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Homogeneous Zr and Ti co-doped SBA-15 with high specific surface area:preparation,characterization and application

2004年国际稀土研究应用研讨会

作者： Liu Zhaogang, Liu Lmgsheng, Hu Yanhong, Xiong Xiaobai Baotou Research Institute of Rare Earths

The Y2O3 ultrafine powder with high specific surface area were prepared by the precipitation-calcination method. Urea-ammonia were used as the precipitant. The precursors were washed with water, then dried at 80℃in vacuum and calcined at 650℃to produce Y2O3 ultrafine powder with high specific surface area. The effect of concentrations of ammonia, concentrations of urea and adding rate of precipitant on particle size and specific surface area of Y2O3 had been investigated. According to the results of the experiment, when rise the concentrations of ammonia, the particle size of Y2O3 rises quickly and specific surface area of Y2O3 decreases;when rise the concentrations of urea, the particle size of Y2O3 is constant almost and specific surface area of Y2O3 rises slightly;the adding rate of precipitant have slight influence on particle size and specific surface area of Y2O3. The Y2O3 ultrafine powder with specific surface area more then 50m2/g, particle size 90nm were synthesized at optimum reaction conditions. From the results obtained, it can be concluded that the process is a promising process for the preparation of Y2O3 ultrafine powder with high specific surface area.

关键词： Y2O3 ultrafine Powder high specific surface area preparation

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Journal of Leather Science and Engineering 2019年第1期1卷 1-12页

作者： Taotao Qiang Yajuan Xia Jing Zhao College of Bioresources and Materials Engineering Shaanxi University of Science&TechnologyXi’anShaanxi 710021People’s Republic of China National Demonstration Center for Experimental Light Chemistry Engineering Education Shaanxi University of Science&TechnologyXi’anShaanxi 710021People’s Republic of China

A facile synthesis procedure is proposed to prepare homogeneous Zr and Ti co-doped SBA-15(Zr-Ti-SBA-15)with high specific surface area of 876.0m2 g−*** on“masking mechanism”from tanning,lactic acid was used as masking agent to obtain the uniform distribution of Zr and Ti species in the SBA-15 *** obtained materials were characterized by powder X-ray diffraction(XRD),nitrogen adsorption-desorption isotherms,scanning electron microscope(SEM),transmission electron microscope(TEM)and X-ray photoelectron(XPS).The results reveal that in mesoporous materials,the presence of lactic acid gives rise to the uniform distribution of Zr and Ti *** adsorption equilibrium and kinetic studies of Zr-Ti-SBA-15 materials show that the adsorption process conforms to the Langmuir isotherm and pseudo-second-order kinetic model,*** experiments show that the Zr-Ti-SBA-15 displays a significant adsorption ability for methylene blue(MB)(up to 291.6 mg/g),along with good reusability,indicating promising potentials of ***,this work provides a wide range of possibilities for further development of SBA-15 based on bimetallic and sewage disposal.

关键词： Direct synthesis method Zr-Ti-SBA-15 Adsorption high specific surface area

Carbon cathode with heteroatom doping and ultrahigh surface area enabling enhanced capacitive behavior for potassium-ion hybrid capacitors

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Rare Metals 2024年第5期43卷 2136-2149页

作者： Yan Xiong Ya-Fei Zhang Chun-Liu Zhu Lei Yang Huan-Yu Liang Jing Shi Jing-Wei Chen Wei-QianTian Shuai Liu Zhi Li Jing-Yi Wu Huan-Lei Wang School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 2V4Canada

Potassium-ion hybrid capacitors(PIHCs)are widely regarded as highly promising energy storage devices,due to their exceptional energy density,impressive power density,and abundant potassium ***,restricted by the inherent capacitive storage mechanism,the carbon cathodes possess a much lower specific capacity than battery-type ***,designing high-performance carbon cathodes is extremely urgent for the development of ***,N,O codoped porous carbon(NOPC)was fabricated through the NaCl hard template method and combined KOH/melamine chemical activation technique,displaying the characteristics of abundant N/O content(4.7 at%/16.9 at%),ultrahigh specific surface area(3092 m^(2)g^(-1))and hierarchical pore *** designed NOPC cathode delivers a high specific capacity(164.4 mAh.g^(-1)at 0.05 A.g^(-1))and superior cyclability(95.1%retention ratio at 2 A·g^(-1)over 2500 cycles).Notably,the adjustable ratio of micropores to mesopores facilitates the achievement of the optimal bal-ance between capacity and rate ***,the pseudocapacitance can be further augmented through the incorporation of N/O functional *** expected,the graphite//NOPC based PIHC possesses a high energy density of 113 Wh·kg-at 747 W·kg^(-1)and excellent capacity retention of 84.4% fter 400 cycles at 1.0 A·g^(-1).This work introduces a novel strategy for designing carbon cathodes that enhances the electrochemical performance of PIHCs.

关键词： Template method N/O co-doping high specific surface area Carbon cathode Potassium-ion capacitors

Two-dimensional porous carbon derived from pollen with enlarged interlayer distance enhanced electrocatalytic oxidation of n-valeraldehyde to octane

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Nano Research 2024年第5期17卷 3455-3461页

作者： Meichun Qin Chaolong Liu Shouhen Xu Jianguo Tang Institute of Hybrid Materials National Center of International Joint Research for Hybrid Materials TechnologyNational Base of International Sci.and Tech.Cooperation on Hybrid MaterialsCollege of Materials Science and EngineeringQingdao UniversityQingdao266071China Department of Pharmaceutics School of PharmacyQingdao UniversityQingdao266071China

Electrocatalytic n-valeraldehyde oxidation reaction was an inexpensive and eco-friendly method to control n-valeraldehyde contamination and produce high value-added ***,low-cost and readily available electrocatalysts with high current efficiency were urgently ***,two-dimensional porous carbon derived from pollen with enlarged interlayer distance was built by alkali activation method,applying in electrocatalytic n-valeraldehyde oxidation *** enlarged interlayer distance was verified by X-ray diffraction(XRD)and high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM).Electrocatalytic experiments consequences showed activated biomass derived carbon possessed a higher electrocatalytic activity and octane selectivity than unactivated *** tests and in situ infrared experiments demonstrated that enlarged interlayer distance was positively correlated with specific surface area of catalysts,large specific surface area provided abundant absorption sites,facilitated the adsorption for n-valeraldehyde,and further promoted the transformation of n-valeraldehyde to *** work also provides a new avenue for creating high-performance electrocatalysts in terms of lattice engineering.

关键词： biomass derived carbon lattice expansion high specific surface area upgrade of n-valeraldehyde

Defect-rich and highly porous carbon nanosheets derived from Ti_(3)AlC_(2) MAX with good lithium storage properties

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Chinese Chemical Letters 2023年第2期34卷 618-622页

作者： Zhihao Zhu Peng Liu Yucheng Liu Xingxing Gu Zhi Su Zhong Su Chao Lai College of Chemistry and Chemical Engineering Xinjiang Normal UniversityUrumqi 830054China School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou 221116China Chongqing Key Laboratory of Catalysis and New Environmental Materials College of Environment and ResourcesChongqing Technology and Business UniversityChongqing 400067China National Research Base of Intelligent Manufacturing Service Chongqing Technology and Business UniversityChongqing 400067China

Defect-rich,highly porous two-dimensional carbon nanosheets(CNS) have attracted tremendous research interests in catalysis and environmental purification and other fields,because of their unique micromorphology,chemical stability and high specific surface ***,in this work,we report a new solution to synthesize an ultrathin two-dimensional CNS with rich defects and abundant pores via two-step etching the Ti_(3)AlC_(2)with the help of I2and *** CNS thickness,specific surface area and pore volume could be all tunable by adding the amount of *** the highest specific surface area and pore volume of the synthesized 2D CNS can be achieved 1134.4 m^(2)/g and 0.80 cm^(3)/g,with a thickness of only 0.64 nm and a yield of 35.9%.When employed as the anodes for lithium-ion batteries,the synthesized CNS anodes exhibit good cycling and rate *** work provides a novel and facile strategy for synthesizing highly porous and defective 2D carbon materials with good lithium storage properties.

关键词： Ti_(3)AlC_(2) Two-dimensional Carbon nanosheets Rich defect high specific surface area

PVP-assisted preparation of nitrogen doped mesoporous carbon materials for supercapacitors

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Journal of Materials Science & Technology 2020年第23期58卷 197-204页

作者： Juan Du Aibing Chen Yue Zhang Shuang Zong Haixia Wu Lei Liu College of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang050018China International Joint Laboratory of New Energy Hebei University of Science and TechnologyShijiazhuang050018China Institute for the Development of Energy for African Sustainability University of South Africaprivate bag X6 Florida 1710South Africa

The rich porous structure,high surface area and surface doping make nitrogen doping mesoporous carbon materials(N-MPC)attractive in various areas,including adsorption separation,electrochemical energy storage,catalysis and other ***,polyvinylpyrrolidone(PVP)is introduced into the polymerization process of assembly of phenol/formaldehyde(PF)resin by means of hydrogen bonds and electrostatic interaction,which not only leads to the formation of uniform mesopores,but also leads to the increase of specific surface area and nitrogen *** amount of PVP and annealing temperature has no obvious effect on morphology,but subsequently has effect on the specific surface area and pore *** appropriate PVP dosage and annealing temperature are adopted,the obtained N-MPC shows abundant mesoporous,high surface area and suitable nitrogen *** electrode materials in supercapacitor,the N-MPC shows good performance with high capacitance good stability and rate performance,presenting its excellent promising in energy storage.

关键词： PVP-assisted high specific surface area Nitrogen doping Phenol/formaldehyde resin Supercapacitor

Biomass-derived nitrogen self-doped porous activation carbon as an effective bifunctional electrocatalysts

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Chinese Chemical Letters 2021年第1期32卷 92-98页

作者： Yuanqing Sun Yiming Ouyang Jiaqing Luo Huihui Cao Xiang Li Jingwen Ma Jian Liu Yuanhao Wang Lin Lu State Key Laboratory of Heavy Oil and Beijing Key Lab of Oil&Gas Optical Detection Technology College of ScienceChina University of PetroleumBeijing 102249China Hoffmann Institute of Advanced Materials Shenzhen PolytechnicShenzhen 518055China Renewable Energy Research Group(RERG) Department of Building Services EngineeringThe Hong Kong Polytechnic UniversityHong KongChina

The strategy of adopting cheap precursors or abundant resources,which can be obtained directly from nature,is a simple and excellent method of introducing accessible research into environmentally friendly ***,this is also an urgent requirement for the sustainable development of green ***,we introduce a simplistic and expandable method to prepare metal-free biomassderived nitrogen self-doped porous activation carbon(N-PAC) with large specific surface area(S_(BET)=1300.58 m^(2)/g).Moreover,the manufactural electrocatalysts exhibit prominent oxygen reduction reaction(ORR) performance in all PH *** compared with the commercial Pt/C catalyst,the N-PAC/800 with a positive onset potential at 10 mA/cm^(2)(0.93 V),half-wave potential(0.87 V),and limiting current(6.34 mA/cm^(2)) bring to light excellent catalytic stability,selectivity,and much-enhanced methanol ***,the prepared electrocatalysts possess considerable hydrogen evolution reaction(HER) performance with a less onset potential of 0.218 V(acidic medium) and0.271 V(alkaline medium) respectively,which can show similar catalytic activity across the whole pH *** bifunctional electrocatalyst,with excellent electrocatalytic properties,resource-rich,low cost,and environmental-friendly,hold a promising application in energy conversion and reserve.

关键词： Biomass-derived high specific surface area Bifunctional electrocatalysts Metal-free Nitrogen-doped carbon

Bimetallic-organic coordination polymers to prepare N-doped hierarchical porous carbon for high performance supercapacitors

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Progress in Natural Science:Materials International 2019年第5期29卷 495-503页

作者： Danchen Fu Zeyu Chen Chuying Yu Xiaolan Song Wenbin Zhong School Minerals Processing and Bioengineering Central South University College of Materials Science and Engineering Hunan University

Single metal-organic coordination polymers have limited functions as precursors for porous carbon electrode *** construction of bimetallic organic coordination polymers can effectively utilize the advantages of each single metal-organic coordination polymer to improve the performance of the derived carbon ***,high performance nitrogen-doped porous carbon(BC;)have been produced by directly carbonizing bimetallic organic coordination polymers formed by 4,4’-bipyridine（BPD）reaction with Fe Cl;and NiCl;.The BC;exhibits high nitrogen content（12.66 at%）,large specific surface area(1049.51 m;g;)and hierarchical porous structure,which contributes to an excellent gravimetric specific gravity of 320.5 Fg;and 108%of specific capacitance retention after 10000 *** BC;assembled symmetrical supercapacitor shows an energy density of 18.3 Wh kg;at a power density of 350 W kg;.It is expected that the as-prepared N-doped porous carbon derived from bimetallic-organic coordination polymer is a promising electrode material for high performance energy storage devices.

关键词： Bimetallic-organic coordination polymers N-doped porous carbon high specific surface area Supercapacitors

Nitrogen-doped hierarchical few-layered porous carbon for efficient electrochemical energy storage

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Carbon Energy 2021年第2期3卷 349-359页

作者： Peng Wang Xiaohuan Qi Wei Zhao Meng Qian Hui Bi Fuqiang Huang State Key Laboratory of high Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghaiChina School of Physical Science and Technology ShanghaiTech UniversityShanghaiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular EngineeringPeking UniversityBeijingChina

Large surface area,high conductivity,and rich active site of carbon electrode materials are necessary characteristics for energy storage ***,high conductivity and high nitrogen doping of carbon electrode materials are difficult to ***,a facile method via the carbonization of nitrogen-containing Schiff base polymer has been developed to prepare high conductivity and high nitrogen-doped hierarchical porous *** organic components with a benzene ring structure in the polymer promote the formation of more sp^(2)-graphitized carbon,which is beneficial for the improvement of electrical ***-doped hierarchical porous carbon calcined at 900℃ under the NH3 atmosphere possesses high nitrogen content of 7.48 at%,a large specific surface area of 1613.2m2/g,and high electrical conductivity of 2.7 S/*** electrode materials in an aqueous-based supercapacitor,nitrogen-doped hierarchical porous carbon exhibits superior specific capacitance of 385 F/g at 1 A/g as well as excellent rate performance(242 and 215 F/g at a current density of 100 and 200 A/g,respectively).In addition,the specific capacitance of electrode measured in a two-electrode system is 335 F/g at 1 A/g,and the long-term cycling stability can be achieved with more than 94%initial capacitance after 10000 *** constructed symmetric supercapacitor delivers high energy density and high power *** outstanding electrochemical performances combined with the novel and scalable synthetic approach make the nitrogen‐doped hierarchical porous carbon potential electrode material for electrochemical devices.

关键词： hierarchical porous carbon high specific surface area nitrogen-doped rate performance supercapacitor