 刘嘉宝 《食品工业科技》 CAS 北大核心 2024年第12期311-318,共8页
为明确高浓度二氧化碳(carbon dioxide,CO_(2))短时处理对西梅采后贮藏品质及抗氧化代谢的影响,以新疆‘法兰西’西梅为试材,分别采用45%、60%、75%的CO_(2)熏蒸西梅果实3 h,于1.0±0.5℃条件下贮藏49 d,定期测定西梅果实硬度、色... 为明确高浓度二氧化碳(carbon dioxide,CO_(2))短时处理对西梅采后贮藏品质及抗氧化代谢的影响,以新疆‘法兰西’西梅为试材,分别采用45%、60%、75%的CO_(2)熏蒸西梅果实3 h,于1.0±0.5℃条件下贮藏49 d,定期测定西梅果实硬度、色泽、可溶性固形物含量、可滴定酸含量及抗氧化代谢相关指标。结果表明:高浓度CO_(2)短时处理可有效维持西梅果实硬度、色泽、可溶性固形物及可滴定酸含量水平,其中60%CO_(2)处理对西梅果实品质维持效果最佳。贮藏结束时,60%CO_(2)处理组西梅果实超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)、过氧化物酶(peroxidase,POD)、谷胱甘肽还原酶(glutathione reductase,GR)、抗坏血酸过氧化物酶(ascorbate peroxidase,APX)活性分别比对照组高5.71%、59.95%、27.40%、29.18%和45.00%(P<0.05),抗坏血酸(ascorbic acid,AsA)与谷胱甘肽(glutathione,GSH)含量是对照组的1.42倍和1.23倍,提高了西梅果实抗氧化酶活性,有效维持了AsA与GSH含量,降低了超氧阴离子(superoxide anion,O_(2)^(-)·)产生速率,延缓了过氧化氢(hydrogen peroxide,H_(2)O_(2))含量、丙二醛(malondialdehyde,MDA)含量的积累和细胞膜透性的上升。说明高浓度CO_(2)短时处理可增强西梅果实贮藏期间的抗氧化代谢,保持果实贮藏品质。 展开更多
关键词 西梅果实 二氧化碳(co_(2)) 采后保鲜 抗氧化代谢 贮藏品质
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碳达峰碳中和背景下电力电缆供应链的CO_(2)排放量控制方法研究
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作者 李俊颖 胡永焕 +2 位作者 董力 徐弘道 张行健 《环境科学与管理》 CAS 2024年第4期28-32,共5页
针对供应链CO_(2)排放量控制基于无损电力网络、忽略电力线路损耗造成CO_(2)排放的问题,提出碳达峰碳中和背景下电力电缆供应链的CO_(2)排放量控制方法。基于电力潮流分析理论引入CO_(2)排放流概念,并计算CO_(2)排放强度,在节点、支路... 针对供应链CO_(2)排放量控制基于无损电力网络、忽略电力线路损耗造成CO_(2)排放的问题,提出碳达峰碳中和背景下电力电缆供应链的CO_(2)排放量控制方法。基于电力潮流分析理论引入CO_(2)排放流概念,并计算CO_(2)排放强度,在节点、支路、支路有功损耗和负荷方面分析CO_(2)排放流分布情况,通过潮流溯源法对CO_(2)排放流溯源分析,将发电侧CO_(2)排放转移至用户侧,结合CO_(2)排放阈值,实现电力电缆供应链CO_(2)减排控制。实验结果表明,所提方法的回归相关系数达到了0.9824,均方误差仅为0.093,与文献方法相比,该方法的误差更小、回归相关系数更高。 展开更多
关键词 碳达峰碳中和 电力电缆供应链 co_(2) 碳排放流 潮流溯源法
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Amorphous Sn(HPO_(4))_(2)-derived phosphorus-modified Sn/SnO_(x) core/shell catalyst for efficient CO_(2) electroreduction to formate
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作者 Chunfeng Cheng Tianfu Liu +7 位作者 Yi Wang Pengfei Wei Jiaqi Sang Jiaqi Shao Yanpeng Song Yipeng Zang Dunfeng Gao Guoxiong Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期125-131,I0005,共8页
Simultaneously achieving high activity,selectivity and stability for electrochemical CO_(2)reduction reaction(CO_(2)RR)remains great challenges.Herein,a phosphorus-modified Sn/Sn Oxcore/shell(P-Sn/SnO_x)catalyst,deriv... Simultaneously achieving high activity,selectivity and stability for electrochemical CO_(2)reduction reaction(CO_(2)RR)remains great challenges.Herein,a phosphorus-modified Sn/Sn Oxcore/shell(P-Sn/SnO_x)catalyst,derived from in situ electrochemical reduction of an amorphous Sn(HPO_(4))_(2) pre-catalyst,exhibits high CO_(2)RR performance.The total Faradaic efficiency(FE)of C_(1) products is close to 100%in a broad potential range from-0.49 to-1.02 V vs.reversible hydrogen electrode,and a total current density of 315.0 m A cm^(-2)is achieved.Moreover,the P-Sn/SnO_(x) catalyst maintains a formate FE of~90%for 120 h.Density functional theory calculations suggest that the phosphorus-modified Sn/SnO_(x) core/shell structure effectively facilitates formate production by enhancing CO_(2)adsorption and improving free energy profile of formate formation. 展开更多
关键词 co_(2)electroreduction Structural evolution Reaction intermediate Phosphorus modification Stability
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Advances and challenges of electrolyzers for large-scale CO_(2) electroreduction
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作者 Lei Yuan Shaojuan Zeng +2 位作者 Xiangping Zhang Xiaoyan Ji Suojiang Zhang 《Materials Reports(Energy)》 2023年第1期1-18,I0002,共19页
CO_(2) electroreduction(CO_(2) ER)to high value-added chemicals is considered as a promising technology to achieve sustainable carbon neutralization.By virtue of the progressive research in recent years aiming at desi... CO_(2) electroreduction(CO_(2) ER)to high value-added chemicals is considered as a promising technology to achieve sustainable carbon neutralization.By virtue of the progressive research in recent years aiming at design and understanding of catalytic materials and electrolyte systems,the CO_(2) ER performance(such as current density,selectivity,stability,CO_(2) conversion,etc.)has been continually increased.Unfortunately,there has been relatively little attention paid to the large-scale CO 2 electrolyzers,which stand just as one obstacle,alongside series-parallel integration,challenging the practical application of this infant technology.In this review,the latest progress on the structures of low-temperature CO_(2) electrolyzers and scale-up studies was systematically overviewed.The influence of the CO_(2) electrolyzer configurations,such as the flow channel design,gas diffusion electrode(GDE)and ion exchange membrane(IEM),on the CO_(2) ER performance was further discussed.The review could provide inspiration for the design of large-scale CO_(2) electrolyzers so as to accelerate the industrial application of CO_(2) ER technology. 展开更多
关键词 co_(2) electroreduction LARGE-SCALE co_(2) electrolyzer Flow channel Gas diffusion electrode Ion exchange membrane
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