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钙钛矿型铁酸盐氧化还原催化剂的晶格氧释放动力学研究
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作者 聂红 《物理化学学报》 SCIE CAS CSCD 北大核心 2022年第8期4-5,共2页
绿色化工技术是实现化工行业可持续发展的关键^(1)。作为一种先进高效的低碳能源转化技术,化学链工艺在节能和减排等方面具有诸多优势^(2)。在化学链工艺中,氧化还原催化剂作为氧载体,实现不同反应器之间的晶格氧和热量传递。载氧体的... 绿色化工技术是实现化工行业可持续发展的关键^(1)。作为一种先进高效的低碳能源转化技术,化学链工艺在节能和减排等方面具有诸多优势^(2)。在化学链工艺中,氧化还原催化剂作为氧载体,实现不同反应器之间的晶格氧和热量传递。载氧体的晶格氧释放动力学是决定其反应性能的关键因素^(3)。ABO_(3)钙钛矿型复合金属氧化物由于其优良的结构循环稳定性和氧离子迁移能力,是一类具有潜在应用价值的催化材料,被广泛研究用于化学链、H_(2)O/CO_(2)热裂解和固体燃料电池等领域^(4)。 展开更多
关键词 氧化还原催化剂 固体燃料电池 释放动力学 复合金属氧化 化学链 钙钛矿型 铁酸盐 绿色化工技术
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美国北卡罗莱纳州立大学开发新型乙苯氧化脱氢制苯乙烯催化剂
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作者 《石油炼制与化工》 CAS CSCD 北大核心 2021年第8期121-121,共1页
美国北卡罗莱纳州立大学的研究团队开发一种新型氧化还原催化剂,其构成以铁酸钾为表面外壳,钙锰氧化物为核。该催化剂可以催化乙苯氧化脱氢生成苯乙烯,还能为反应提供氧,同时产生水;用空气吹扫该催化剂时可提高其氧化能力。此过程可提... 美国北卡罗莱纳州立大学的研究团队开发一种新型氧化还原催化剂,其构成以铁酸钾为表面外壳,钙锰氧化物为核。该催化剂可以催化乙苯氧化脱氢生成苯乙烯,还能为反应提供氧,同时产生水;用空气吹扫该催化剂时可提高其氧化能力。此过程可提高苯乙烯产率,同时减少能源消耗和CO_(2)排放。该研究成果发表于《自然通讯》杂志。 展开更多
关键词 氧化还原催化剂 团队开发 氧化 空气吹扫 乙苯氧化脱氢 苯乙烯 乙烯产率 氧化能力
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WO_x催化剂上正庚烷的临氢异构化反应 被引量:4
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作者 汪颖军 刘进祥 +2 位作者 靳丽丽 张志秋 刘丽莹 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2007年第2期74-78,共5页
采用连续流动固定床反应器考察了WOx催化剂上正庚烷加氢异构化反应性能。详细讨论了还原条件和反应条件对催化性能的影响。采用XRD和BET方法表征了催化剂的物化性质。结果表明,在WOx催化剂上,正庚烷转化率达到20.8%时,其异构化选择性仍... 采用连续流动固定床反应器考察了WOx催化剂上正庚烷加氢异构化反应性能。详细讨论了还原条件和反应条件对催化性能的影响。采用XRD和BET方法表征了催化剂的物化性质。结果表明,在WOx催化剂上,正庚烷转化率达到20.8%时,其异构化选择性仍然达到86.4%。推测催化剂的活性相为WO2和W3O,催化剂具有中孔结构。 展开更多
关键词 还原氧化催化剂 正庚烷 加氢异构化 活性位 中孔
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美国北卡罗莱纳州立大学开发新型催化剂更高效、环保地生产乙烯
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作者 张伟清(译) 《石油炼制与化工》 CAS CSCD 北大核心 2020年第10期22-22,共1页
由美国北卡罗莱纳州立大学领导的研究小组设计了一种可以更有效地将乙烷转化为乙烯的新型催化剂。该催化剂用于乙烷转化制乙烯工艺中,可以大幅降低乙烯生产成本,相关的二氧化碳排放量将削减87%。据该项目的主要参与者Gao Yunfei介绍,其... 由美国北卡罗莱纳州立大学领导的研究小组设计了一种可以更有效地将乙烷转化为乙烯的新型催化剂。该催化剂用于乙烷转化制乙烯工艺中,可以大幅降低乙烯生产成本,相关的二氧化碳排放量将削减87%。据该项目的主要参与者Gao Yunfei介绍,其所在实验室以前提出了一种将乙烷转化为乙烯的技术,这种新型氧化还原催化剂使该技术在降低温室气体排放的同时,更节能,且成本更低。 展开更多
关键词 乙烯生产 转化制 新型催化剂 氧化还原催化剂 氧化碳排放量 乙烷 温室气体排放 主要参与者
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机器学习在固体氧化物燃料电池、锂电池、CO_(2)电还原催化剂中的研究进展 被引量:2
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作者 许建兵 李翰实 +2 位作者 谭济民 韩敏芳 陈迪 《硅酸盐学报》 EI CAS CSCD 北大核心 2022年第11期3021-3039,共19页
随着清洁能源系统的推广应用,锂离子电池、固体氧化物燃料电池作为清洁能源器件受到广泛的关注。然而,作为复杂的电力动力系统,电池的商用化一直面临长时间、多维度、高精度的性能预测需求,一些新型的电池性能预测方法仍处于起步探索阶... 随着清洁能源系统的推广应用,锂离子电池、固体氧化物燃料电池作为清洁能源器件受到广泛的关注。然而,作为复杂的电力动力系统,电池的商用化一直面临长时间、多维度、高精度的性能预测需求,一些新型的电池性能预测方法仍处于起步探索阶段。近年来,随着人工智能的普及与推广,机器学习这项基于传统人工神经网络的技术被国内外研究者所重视。机器学习等数据科学的最新进展为科学和工程界提供了灵活而快速的预测框架,在材料研发等方面显示出巨大的应用前景。本工作总结了采用机器学习方法用于固态氧化物燃料电池、锂电池、CO_(2)电化学还原催化剂的最新进展,并对未来的发展方向提出了若干建议。 展开更多
关键词 数据科学 机器学习 绿色能源 固态氧化物燃料电池 锂电池 氧化碳电化学还原催化剂
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Series Reports from Professor Wei's Group of Chongqing University:Advancements in Electrochemical Energy Conversions(1/4):Report 1:High-performance Oxygen Reduction Catalysts for Fuel Cells
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作者 Fa-Dong Chen Zhuo-Yang Xie +5 位作者 Meng-Ting Li Si-Guo Chen Wei Ding Li Li Jing Li Zi-Dong Wei 《电化学(中英文)》 CAS 北大核心 2024年第7期1-27,共27页
Two major challenges,high cost and short lifespan,have been hindering the commercialization process of lowtemperature fuel cells.Professor Wei's group has been focusing on decreasing cathode Pt loadings without lo... Two major challenges,high cost and short lifespan,have been hindering the commercialization process of lowtemperature fuel cells.Professor Wei's group has been focusing on decreasing cathode Pt loadings without losses of activity and durability,and their research advances in this area over the past three decades are briefly reviewed herein.Regarding the Pt-based catalysts and the low Pt usage,they have firstly tried to clarify the degradation mechanism of Pt/C catalysts,and then demonstrated that the activity and stability could be improved by three strategies:regulating the nanostructures of the active sites,enhancing the effects of support materials,and optimizing structures of the three-phase boundary.For Pt-free catalysts,especialiy carbon-based ones,several strategies that they proposed to enhance the activity of nitrogen-/heteroatom-doped carbon catalysts are firstly presented.Then,an indepth understanding of the degradation mechanism for carbon-based catalysts is discussed,and followed by the corresponding stability enhancement strategies.Also,the carbon-based electrode at the micrometer-scale,faces the challenges such as low active-site density,thick catalytic layer,and the effect of hydrogen peroxide,which require rational structure design for the integral cathodic electrode.This review finally gives a brief conclusion and outlook about the low cost and long lifespan of cathodic oxygen reduction catalysts. 展开更多
关键词 Fuel cell Oxygen reduction reaction Pt-based catalyst Carbon-based catalyst
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Cu single-atom electrocatalyst on nitrogen-containing graphdiyne for CO_(2) electroreduction to CH_(4)
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作者 Hao Dai Tao Song +8 位作者 Xian Yue Shuting Wei Fuzhi Li Yanchao Xu Siyan Shu Ziang Cui Cheng Wang Jun Gu Lele Duan 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期123-132,共10页
Developing Cu single-atom catalysts(SACs)with well-defined active sites is highly desirable for producing CH4 in the electrochemical CO_(2) reduction reaction and understanding the structure-property relationship.Here... Developing Cu single-atom catalysts(SACs)with well-defined active sites is highly desirable for producing CH4 in the electrochemical CO_(2) reduction reaction and understanding the structure-property relationship.Herein,a new graphdiyne analogue with uniformly distributed N_(2)-bidentate(note that N_(2)-bidentate site=N^N-bidentate site;N_(2)≠dinitrogen gas in this work)sites are synthesized.Due to the strong interaction between Cu and the N_(2)-bidentate site,a Cu SAC with isolated undercoordinated Cu-N_(2) sites(Cu1.0/N_(2)-GDY)is obtained,with the Cu loading of 1.0 wt%.Cu1.0/N_(2)-GDY exhibits the highest Faradaic efficiency(FE)of 80.6% for CH_(4) in electrocatalytic reduction of CO_(2) at-0.96 V vs.RHE,and the partial current density of CH_(4) is 160 mA cm^(-2).The selectivity for CH_(4) is maintained above 70% when the total current density is 100 to 300 mA cm^(-2).More remarkably,the Cu1.0/N_(2)-GDY achieves a mass activity of 53.2 A/mgCu toward CH4 under-1.18 V vs.RHE.In situ electrochemical spectroscopic studies reveal that undercoordinated Cu-N_(2) sites are more favorable in generating key ^(*)COOH and ^(*)CHO intermediate than Cu nanoparticle counterparts.This work provides an effective pathway to produce SACs with undercoordinated Metal-N_(2) sites toward efficient electrocatalysis. 展开更多
关键词 Carbon dioxide reduction ELECTROCATALYSIS Cu single-atom catalyst N-containing graphdiyne Methane
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石墨烯催化材料显“神”效
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作者 王熙庭 《天然气化工—C1化学与化工》 CAS CSCD 北大核心 2016年第2期67-67,共1页
石墨烯这一神奇材料,在催化领域的应用研究也受到越来越多的重视,并显示出好效果。日前文献报道(Nano Energy(2016).DOI:10.1016/j.nanoen.2016.03.024),一种新型的参杂Cu纳米粒子的富氮石墨烯复合催化剂,可高效和高选择性地将二... 石墨烯这一神奇材料,在催化领域的应用研究也受到越来越多的重视,并显示出好效果。日前文献报道(Nano Energy(2016).DOI:10.1016/j.nanoen.2016.03.024),一种新型的参杂Cu纳米粒子的富氮石墨烯复合催化剂,可高效和高选择性地将二氧化碳转化为乙烯。 展开更多
关键词 石墨烯 催化材料 复合催化剂 参杂 氧化还原催化剂 文献报道 应用研究 催化剂 催化活性 羟甲基糠醛
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Chalcogen heteroatoms doped nickel-nitrogen-carbon single-atom catalysts with asymmetric coordination for efficient electrochemical CO_(2) reduction
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作者 Jialin Wang Kaini Zhang +5 位作者 Ta Thi Thuy Ng Yiqing Wang Yuchuan Shi Daixing Wei Chung-Li Dong Shaohua Shen 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期54-65,共12页
The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2) reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into... The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2) reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into the symmetric nickel-nitrogen-carbon(Ni-N_(4)-C)configuration to obtain Ni-X-N_(3)-C(X:S,Se,and Te)SACs with asymmetric coordination presented for central Ni atoms.Among these obtained Ni-X-N_(3)-C(X:S,Se,and Te)SACs,Ni-Se-N_(3)-C exhibited superior eCO_(2)RR activity,with CO selectivity reaching~98% at-0.70 V versus reversible hydrogen electrode(RHE).The Zn-CO_(2) battery integrated with Ni-Se-N_(3)-C as cathode and Zn foil as anode achieved a peak power density of 1.82 mW cm^(-2) and maintained remarkable rechargeable stability over 20 h.In-situ spectral investigations and theoretical calculations demonstrated that the chalcogen heteroatoms doped into the Ni-N_(4)-C configuration would break coordination symmetry and trigger charge redistribution,and then regulate the intermediate behaviors and thermodynamic reaction pathways for eCO_(2)RR.Especially,for Ni-Se-N_(3)-C,the introduced Se atoms could significantly raise the d-band center of central Ni atoms and thus remarkably lower the energy barrier for the rate-determining step of ^(*)COOH formation,contributing to the promising eCO_(2)RR performance for high selectivity CO production by competing with hydrogen evolution reaction. 展开更多
关键词 Electrochemical CO_(2) reduction reaction Chalcogen heteroatoms Single-atom catalysts Asymmetric coordination CO production
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乳化剂和破乳剂
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作者 李洪华 龚小芬 孙占宁 《精细石油化工文摘》 CAS 1994年第3期36-44,共9页
关键词 化剂 破乳剂 复配物 蔗糖脂肪酸酯 乳化性能 丙烯酸酯共聚物 聚甘油脂肪酸酯 聚合速率 部分水解 氧化还原催化剂
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无催化剂/添加剂条件下芳酰基杂环化合物的光化学合成 被引量:1
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作者 陈泽乐 宣俊 《有机化学》 SCIE CAS CSCD 北大核心 2022年第3期923-924,共2页
在过去的十几年里,可见光诱导的有机化学转化得到了长足的发展,其绿色温和的反应模式在新反应设计、天然产物合成、功能材料开发等领域扮演着越来越重要的角色[1].通常,可见光催化反应依赖于使用铱、钌等贵金属配合物或有机染料作催化剂... 在过去的十几年里,可见光诱导的有机化学转化得到了长足的发展,其绿色温和的反应模式在新反应设计、天然产物合成、功能材料开发等领域扮演着越来越重要的角色[1].通常,可见光催化反应依赖于使用铱、钌等贵金属配合物或有机染料作催化剂,通过光氧化还原途径实现各种化学转化.然而,光催化剂一般价格昂贵且在反应结束后难以回收,这些都限制了光催化技术的发展和进一步应用.因此,开发单一可见光照射下(不使用光氧化还原催化剂)底物向目标产物的高效转化,逐渐成为合成光化学领域的热门研究方向[2]. 展开更多
关键词 氧化还原催化剂 杂环化合物 光化学合成 有机化学 金属配合物 可见光催化 可见光照射 反应模式
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Effect of preparation routes on activity of Ag-MnO_x/C as electrocatalysts for oxygen reduction reaction in alkaline media 被引量:2
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作者 伍秋美 阮建明 +1 位作者 周忠诚 桑商斌 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第2期510-519,共10页
The effect of preparation routes on the physical characteristics and activity of the Ag-MnOx/C composites toward the oxygen reduction reaction (ORR) in alkaline media were studied by X-ray diffraction (XRD), X-ray... The effect of preparation routes on the physical characteristics and activity of the Ag-MnOx/C composites toward the oxygen reduction reaction (ORR) in alkaline media were studied by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy-dispersion spectroscopy (EDS) as well as scanning electron microscopy (SEM) and electrochemical techniques. The results show that more Ag and Mn species present on the surface of the Ag-MnOx/C composite prepared by two-step route (Ag-MnOx/C-2) compared to the one prepared by one-step route (Ag-MnOx/C-1), which contributes to its superior activity toward the ORR. The higher electron transfer number involved in the ORR can be observed on the Ag-MnOx/C-2 composite and its specific mass kinetic current at -0.6 V (vs Hg/HgO) is 46 mA/μg, which is 23 times that on the Ag/C. The peak power density of zinc-air battery with the Ag-MnOx/C-2 air electrode reaches up to 117 mW/cm^2. 展开更多
关键词 SILVER manganese oxide oxygen reduction reaction zinc-air battery ELECTROCATALYST full cell
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Selective reduction of carbon dioxide to carbon monoxide over Au/CeO_2 catalyst and identification of reaction intermediate 被引量:1
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作者 朱晓兵 曲新 +4 位作者 李小松 刘景林 刘剑豪 朱斌 石川 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第12期2053-2058,共6页
CO2 selective reduction to CO with H2 over a CeO2-supported nano-Au catalyst at atmospheric pres- sure was investigated. A high CO2 conversion, approaching the thermodynamic equilibrium value, and nearly 100% CO selec... CO2 selective reduction to CO with H2 over a CeO2-supported nano-Au catalyst at atmospheric pres- sure was investigated. A high CO2 conversion, approaching the thermodynamic equilibrium value, and nearly 100% CO selectivity were obtained. The surface formate intermediates generated during the reverse water-gas shift reaction at 400 ℃ were identified using in situ diffuse-reflectance infra- red Fourier-transform spectroscopy. The formate consumption to give CO and H20, determined using mass spectrometry, indicated that the reaction proceeded via an associative formate mecha- nism; this contributes to the high Au/CeO2 catalytic activity at low temperatures. 展开更多
关键词 CO2 reductionAu/CeO2 catalystCarbon monoxide Formate intermediate In situ DRIFT spectroscopy
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Chemoselective Transfer Hydrogenation of Cinnamaldehyde over Activated Charcoal Supported Pt/Fe3O4 Catalyst 被引量:1
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作者 张勇 陈春 +5 位作者 龚万兵 宋杰瑶 苏燕平 张海民 汪国忠 赵惠军 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第4期467-473,I0002,共8页
A variety of spherical and structured activated charcoal supported Pt/Fe3O4 composites with an average particle size of ~100 nm have been synthesized by a self-assembly method using the difference of reduction potenti... A variety of spherical and structured activated charcoal supported Pt/Fe3O4 composites with an average particle size of ~100 nm have been synthesized by a self-assembly method using the difference of reduction potential between Pt (Ⅳ) and Fe (Ⅱ) precursors as driving force. The formed Fe3O4 nanoparticles (NPs) effectively prevent the aggregation of Pt nanocrystallites and promote the dispersion of Pt NPs on the surface of catalyst, which will be favorable for the exposure of Pt active sites for high-efficient adsorption and contact of substrate and hydrogen donor. The electron-enrichment state of Pt NPs donated by Fe304 nanocrystallites is corroborated by XPS measurement, which is responsible for promoting and activating the terminal C=O bond of adsorbed substrate via a vertical configuration. The experimental results show that the activated charcoal supported Pt/Fe3O4 catalyst exhibits 94.8% selectivity towards cinnamyl alcohol by the transfer hydrogenation of einnamaldehyde with Pt loading of 2.46% under the optimum conditions of 120 ℃ for 6 h, and 2-propanol as a hydrogen donor. Additionally, the present study demonstrates that a high-efficient and recyclable catalyst can be rapidly separated from the mixture due to its natural magnetism upon the application of magnetic field. 展开更多
关键词 Activated charcoal supported Pt/Fe3O4 catalysts Redox method Transfer hydrogenation Cinnamaldehyde Cinnamyl alcohol
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Fe-Mn/Al_2O_3 catalysts for low temperature selective catalytic reduction of NO with NH_3 被引量:7
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作者 王晓波 伍士国 +3 位作者 邹伟欣 虞硕涵 归柯庭 董林 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1314-1323,共10页
A series of Fe‐Mn/Al2O3 catalysts were prepared and studied for low temperature selective catalytic reduction (SCR) of NO with NH3 in a fixed‐bed reactor. The effects of Fe and Mn on NO conversion and the deactiva... A series of Fe‐Mn/Al2O3 catalysts were prepared and studied for low temperature selective catalytic reduction (SCR) of NO with NH3 in a fixed‐bed reactor. The effects of Fe and Mn on NO conversion and the deactivation of the catalysts were studied. N2 adsorption‐desorption, X‐ray diffraction, transmission electron microscopy, energy dispersive spectroscopy, H2 temperature‐programmed reduction, NH3 temperature‐programmed desorption, X‐ray photoelectron spectroscopy (XPS), thermal gravimetric analysis and Fourier transform infrared spectroscopy were used to character‐ize the catalysts. The 8Fe‐8Mn/Al2O3 catalyst gave 99%of NO conversion at 150?? and more than 92.6%NO conversion was obtained in a wide low temperature range of 90–210??. XPS analysis demonstrated that the Fe3+was the main iron valence state on the catalyst surface and the addition of Mn increased the accumulation of Fe on the surface. The higher specific surface area, enhanced dispersion of amorphous Fe and Mn, improved reduction properties and surface acidity, lower binding energy, higher Mn4+/Mn3+ratio and more adsorbed oxygen species resulted in higher NO conversion for the 8Fe‐8Mn/Al2O3 catalyst. In addition, the SCR activity of the 8Fe‐8Mn/Al2O3 cata‐lyst was only slightly decreased in the presence of H2O and SO2, which indicated that the catalyst had better tolerance to H2O and SO2. The reaction temperature was crucial for the SO2 resistance of catalyst and the decrease of catalytic activity caused by SO2 was mainly due to the sulfate salts formed on the catalyst. 展开更多
关键词 Nitrogen monoxide Low-temperature selective catalytic reduction Fe-Mn catalyst X-ray photoelectron spectroscopy Sulfur dioxide Fourier transform infrared spectroscopy
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生产绿色苯乙烯
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作者 阮并元(摘译) 《石油石化绿色低碳》 2021年第3期70-70,共1页
北卡罗来纳州立大学研究团队发明了一种新型氧化还原催化剂,由铁酸钾表面外壳包裹着钙锰氧化物核构成。传统乙苯制备苯乙烯工艺收率约为54%,通常需要向发生转化的反应器提供高温和蒸汽,蒸汽提供热量并将反应平衡推向苯乙烯方向。该新型... 北卡罗来纳州立大学研究团队发明了一种新型氧化还原催化剂,由铁酸钾表面外壳包裹着钙锰氧化物核构成。传统乙苯制备苯乙烯工艺收率约为54%,通常需要向发生转化的反应器提供高温和蒸汽,蒸汽提供热量并将反应平衡推向苯乙烯方向。该新型催化剂苯乙烯收率能达到91%,转化过程同样在高温下进行,但不需要蒸汽。 展开更多
关键词 乙烯收率 反应平衡 氧化还原催化剂 氧化 苯乙烯 新型催化剂 乙苯制备 研究团队
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纸张用涂料
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《涂料文摘》 1997年第1期57-57,共1页
关键词 纸张用涂料 乳液聚合 甲基丙烯酸甲 乙烯基单体 记录介质 水性树脂 氧化还原催化剂 硅氧烷 日本专利 乙烯基聚合物
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Preparation of nitrogen-doped carbon nanoblocks with high electrocatalytic activity for oxygen reduction reaction in alkaline solution 被引量:2
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作者 张亭亭 何传生 +1 位作者 黎琳波 林雨青 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1275-1282,共8页
The oxygen reduction reaction (ORR) is traditionally performed using noble‐metals catalysts, e.g. Pt. However, these metal‐based catalysts have the drawbacks of high costs, low selectivity, poor stabili‐ties, and... The oxygen reduction reaction (ORR) is traditionally performed using noble‐metals catalysts, e.g. Pt. However, these metal‐based catalysts have the drawbacks of high costs, low selectivity, poor stabili‐ties, and detrimental environmental effects. Here, we describe metal‐free nitrogen‐doped carbon nanoblocks (NCNBs) with high nitrogen contents (4.11%), which have good electrocatalytic proper‐ties for ORRs. This material was fabricated using a scalable, one‐step process involving the pyrolysis of tris(hydroxymethyl)aminomethane (Tris) at 800℃. Rotating ring disk electrode measurements show that the NCNBs give a high electrocatalytic performance and have good stability in ORRs. The onset potential of the catalyst for the ORR is-0.05 V (vs Ag/AgCl), the ORR reduction peak potential is-0.20 V (vs Ag/AgCl), and the electron transfer number is 3.4. The NCNBs showed pronounced electrocatalytic activity, improved long‐term stability, and better tolerance of the methanol crosso‐ver effect compared with a commercial 20 wt%Pt/C catalyst. The composition and structure of, and nitrogen species in, the NCNBs were investigated using Fourier‐transform infrared spectroscopy, scanning electron microscopy, X‐ray photoelectron spectroscopy, and X‐ray diffraction. The pyroly‐sis of Tris at high temperature increases the number of active nitrogen sites, especially pyridinic nitrogen, which creates a net positive charge on adjacent carbon atoms, and the high positive charge promotes oxygen adsorption and reduction. The results show that NCNBs prepared by pyrolysis of Tris as nitrogen and carbon sources are a promising ORR catalyst for fuel cells. 展开更多
关键词 Nitrogen-doped carbon nanoblock Trihydroxymethyl aminomethane ELECTROCATALYST Oxygen reduction reaction NANOCATALYST
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A mesoporous Fe/N/CORR catalyst for polymer electrolyte membrane fuel cells 被引量:3
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作者 石尉 王宇成 +3 位作者 陈驰 杨晓冬 周志有 孙世刚 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第7期1103-1108,共6页
Fe/N/C is a promising non-platinum catalyst for the oxygen reduction reaction (ORR). Even so, mass transfer remains a challenge in the application of Fe/N/C to proton exchange membrane fuel cells, due to the high ca... Fe/N/C is a promising non-platinum catalyst for the oxygen reduction reaction (ORR). Even so, mass transfer remains a challenge in the application of Fe/N/C to proton exchange membrane fuel cells, due to the high catalyst loadings required. In the present work, mesoporous Fe/N/C was syn- thesized through heat treatment of K]600 carbon black coated with poly-2-aminobenzimidazole and FeC13. The as-prepared Fe/N/C possesses a unique hollow-shell structure that contains a buffer zone allowing both water formation and vaporization, and also facilitates the mass transfer of gas- eous oxygen. This catalyst generated an oxygen reduction reaction activiW of 9.21 A/g in conjunc- tion with a peak power density of 0.71 W/cm2. 展开更多
关键词 Fe/N/C catalystNon-platinum catalystOxygen reduction reactionMesoporeHollow-shell structure
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Visible light promoted difunctionalization reactions of alkynes 被引量:3
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作者 Xiang Ren Zhan Lu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第7期1003-1019,共17页
Visible light promoted difunctionalization of alkynes is reviewed. The difunctionalization reaction is achieved by different reagents. Radicals such as carbon(sp3), carbon(sp2), and other heteroatom(P, S, N, Se, O, an... Visible light promoted difunctionalization of alkynes is reviewed. The difunctionalization reaction is achieved by different reagents. Radicals such as carbon(sp3), carbon(sp2), and other heteroatom(P, S, N, Se, O, and halide) radicals initiated by visible light can undergo radical addition to a carbon-carbon triple bond. Upon further transformation, the desired difunctionalized products are obtained. Some organometallic complexes can be activated by visible light;the difunctionalization of alkynes is catalyzed by these species. Other reagents like 1,3-dipole precursors could also react with alkynes to give difunctionalization products;here, the 1,3-dipole derivatives are obtained by visible light photocatalysis. So far, the strategy has been succeeded in the formation of C–C bonds and C–X bonds. Several valuable chemical skeletons have been constructed under mild conditions. However, high regio-and stereoselectivities in some direct difunctionalization methodologies are yet to be achieved. 展开更多
关键词 Visible light photocatalysis Difunctionalization CYCLIZATION ALKYNE Redox catalyst
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