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Rare Metals 2023年第6期42卷 1800-1807页

作者： Si-Jia Zheng Hua Cheng Jin Yu Qin Bie Jing-Dong Chen Feng Wang Rui Wu Daniel John Blackwood Jun-Song Chen Gathering and Transmission Technology Research Institute of Southwest Oil and Gas Field Company of CNPC Chengdu610000China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu611731China Department of Materials Science and Engineering National University of SingaporeSingapore117574Singapore

Electrocatalytic reduction of carbon dioxide(CO_(2)RR) into high value-added chemicals and fuels has been regarded as a promising approach to achieve carbon neutrality.Though nickel-nitrogen-carbon(Ni-N-C) electrocatalysts have shown superior CO_(2)RR performance,the synthesis of highly effective Ni-N-C catalyst is still challenging.Herein,a three-dimensional(3D) ordered porous nitrogendoped carbon-supported Ni-N_(x) catalyst has been synthesized by direct pyrolysis of a mixture of SiO_(2),polyvinyl pyrrolidone,nickel-phenanthroline complex,followed by the removal of the SiO_(2) templates.

关键词： ordered porous nickel

Synthesis of ordered hierarchically mesoporous/microporous carbon materials via compressed CO_(2) for fructose-to-HMF transformation

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Green Energy & Environment 2022年第5期7卷 1033-1044页

作者： Sen Luan Wei Li Zanwu Guo Wenxiu Li Xiaojian Hou Yi Song Ran Wang Qian Wang Department of Chemistry Capital Normal UniversityBeijing100048China

Well-ordered hierarchically mesoporous/microporous carbon materials have been successfully fabricated by using dual soft-templating approach through compressed CO_(2).Pluronic F127 and different type of surfactants,including nonionic,cationic,and anionic surfactants,were used as dual templates to investigate the influence on the morphology and nanostructure of the as-prepared carbon samples.TEM,SEM,N2 sorption,wide-angle and small-angle XRD analysis were employed to reveal the well-ordered hierarchically micro-mesoporous structure with2 D hexagonal symmetry by using compressed CO_(2).The prepared HPC samples with different pressures as the catalyst carriers have been functioned by chlorosulfonic acid for the fructose conversion into HMF.Chlorosulfonic acid concentration,catalyst dosage and reaction temperature have been optimized for fructose-to-HMF transformation with the obtained catalyst.The performances of as-made HPC-SO_(3) H samples in HMF yield and reaction rate of fructose-to-HMF transformation have been investigated.The stability of the samples was also conducted in the dehydration of fructose to HMF for five cycles.The possible catalytic mechanism by using hierarchically porous carbon materials as catalyst support for fructose-to-HMF transformation was proposed.

关键词： ordered catalyst carbon

Hierarchical highly ordered SnO_(2) nanobowl branched ZnO nanowires for ultrasensitive and selective hydrogen sulfide gas sensing

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Microsystems & Nanoengineering 2020年第1期6卷 1016-1028页

作者： Li-Yuan Zhu Kai-Ping Yuan Jia-He Yang Cheng-Zhou Hang Hong-Ping Ma Xin-Ming Ji Anjana Devi Hong-Liang Lu David Wei Zhang State Key Laboratory of ASIC and System Shanghai Institute of Intelligent Electronics&SystemsSchool of MicroelectronicsFudan University200433 ShanghaiChina Inorganic Materials Chemistry Ruhr-University Bochum44780 BochumGermany

Highly sensitive and selective hydrogen sulfide(H_(2)S)sensors based on hierarchical highly ordered SnO_(2) nanobowl branched ZnO nanowires(NWs)were synthesized via a sequential process combining hard template processing,atomic-layer deposition,and hydrothermal processing.The hierarchical sensing materials were prepared in situ on microelectromechanical systems,which are expected to achieve high-performance gas sensors with superior sensitivity,long-term stability and repeatability,as well as low power consumption.Specifically,the hierarchical nanobowl SnO_(2)@ZnO NW sensor displayed a high sensitivity of 6.24,a fast response and recovery speed(i.e.,14 s and 39 s,respectively),and an excellent selectivity when detecting 1 ppm H_(2)S at 250°C,whose rate of resistance change(i.e.,5.24)is 2.6 times higher than that of the pristine SnO_(2) nanobowl sensor.The improved sensing performance could be attributed to the increased specific surface area,the formation of heterojunctions and homojunctions,as well as the additional reaction between ZnO and H_(2)S,which were confirmed by electrochemical characterization and band alignment analysis.Moreover,the well-structured hierarchical sensors maintained stable performance after a month,suggesting excellent stability and repeatability.In summary,such well-designed hierarchical highly ordered nanobowl SnO_(2)@ZnO NW gas sensors demonstrate favorable potential for enhanced sensitive and selective H_(2)S detection with long-term stability and repeatability.

关键词： nanowires ordered sulfide

Adsorptive removal of resorcinol on a novel ordered mesoporous carbon(OMC) employing COK-19 silica scaffold:Kinetics and equilibrium study

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Journal of Environmental Sciences 2019年第1期31卷 307-317页

作者： Zaki Uddin Ahmad Qiyu Lian Mark E.Zappi Prashanth R.Buchireddy Daniel Dianchen Gang Department of Civil Engineering University of Louisiana at Lafayette Center for Environmental Technology The Energy Institute of Louisiana Department of Chemical Engineering University of Louisiana at Lafayette

Phenolic compounds and their derivatives have been found in industrial wastewater, which pose threats to the natural environment. ordered mesoporous carbon(OMC) has been identified as an ideal adsorbent possessing high specific surface area and large pore volume to alleviate these pollutants. A novel ordered mesoporous carbon was prepared using COK-19 template with the cubic Fm3 m structure for the first time. ordered mesoporous silica COK-19 was synthesized and reported in 2015. Sucrose as the carbon precursor was impregnated into the mesopores of silica and converted to carbon through carbonization process using sulfuric acid as a catalyst. ordered mesoporous carbon was obtained after the removal of silica framework using hydrofluoric acid. Boric acid was employed for the preparation of OMCs with tunable pore sizes in the range of 6.9–16.6 nm. Several characterization techniques such as nitrogen adsorption–desorption isotherms, transmission electron microscope(TEM), Fourier transform infrared spectroscopy, Boehm titration and elemental analysis were employed to characterize the OMCs. The pore size analysis and TEM images confirmed that OMC has replicated the mesostructure of the COK-19. Results obtained from adsorption kinetics and isotherms suggest that the Pseudo-second-order model and Langmuir isotherm well described the experimental data.

关键词： ordered mesoporous carbon COK-19 TEM image Resorcinol Adsorption isotherm Adsorption kinetics

Perfect short-range ordered alloy with line-compound-like properties in the ZnSnN_(2):ZnO system

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npj Computational Materials 2020年第1期6卷 1132-1137页

作者： Jie Pan Jacob J.Cordell Garritt J.Tucker Andriy Zakutayev Adele C.Tamboli Stephan Lany Materials Science Center National Renewable Energy LaboratoryGoldenCO 80401USA Department of Mechanical Engineering Colorado School of MinesGoldenCO 80401USA

We present a new solid-state material phase which is a disordered solid solution but offers many ordered line-compound features.The emergent physical phenomena are rooted in the perfect short-range order which conserves the local octet rule.We model the dual-sublattice-mixed semiconductor alloy (ZnSnN_(2))_(1-x)(ZnO)_(2x) using first-principles calculations,Monte-Carlo simulations with a model Hamiltonian,and an extension of the regular solution model by incorporating short-range order.

关键词： alloy ordered compound

Comprehensive impact of as-cast microstructure and ordered structures on formability of large-scale Fe-6.5 wt.%Si alloy ingots

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Journal of Iron and Steel Research(International) 2020年第2期27卷 180-187页

作者： Xiang-ju Shi Yong-feng Liang Shi-bo Wen Zhi-yi Ding Bao Zhang Wei Song Feng Ye State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Large-scale Fe-6.5 wt.%Si ingot with excellent formability is required for a pilot line producing sheets through hot/cold rolling.The variation of the as-cast microstructure,ordered structures and the formability of the Fe-6.5 wt.%Si alloy ingots with the cooling rate during casting was investigated.Under air-cooling condition,inhomogeneous microstructures with a low proportion of equiaxed grains were formed,but the formation of ordered structures was partially inhibited,especially DO3.Homogeneous microstructures with a high proportion of equiaxed grains were observed under the condition of furnace cooling,but the ordered structures were fully generated,and the degree of order is high.It is generally believed that high degree of order is the main factor of brittleness,but the homogeneous microstructure(including grain morphology and size)of the furnace-cooled sample helps to improve the formability.The influence of these two aspects on formability is contradictory.Therefore,the formability is tested through the flow stress during the compression and the microstructure after the compression.The results show that the furnace-cooled sample has better formability.For large-scale ingots,the control of as-cast microstructure becomes more significant than the control of degree of order.Slow cooling during casting is important for the large-scale ingots to have good formability meeting the requirements of direct hot rolling.

关键词： Large-scale ingot Fe-6.5 wt.%Si alloy Cooling method Formability ordered structure As-cast microstructure

Structural Transition from ordered to Disordered of BeZnO2 Alloy

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Chinese Physics Letters 2020年第5期37卷 81-84页

作者：秦丽霞梁汉普蒋荣立 School of Materials and Physics China University of Mining and TechnologyXuzhou 221116 School of Chemical Engineering China University of Mining and TechnologyXuzhou 221116

Employing Monte Carlo simulations based on the cluster expansion,the special quasi-random structures and first-principles calculations,we systematically investigate the structure transition of BeZnO2 alloys from the ordered to the disordered phase driven by the increased synthesis temperature,together with the solid-state phase diagram.It is found that by controlling the ordering parameter at the mixed sublattice,the band structure can vary continuously from a wide direct band gap of 4.61 eV for the fully ordered structure to a relatively narrow direct band gap of 3.60 eV for the fully disordered structure.Therefore,a better optical performance could be achieved simply by controlling the synthesis temperature,which determines the ordering parameters and thus the band gaps.

关键词： structure. BeZnO ordered

N-doped ordered mesoporous carbon spheres derived by confined pyrolysis for high supercapacitor performance

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Journal of Materials Science & Technology 2019年第10期35卷 2178-2186页

作者： Juan Du Lei Liu Yifeng Yu Yue Zhang Haijun Lv Aibing Chen College of Chemical and Pharmaceutical Engineering Hebei University of Science and Technology

Herein, we report a confined pyrolysis strategy to prepare mesoporous carbon nanospheres by which surface area of carbon spheres is increased, pore size is enlarged and effective N-doping is achieved. In this method, the mesoporous polymer sphere as carbon precursor and 2-methylimidazole as nitrogen precursor are encapsulated in a compact silica shell which provides a confined nano-space for the pyrolysis treatment. The in situ generated gases from mesoporous polymer sphere and 2-methylimidazole under pyrolysis diffuse into the pores of mesoporous polymer sphere in the confined compact silica shell,resulting in increased surface area, larger pore size and N-doping due to self-activation effect. As electrodes in supercapacitor, the N-doped mesoporous carbon nanospheres exhibit a significantly enhanced specific capacitance of 326 Fg^-1 at 0.5 Ag^-1, which is 2 times higher than that of mesoporous carbon spheres under unconfined pyrolysis condition, exhibiting its potential for electrode materials with high performance.

关键词： Confined pyrolysis N-doping ordered large mesoporous spheres Supercapacitor

M2M’AlB4（M = Mn, Fe, Co, M’ = Cr, Mo, W）: Theoretical predicted ordered MAB phases with Cr3AlB4 crystal structure

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Journal of Materials Science & Technology 2019年第7期35卷 1432-1438页

作者： Fu-Zhi Dai Huimin Xiang Yinjie Sun Yanchun Zhou Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials & Processing Technology

The nanolaminated MAB phases have attracted great research interests due to their unusual combination of metal-like and ceramic-like properties, which is similar to MAX phases. Recently, ordered quaternary MAX phases have been discovered, which enriches the family of MAX phases, and opens a new window to tailor the properties of MAX phases and to develop new MXenes. In the present work, we explored possible ordered quaternary MAB phases with Cr3AlB4 structure(space group: Pmmm) by first-principles calculations. The predictions show that M2M’AlB4 phases with M = Mn, Fe, Co and M’ = Cr, Mo, W exhibit strong tendency of ordering, where M locates at 2t site(0.5, 0.5, z2t) and M’ locates at 1 g site(0, 0.5,0.5). The main driving force of ordering may be the differences in bonding strengths between Al and M elements. Analyses on chemical bonds reveal that bonding strengths increase following the order:Al-Mn ordered M2M’AlB4 phases with M =Mn or Fe are predicted ferromagnetic and ordered M2M’AlB4 phases display lower shear resistance and possibly better ductility in comparison to Cr3AlB4.

关键词： MAB phase ordered structure First-principle calculations Cr3AlB4 Chemical bonds Ultrahigh temperature ceramics

ordered Organization of Long Chain Polymers:Advances and Challenges

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Chinese Journal of Polymer Science 2022年第6期40卷 543-543页

作者： Quan Chen Shou-Ke Yan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Beijing China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing China

Due to the long chain character and entanglement feature,polymer chains were initially believed incapable of organizing into ordered structures.However,X-ray studies in the 1920s demonstrated unequivocally the existen... 详细信息

关键词： ordered polymer initially