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Inside-out dual-doping effects on tubular catalysts:Structural and chemical variation for advanced oxygen reduction performance

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Nano Research 2022年第1期15卷 361-367页

作者： Yang Gao Debin Kong Jiaxu Liang Daliang Han Bin Wang Quan-Hong Yang Linjie Zhi CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China University of Chinese Academy of Sciences Beijing 100049China

Dual-doping of carbon,especially the combination of nitrogen and a secondary heteroatom,has been demonstrated efficient to optimize the oxygen reduction reaction(ORR)performance.However,the optimum dual-doping is still not clear due to the lack of strong experimental proofs,which rely on a reliable method to prepare carbon materials that can rule out the interference factors and then emphasize only the doping effects.In this work,an inside-out doping method is reported to prepare carbon submicrotubes(CSTs)as a material to study the principles of designing dual-doping catalysts for ORR.The interference factors including the metal impurities and doping gradient in the bulk phase are excluded,and the doping effects including the structural and chemical variation of carbon are studied.P-doping exhibited a higher pore-forming ability to perforate carbon and a lower doping content,but a higher ORR catalytic activity as compared with S-and B-doped N-CSTs,demonstrating the N,P co-doping is more efficient in making carbon-based catalysts for ORR.First-principle calculations reveal that the edge C situated around the oxidized P site nearby a graphitic N atom is the active site that shows the lowest ORR overpotential comparable to Pt-based catalysts.This study suggests that the catalytic activity of dual-heteroatoms-doped carbons not only depends on the intrinsic chemical bonding between heteroatoms and carbon,but also is affected by the structural variation generated by introducing different atoms,which can be extended to the study of other kinds of functionalization of carbon and potential reactions besides ORR.

关键词： dual-doping phosphorus carbon tubes oxygen reduction metal-free catalysts

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Biomass-based N doped carbon as metal-free catalyst for selective oxidation of D-xylose into D-xylonic acid

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Green Energy & Environment 2022年第6期7卷 1310-1317页

作者： Zengyong Li Yiming Huang Xiao Chi Di Li Linxin Zhong Xuehui Li Chuanfu Liu Xinwen Peng State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou510640China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou510640China

Rational design and facile preparation of low-cost and efficient catalysts for the selective converting of biomass-derived monosaccharides into high value-added chemicals is highly demanded,yet challenging.Herein,we first demonstrate a N doped defect-rich carbon(NC-800-5)as metal-free catalyst for the selective oxidation of D-xylose into D-xylonic acid in alkaline aqueous solution at 100℃ for 30 min,with 57.4%yield.The doped graphitic N is found to be the active site and hydroxyl ion participating in the oxidation of D-xylose.Hydroxyl ion and D-xylose first adsorb on NC-800-5 surface,and the aldehyde group of D-xylose is catalyzed to form germinal diols ion.Then,C–H bond break to yield carboxylic group.Furthermore,NC-800-5 catalyst shows high stability in recycled test.

关键词： Biomass carbon metal-free catalysts D-xylose Sugar acid Selective oxidation

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Tailoring the Porous Structure of Mono-dispersed Hierarchically Nitrogen-doped Carbon Spheres for Highly Efficient Oxygen Reduction Reaction

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Energy & Environmental Materials 2021年第1期4卷 81-87页

作者： Chengyong Shu Zhuofan Gan Yuyang Hou Ting Zhu Jijun Ma Wei Tang Yuping Wu School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an 710049China CSIRO Mineral Resources Clayton Vic 3168Australia School of Materials Science and Engineering Central South UniversityChangsha 410083China State Key Laboratory of Space Power-Sources Technology Shanghai Institute of Space Power-SourcesShanghai 200245China State Key Laboratory of Materials-Oriented Chemical Engineering School of Energy Science and Engineering and Institute of Advanced MaterialsNanjing Tech UniversityNanjing 211800China

The search for a low-cost metal-free cathode material with excellent mass transfer structure and catalytic activity in oxygen reduction reaction(ORR)is one of the most challenging issues in fuel cells.In this work,nitrogen-rich mphenylenediamine is introduced into the synthesis of porous carbon spheres to tune the pore structure and nitrogen-doped active sites.As a result,more pyridinic N and pyrrolic N functional species were observed at the interior and surface of the carbon spheres.The introduction of m-phenylenediamine also regulated the nucleating of precursors,an urchin-like mesoporous surface structure ensures point contact and less agglomeration between each particle was obtained.With optimized proportion of micropores/mesopores and improved nitrogen-contained functional species,the ORR activity can be remarkably improved.The half-wave potential of this catalyst could achieve to 0.81 V(versus RHE)which is only 42 m V lower than commercial Pt/C catalyst.Furthermore,the optimized cathode catalyst achieved a 69 m W cm-2 maximum power density when operated in direct methanol fuel cells at room temperature.

关键词： fuel cells metal-free catalysts nitrogen-doped porous carbon oxygen reduction reaction

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Nitrogen-Doped Graphene Foam as a metal-free Catalyst for Reduction Reactions under a High Gravity Field

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Engineering 2020年第6期6卷 680-687页

作者： Zhiyong Wang Zhijian Zhao Jesse Baucom Dan Wang Liming Dai Jian-Feng Chen State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Department of Chemical and Biomolecular Engineering University of CaliforniaLos AngelesCA 90095USA Center of Advanced Science and Engineering for Carbon(Case4Carbon) Department of Macromolecular Science and EngineeringCase School of EngineeringCase Western Reserve UniversityClevelandOH 44106USA Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China

Herein,we report on the effect of a high gravity field on metal-free catalytic reduction,taking the nitrobenzene(NB)reduction and methylene blue(MB)degradation as model reactions in a highgravity rotating tube reactor packed with three-dimensional(3D)nitrogen-doped graphene foam(NGF)as a metal-free catalyst.The apparent rate constant(kapp)of the metal-free catalytic reduction of NB in the rotating tube reactor under a high gravity level of 6484g(g=9.81 m s-2)was six times greater than that in a conventional stirred reactor(STR)under gravity.Computational fluid dynamics(CFD)simulations indicated that the improvement of the catalytic efficiency was attributed to the much higher turbulent kinetic energy and faster surface renewal rate in the high-gravity tube reactor in comparison w让h those in a conventional STR.The structure of the 3D metal-free catalysts was stable during the reaction process under a high gravity field,as confirmed by X-ray photoelectron spectroscopy(XPS)and Raman spectra.In the other model reaction,the rate of MB degradation also increased as the high gravity level in creased gradually,which aligns with the result for the NB catalytic reduction system.These results demonstrate the potential to use a high-gravity rotating packed tube reactor for the process intensification of metal-free catalytic reduction reactions.

关键词： High-gravity technology Process intensification metal-free catalysts Carbon nanomateriais Catalytic reduction

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探讨非金属氮掺杂石墨炔中氧还原电化学反应的活性位点（英文）

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Science Bulletin 2020年第1期65卷 45-54,M0004页

作者：陈星竹王伟俊孔周舟赵修建李能 State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology Wuhan 430070 China School of Energy and Chemical Engineering Xiamen University Malaysia Sepang Selangor Darul Ehsan 43900 Malaysia College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

开发高效、低成本的电化学反应催化剂是可再生能源技术研究的热点之一.本文采用密度泛函理论(DFT)系统地研究了grap-N,sp-N(Ⅰ)和spN(Ⅱ)三种位置的氮掺杂对不含金属的石墨炔(GDY)氧还原电催化剂性能的影响.研究表明,GDY中掺杂的氮原子... 详细信息

开发高效、低成本的电化学反应催化剂是可再生能源技术研究的热点之一.本文采用密度泛函理论(DFT)系统地研究了grap-N,sp-N(Ⅰ)和spN(Ⅱ)三种位置的氮掺杂对不含金属的石墨炔(GDY)氧还原电催化剂性能的影响.研究表明,GDY中掺杂的氮原子通过活化其相邻的碳原子,可以显著提高GDY的氧气(O2)吸附活性.采用自由能图描述电化学氧还原反应(ORR)的解离(dissociation)和结合(association)机制.结果表明,在大多数底物上结合机制比解离机制能提供更高的ORR起始电位.其中,sp-N(Ⅱ)掺杂GDY的理论起始电位为0.76 V,表现出最高的ORR电催化活性.本文为不含金属的N掺杂GDY的电化学ORR机理提供了原子水平的理解.

关键词： Graphdiyne(GDY) Site-specific nitrogen doping metal-free catalysts Oxygen reduction reaction(ORR)

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环三磷腈衍生物的合成及其吸附和降解性能

环三磷腈衍生物的合成及其吸附和降解性能

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2012年全国高分子材料科学与工程研讨会

作者：李贞可宋明星刘书正张爱清中南民族大学化学与材料科学学院武汉科技大学化学工程与技术学院

＜正＞环境污染成为世界各国普遍面临且亟待解决的问题之一。选择和开发高效、环保、经济的催化剂来降解污染物,又成为治理环境污染的关键。近年来,学者们对半导体金属氧化物进行了深入的研究,制备了不同种类和形貌的催化剂,在光的作用... 详细信息

＜正＞环境污染成为世界各国普遍面临且亟待解决的问题之一。选择和开发高效、环保、经济的催化剂来降解污染物,又成为治理环境污染的关键。近年来,学者们对半导体金属氧化物进行了深入的研究,制备了不同种类和形貌的催化剂,在光的作用下,取得了较好的催化降

关键词： Cyclotriphosphazene metal-free catalysts Methylene blue

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