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Molten Salts Strategy for the Synthesis of CoP Nanoparticles Entrapped,N,P co-Doped Mesoporous Carbons as Electrocatalysts for Hydrogen Evolution

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Chemical Research in Chinese Universities 2022年第1期38卷 237-242页

作者： XU Jing MIAO Sijia TANG Duihai ZHANG Wenting ZHAO Zhen QIAO Zhen-An Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034P.R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012P.R.China

Amolten salt process was developed to prepare CoP nanoparticles(NPs) embedded, N,P co-doped carbons with the combination of hand milling and high temperature carbonization. The characterization results implied that the as-prepared samples possessed mesoporous structures. Moreover, the mass ratios of the precursors affected the crystalline structures and the porosities of the final electrocatalysts. The as-prepared catalysts exhibited excellent electrocatalytic performances towards hydrogen evolution reaction(HER) under acidic and alkaline conditions. The as-prepared samples were designed as GxMyCoz, where x, y and z meant the amounts of glucose, melamine and CoCl2, respectively. The optimum sample of G6.0M2.0Co5.0 showed the best HER property with a low onset overpotential and a small Tafel slope, as well as excellent electrocatalytic stability.

关键词： CoP nanoparticle mesopore N P co-doped carbon Hydrogen evolution reaction Molten salt

Fabrication of a nano-sized ZSM-5 zeolite with intercrystalline mesopores for conversion of methanol to gasoline

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Journal of Energy Chemistry 2017年第1期26卷 139-146页

作者： Tingjun Fu Jiangwei Chang Juan Shao Zhong Li Key Laboratory of Coal Science and Technology Ministry of Education and Shanxi ProvinceTaiyuan University of TechnologyTaiyuan 030024ShanxiChina

Carbon deposition during methanol to hydrocarbons leads to the quick deactivation of ZSM-5 catalyst and it is one of the major problems for this technology. Decreasing the crystal size or introducing mesopores into ZSM-5 zeolites can improve its diffusion property and decrease the coke formation. In this paper, nano-sized ZSM-5 zeolite with intercrystalline mesopores combining the mesoporous and nano sized structure was fabricated. For comparison, the mesoporous ZSM-5 and nano-sized ZSM-5 were also prepared. These catalyst samples were characterized by XRD, BET, NH3-TPD, TEM, Py-IR and TG techniques and used on the conversion of methanol to gasoline in a fixed-bed reactor at T=405 degrees C, WHSV =4.74 h(-1) and P=1.0 MPa. It was found that the external surface area of the nano-sized ZSM-5 zeolite with intercrystalline mesopores reached 104 m(2)/g, larger than that of mesoporous ZSM-5 (66 m(2)/g) and nano sized ZSM-5 (76 m(2)/g). Catalytic lifetime of the nano-sized ZSM-5 zeolite with intercrystalline mesopores was 93 h, which was only longer than that of mesoporous ZSM-5 (86 h), but shorter than that of nano sized ZSM-5 (104 h). Strong acidity promoted the coke formation and thus decreased the catalytic lifetime of the nano-sized ZSM-5 zeolite with intercrystalline mesopores though it presented large external surface that could improve the diffusion property. The special zeolite catalyst was further dealuminated to decrease the strong acidity. After this, its coke formation rate was slowed and catalytic lifetime was prolonged to 106 h because of the large external surface area and decreased weak acidity. This special structural zeolite is a potential catalyst for methanol to gasoline reaction. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

关键词： ZSM-5 Crystal size mesopore Acidity Methanol to gasoline

Postsynthesis of hierarchical core/shell ZSM-5 as an efficient catalyst in ketalation and acetalization reactions

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Frontiers of Chemical Science and Engineering 2020年第2期14卷 258-266页

作者： Peng Luo Yejun Guan Hao Xu Mingyuan He Peng Wu Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China

Hierarchical core/shell Zeolite Socony Mobil-five(ZSM-5)zeolite was hydrothermally postsythesized in the solution of NaOH and diammonium surfactant via a dissolution-reassembly strategy.The silica and alumina species were firstly dissolved partially from the bulky ZSM-5 crystals and then were reassembled into the MFI-type nanosheets with the structure-directing effect of diammonium surfactant,attaching to the out-surface of ZSM-5 core crystals.The mesopores thus were generated in both the core and shell part,giving rise to a micropore/mesopore composite material.The micropore volume and the acidity of the resultant hybrid were well-preserved during this recrystallization process.Possessing the multiple mesopores and enlarged external surface area,the core/shell ZSM-5 zeolite exhibited higher activity in the ketalation and acetalization reactions involving bulky molecules in comparison to the pristine ZSM-5.

关键词： core/shell ZSM-5 in situ recrystallization mesopore ketalation and acetalization reactions

Mechanism of pore formation and structural characterization for mesoporous Mg-Al composite oxides

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Science China Chemistry 2002年第1期45卷 37-45页

作者：赵芸矫庆泽段雪 Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of Education Beijing Uni-versity of Chemical Technology Beijing China

Mg-AI layered double hydroxides (LDH) with different particle sizes were prepared using different aging times at high supersaturation by a new method developed in our laboratory. The key features of this method are a very rapid mixing and nucleation process followed by a separate aging process. By calcination of LDH at 500癈, mesoporous Mg-AI composite oxides with an extremely narrow pore size distribution were produced. The crystal structure of the Mg-AI composite oxides was a multiphasic one consisting of MgO-like crystals and a layered material.

关键词： layered double hydroxide Mg-Al composite oxide mesopore crystal structure.

General synthesis of hollow mesoporous conducting polymers by dual-colloid interface co-assembly for high-energy-density micro-supercapacitors

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Journal of Energy Chemistry 2021年第11期30卷 145-152,I0004页

作者： Jing Cui Fei-Fei Xing Hao Luo Jie-Qiong Qin Yan Li Yonghui Zhong Facai Wei Jianwei Fu Chengbin Jing Jiangong Cheng Zhong-Shuai Wu Shaohua Liu State Key Laboratory of Precision Spectroscopy and Department of Materials School of Physics and Electronic ScienceEast China Normal University500 Dongchuan RoadShanghai 200241China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences457 Zhongshan RoadDalian 116023LiaoningChina Dalian National Laboratory for Clean Energy Chinese Academy of Sciences457 Zhongshan RoadDalian 116023LiaoningChina University of Chinese Academy of Sciences 19 A Yuquan RoadShijingshan DistrictBeijing 100049China School of Chemistry and Molecular Engineering East China Normal University500 Dongchuan RoadShanghai 200241China School of Materials Science and Engineering Zhengzhou University100 Science AvenueZhengzhou 450002HenanChina State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences865 Changning RoadShanghai 200050China Shanghai Academy of Quality Management 258 Wuyi RoadShanghai 200050China

Rational design and precise regulation over the morphology, structure, and pore size of functional conducting mesoporous polymers with enriched active sites and shorten electron–ion transport pathway are extremely important for developing high-performance micro-supercapacitors (MSCs), but still remain a great challenge. Herein, a general dual-colloid interface co-assembly strategy is proposed to fabricate hollow mesoporous polypyrrole nano-bowls (mPPy-nbs) for high-energy-density solid-state planar MSCs. By simply adjusting the size of block copolymer micelles, the diameter of polystyrene nanospheres and the amount of pyrrole monomer, mesopore size of the shell, void and shell thickness of mPPy-nbs can be simultaneously controlled. Importantly, this strategy can be further utilized to synthesize other hollow mesoporous polymers, including poly(tris(4-aminophenyl)amine), poly(1,3,5-triaminobenzene) and their copolymers, demonstrative of excellent universality. The structurally optimized mPPy-nb exhibits high specific surface area of 122 m^(2) g^(−1)and large capacitance of 225 F g^(−1) at 1 mV s^(−1). Furthermore, the MSCs assembled by mPPy-nbs deliver impressive volumetric capacitance of 90 F cm^(−3) and energy density of 2.0 mWh cm^(−3), superior to the most reported polymers-based MSCs. Also, the fabricated MSCs present excellent flexibility with almost no capacitance decay under varying bending states, and robust serial/parallel self-integration for boosting voltage and capacitance output. Therefore, this work will inspire the new design of mesoporous conducting polymer materials toward high-performance microscale supercapacitive devices.

关键词： Interface co-assembly Dual-colloids mesopore Hollow nano-bowl Micro-supercapacitors

Bioactive glass nanotube scaffold with well-ordered mesoporous structure for improved bioactivity and controlled drug delivery

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Journal of Materials Science & Technology 2019年第9期35卷 1959-1965页

作者： Jian Xiao Yizao Wan Zhiwei Yang Yuan Huang Fanglian Yao Honglin Luo School of Materials Science and Engineering Tianjin UniversityTianjin300072China Institute of Advanced Materials School of Materials Science and EngineeringEast China Jiaotong UniversityNanchang330013China Key Laboratory of Systems Bioengineering of Ministry o f Education School o f Chemical Engineering and TechnologyTianjin UniversityTianjin300072 China

In this study, a novel mesoporous bioactive glass nanotube (MBGN) scaffold has been fabricated via template-assisted sol-gel method using bacterial cellulose (BC) as template and nonionic block copolymer (PI23) as pore-directing agent. The scaffold was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, and N2 adsorption-desorption analysis. Furthermore, simvastatin was used to evaluate the loading efficiency and release kinetics of the scaffold. The obtained scaffold displays nanofiber-like morphology, ordered mesopores on the tube walls, and interconnected three-dimensional (3D) network structure that completely replicates the BC template. In addition, it shows dual pore sizes (16.2 and 3.3 nm), large specific surface area (537.2 m^2 g^-1) and pore volume (1.429 cm^3 g^-1). More importantly, the scaffold possesses excellent apatite-forming ability and sustainable drug release as compared to the counterpart scaffold without mesopores. This unique scaffold can be considered a promising candidate for drug delivery and bone tissue regeneration.

关键词： Bioactive glass mesopore Nanotube Bioactivity Drug delivery

Pretreatment of Cylindrical Coconut Activated Carbon and Performance as Catalyst Support

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Chemical Research in Chinese Universities 2013年第5期29卷 941-946页

作者： PAN Chong-gen YE Lin-qin WANG Ju-hua BAO Li-xia QUE Yong-sheng National Center for International Research Zhejiang University Hangzhou 310058 P. R. China

Cylindrical coconut activated carbon（CCAC） support was graphitized at a high temperature（1900 ℃） in argon, then oxidized with an O2-N2-H2O mixture, and treated with nitric acid. Pretreatment of carbon support on its mechanical strength, physical structure, chemical composition and surface properties of cylindrical CCAC support was investigated by X-ray diffraction（XRD）, surface area analysis, scanning electron microscopy（SEM）, energy dis- persive spectroscopy（EDS）, thermogravimetric-differential thermogravimetric（TG-DTG） analysis and temperature programmed desorption-mass spectrometry（TPD-MS）, and the effect of CCAC support on the catalytic activities was also studied. The results show that the degree of graphitization, the purity（phosphorus, sulphur）, pore struc- ture（micropore, mesopore） and oxygen-containing functional groups（--COOH, --OH, --COOR） of carbon supports are obviously different, which have a great influence on the performance of Ru-based catalysts. After a series of pre- treatments, the surface physical and chemical properties of the commercial CCAC are modified and improved, and the activity of as-prepared Ru/AC catalyst is increased significantly.

关键词： Cylindrical coconut activated carbon（CCAC） Thermal treatment mesopore Catalyst

The effect of swelling agent on the pore characteristics of mesoporous hydroxyapatite nanoparticles

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Progress in Natural Science:Materials International 2015年第3期25卷 185-190页

作者： L.Bakhtiari J.Javadpour H.R.Rezaie M.Erfan M.A.Shokrgozar School of Metallurgical and Materials Engineering Iran University of Science and Technology School of Pharmacy Shahid Beheshti University of Medical Sciences National Cell Bank of Iran Pasteur Institute of Iran

The effect of swelling agent on the physicochemical properties of mesoporous hydroxyapatite particles synthesized by self-assembly process has been investigated. Cetyl trimethylammonium bromide(CTAB) and 1-dodecanethiol were used as soft template and swelling agent respectively. The results of the field emission scanning electron microscopy(FESEM), X-ray diffraction(XRD), simultaneous thermal analysis(STA), Brunauer-Emmett-Teller(BET) surface area, small-angle X-ray diffraction and Fourier transform infrared spectroscopy(FTIR)assessments revealed that in the case of low concentration, 1-dodecanethiol performed as swelling agent and caused an increase in the pore size. However, at higher concentrations it led to the formation of microemulsion and foamy structures. The optimum swelling agent: surfactant mass ratio in synthesis of mesoporous hydroxyapatite particles with high pore volume was determined to be around 2.1 in this study.

关键词： mesopore Hydroxyapatite Nanoparticle Swelling agent Pore characteristics

Large pore volume mesoporous aluminum oxide synthesized via nano-assembly

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Science China Chemistry 2009年第12期52卷 2114-2124页

作者： WANG DingCong Fushun Research Institute of Petroleum and Petrochemicals,China Petroleum and Chemical Corporation (SINOPEC),Fushun 113001,China Fushun Research Institute of Petroleum and Petrochemicals China Petroleum and Chemical Corporation (SINOPEC) Fushun China

A new nano-assembly approach has been proposed for the preparation of macropore volume mesoporous aluminum oxide supports. Secondary nano-assembly and a frame structure mechanism for large pore volume mesoporous supports have been proposed. In a primary nano-assembly supersoluble micelle,aluminum hydroxide nanoparticles were precipitated in situ in surfactants with a volume balance (VB) less than 1,followed by secondary nano-assembly in linear and cylindrical shapes. The secondary nano-assembly of cylindrical aluminum hydroxides was calcined to form nano cylindrical aluminum oxides. For the formation of macropore volume mesoporous supports,we utilized a frame structure mechanism of mesoporous support,in which the exterior surface of the carrier may not be continuous. This macropore volume support has been used for the hydrotreatment of a residual oil catalyst,which possesses the following physical characteristics:pore volume 1.8―2.7 mL·g-1,specific surface area 180―429 m2·g-1,average pore diameter 17―57 nm,average pore diameter more than 10 nm (81%―94%),porosity 87%―93%,and crush strength 7.7―25 N·mm-1.

关键词： pore volume mesopore aluminum oxide nano-assembly supersolubility pore size porosity