检索结果-南通市图书馆

Science China chemistry 2010年第8期53卷 1711-1717页

作者： jiang yaqi,li fangfang,sun ran,xie zhaoxiong & zheng lansun state key laboratory for physical chemistry of solid surfaces Department of chemistry,College of chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China 1. state key laboratory for physical chemistry of solid surfaces Department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

ZnO nanoparticles with different morphologies were solvothermally synthesized by controlling the alkali (sodium hydroxide) concentration in an isopropanol *** products were characterized by means of powder X-ray diffraction,UV-visible absorption spectra,scanning electron microscopy,transmission electron microscopy,and selected area electron *** morphologies of the formed ZnO nanocrystals were dependent on the concentration of the alkali,and with increases of sodium hydroxide concentration,the ZnO nanocrystals evolved from rod to hexagonal bipyramid,and then to a flower-like *** flower-like nanostructure resulted from the etching of the hexagonal bipyramid by the excess *** photoluminescence and photocatalytic properties of the prepared ZnO were *** difference of green emission among the ZnO nanocrystals indicated that a higher sodium hydroxide concentration led to a higher level of *** size,the surface structure and defects in the ZnO nanocrystals affected its photo-degradation characteristics.

关键词： zinc oxide solvothermal method nanocrystal photoluminescence photocatalysis

A facile surfactant-free synthesis of Rh flower-like nanostructures constructed from ultrathin nanosheets and their enhanced catalytic properties

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nano Research 2016年第3期9卷 849-856页

作者： yaqi jiang Jingyun Su Yanan Yang Yanyan Jia Qiaoli Chen zhaoxiong xie lansun zheng state key laboratory of physical chemistry of solid surfaces Collaborative Innovation Center of Chemistry for Energy Materials andDepartment of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

Rh is an important catalyst that is widely used in a variety of organic reactions. In recent years, many efforts have focused on improving its catalytic efficiency by fabricating catalyst nanoparticles with controlled size and morphology. However, the frequently employed synthesis route using organic compounds either as the reaction medium or capping agent often results in residual molecules on the catalyst surface, which in turn drastically diminishes the catalytic performance. Herein, we report a facile, aqueous, surfactant-free synthesis of a novel Rh flower- like structure obtained via hydrothermal reduction of Rh（acac）3 by formaldehyde. The unique Rh nanoflowers were constructed from ultrathin nanosheets, whose basal surfaces comprised {111} facets with an average thickness of -1.1 nm. The specific surface area measured by CO stripping was 79.3 m2-g-1, which was much larger than that of commercial Rh black. More importantly, the Rh nanoflower catalyst exhibited excellent catalytic performance in the catalytic hydrogenation of phenol and cyclohexene, in contrast to the commercial Rh black and polyvinyl pyrrolidone （PVP）-capped Rh nanosheets exposed by similar {111} basal surfaces.

关键词： rhodium nanocrystal nanosheet hydrogenation reaction

Advances in microwave absorbing materials with broad-bandwidth response

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2023年第8期16卷 11054-11083页

作者： Susu Bao Meixi Zhang Zhiyuan jiang zhaoxiong xie lansun zheng state key laboratory for physical chemistry of solid surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Microwave absorbing materials(MAMs)are playing an increasingly essential role in the development of wireless communications,high-power electronic devices,and advanced target detection *** with a broad-bandwidth response are particularly important in the area of communication security,radiation prevention,electronic reliability,and military *** considerable progress has been made in the design and preparation of MAMs with a broad-bandwidth response,a number of challenges still remain,and the structure–function relationship of MAMs is still far from being completely ***,the advances in the design and research of MAMs with a broad-bandwidth response are *** main strategies for expanding the effective absorption bandwidth of MAMs are comprehensively summarized considering three perspectives:the chemical combination strategy,morphological control strategy,and macrostructure control *** important results as well as design principles and absorption mechanisms are highlighted.A coherent explanation detailing the influence of the chemical composition and structure of various materials on the microwave absorption properties of MAMs is *** main challenges,new opportunities,and future perspectives in this promising field are also presented.

关键词： microwave absorbing materials broad-bandwidth response magnetic-dielectric synergy morphology control macrostructure control

A finite oxidation strategy for customizing heterogeneous interfaces to enhance magnetic loss ability and microwave absorption of Fe-cored carbon microcapsules

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2023年第8期16卷 11084-11095页

作者： Meixi Zhang Laisen Wang Susu Bao Zhijia Song Wenjiao Chen Zhiyuan jiang zhaoxiong xie lansun zheng state key laboratory for physical chemistry of solid surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China College of Materials Xiamen UniversityXiamen 361005China

Metallic iron particles are of great potential for microwave absorption materials due to their strong magnetic loss ***,the oxidation susceptibility of metallic iron particles in the atmospheric environment is regarded as a major factor causing performance *** many efforts have been developed to avoid their oxidation,whether partial surface oxidized iron particles can improve the microwave absorbing performance is rarely *** order to explore the effect of partial surface oxidation of iron on its properties,the designed yolk–shelled(Fe/FeO_(x))@C composites with multiple heterointerfaces were synthesized via an in-situ polymerization and a finite reduction–oxidation process of Fe_(2)O_(3)*** performance enhancement mechanisms of Fe/FeO_(x)heterointerfaces were also *** is demonstrated that the introduction of Fe-based heterogeneous interfaces can not only enhance the dielectric loss,but also increase the imaginary part of the permeability in the higher frequency range to strengthen the magnetic loss ***,the yolk–shell structure can effectively improve impedance matching and enhance microwave absorption performances via increasing multiple reflection and scattering behaviors of incident *** to Fe@C composite,the effective absorption(reflection loss(RL)lity and microwave absorption performance of Fe-based microwave absorption materials with promising practical applications.

关键词： heterogeneous interfaces finite oxidation yolk-shell structure magnetic loss interface polarization microwave absorption

A molten salt route to the synthesis of nano/micro-structured inorganic crystailites with all polar surfaces exposed

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A molten salt route to the synthesis of nano/micro-structure...

Surfactant dependent evolution of Au-Pd alloy nanocrystals from trisoctahedron to excavated rhombic dodecahedron and multipod： a matter of crystal growth kinetics

中国化学会第五届全国结构化学学术会议

作者： Tao Xu Xi Zhou Zhiyuan jiang zhaoxiong xie lansun zheng state key laboratory for physical chemistry of solid surfaces & Department of chemistry,Xiamen University,Xiamen 361005,Fujian,

＜正＞As has been well known,many ionic compounds can be described as a number of planes composed of cations and anions stacked *** positively-charged cations and negatively-charged anion planes give result to a normal dipole moment and spontaneous polarization along specific axis in these *** crystal growth,the polar surfaces

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Science Bulletin 2017年第20期62卷 1359-1364页

作者： Qiaoli Chen Guifen Du Yongdi Dong Zhenming Cao zhaoxiong xie lansun zheng state key laboratory of physical chemistry of solid surfaces Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen University Xiamen 361005 China

In wet chemical syntheses of noble metal nanocrystals,surfactants play crucial roles in regulating their *** date,more attention has been paid to the effect of the surfactant on the surface energy of crystal facets,while less attention has been paid to its effect on the growth *** this paper,using the growth of Au-Pd alloy nanocrystals as an example,we demonstrate that different concentration of surfactant hexadecyltrimethyl ammonium chloride(CTAC)may cause the different packing density of CTA+bilayers on different sites(face,edge or vertex)of crystallite surface,which would change the crystal growth kinetics and result in preferential crystal growth along the edge or vertex of *** unique shape evolution from trisoctahedron to excavated rhombic dodecahedron and multipod structure for Au-Pd alloy nanocrystals was successfully achieved by simply adjusting the concentration of *** results help to understand the effect of surfactants on the shape evolution of nanocrystals and open up avenues to the rational synthesis of nanocrystals with the thermodynamically unfavorable morphologies.

关键词： Au-Pd alloy Morphology Nanocrystal Surfactant

One-step synthesis of thermally stable artificial multienzyme cascade system for efficient enzymatic electrochemical detection

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nano Research 2019年第12期12卷 3031-3036页

作者： Xiqing Cheng Jinhong Zhou Jiayu Chen zhaoxiong xie Qin Kuang lansun zheng state key laboratory of physical chemistry of solid surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand Department of ChemistryCollege of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China

Recently,metal-organic framework(MOF)-based multienzyme systems integrating different functional natural enzymes and/or nanomaterial-basedartificial enzymes are attracting increasing attention due to their high catalytic efficiency and promising application in *** controllable integration of enzymes or nanozymes within MOFs is crucial for achieving efficient cascade catalysis and high ***,we report a facile electrochemical assisted biomimetic mineralization strategy to prepare an artificial multienzyme system for efficient electrochemicaldetection of *** using the G0x@Cu-MOF/copper foam(G0x@Cu-MOF/CF)architecture as a proof of concept,efficientenzyme immobilization and cascade catalysis were achieved by in situ encapsulation of glucose oxidase(GOx)within MOFs layer grown onthree-dimensional(3D)porous conducting CF via a facile one-step electrochemical assisted biomimetic mineralization *** to thebio-electrocatalytic cascade reaction mechanism,this well-designed GOx@Cu-MOF modified electrode exhibited superior catalytic activityand thermal stability for glucose ***,the activity of GOx@Cu-MOF/CF still remained at ca.80%after being incubated at 80℃.In sharp contrast,the activity of the unprotected electrode was reduced to the original 10%after the same *** design strategypresented here may be useful in fabricating highly stable enzyme@MOF composites applied for efficient photothermal therapy and otherplatform under high temperature.

关键词： metal-organic frameworks artificial multienzyme electrochemical assisted biomimetic mineralization glucose detection thermal stability

Origin of symmetry breaking in the seed-mediated growth of bi-metal nano-heterostructures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science Bulletin 2018年第14期63卷 892-899页

作者： Guifen Du Jun Pei Zhiyuan jiang Qiaoli Chen Zhenming Cao Qin Kuang zhaoxiong xie lansun zheng state key laboratory of physical chemistry of solid surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsDepartment of ChemistryCollege of Chemistry and Chemical EngineeringXiamen University Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen University

Seed-mediated growth is the most general way to controllably synthesize bimetal nano-heterostructures. Despite successful instances through trial and error were reported, the way for second metal depositing on the seed. namely whether the symmetry of resulted nano-heterostructure follows the original crystal symmetry of seed metal, remains an unpredictable issue to date. In this work, we propose that the ther- modynamic factor, i.e., the difference of equilibrium electrochemical potentials （corresponding to their Fermi levels） of two metals in the growth solution, plays a key role for the symmetry breaking of bimetal nano-heterostructures during the seed-mediated growth. As a proof-of-principle experiment, by revers- ing the relative position of Fermi levels of the Pd nanocube seeds and the second metal Au with changing the concentration of reductant （L-ascorbic acid） in the growth solution, the structure of as-prepared prod- ucts successfully evolved from centrosymmetric Pd@Au core-shell trisoctabedra to asymmetric Pd-Au hetero-dimers. The idea was further demonstrated by the growth of Ag on the Pd seeds. The present work intends to reveal the origin of symmetry breaking in the seed-mediated growth of nano-heterostructures from the viewpoint of thermodynamics, and these new insights will in turn help to achieve rational con- struction of bimetal nano-heterostructures with soecific functions.

关键词： Symmetry breaking Bimetal nano-heterostructures Seed-mediated growth Equilibrium electrochemical potentials

Novel hydrogen storage properties of palladium nanocrystals activated by a pentagonal cyclic twinned structure

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nano Research 2015年第8期8卷 2698-2705页

作者： Huang Huang Shixiong Bao Qiaoli Chen Yanan Yang Zhiyuan jiang Qin Kuang Xiaoyin Wu zhaoxiong xie lansun zheng state key laboratory of physical chemistry of solid surfaces Collaborative Innovation Center of Chemistry for Energy Materials andDepartment of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

Researchers appear to have neglected a special form of crystallites, pentagonal cyclic twinning, in which an obvious two-dimensional lattice expansion exists leading to novel physical-chemical properties associated with the changes in geometric and electronic structures. Using the storage and release of hydrogen in Pd nanocrystals as a probe, we have found that icosahedral pentagonal cyclic twinned Pd nanocrystals had distinct hydrogen storage properties, due to the two-dimensional lattice expansions, quite different from those of the octahedral single crystalline counterpart. In addition, the two-dimensional lattice expansion in pentagonal cyclic twinned Pd nanocrystals causes a change in electronic structure, which results in novel catalytic properties involving in situ formation of PdHx pentagonal cyclic twinned nanocrystals.

关键词： hydrogen storage lattice expansion tweed structure palladium nanoparticles

Solvent-dependent evolution of cyclic penta-twinned rhodium icosahedral nanocrystals and their enhanced catalytic properties

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2018年第2期11卷 656-664页

作者： Yanan Yang Jiawei Zhang Yajing Wei Qiaoli Chen Zhenming Cao Huiqi li Jiayu Chen Jueli Shi zhaoxiong xie lansun zheng state key laboratory for physical chemistry of solid surfaces Collaborative Innovation Center of Chemistry for Energy Materials Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen China

Cyclic penta-twinned noble metal nanocrystals exhibit promising properties due to their unique geometric and electronic structures. However, the controlled synthesis of cyclic penta-twinned nanostructures, especially of noble metals with a high cohesive energy （e.g., Rh）, is very difficult, and the corresponding growth mechanism is not fully understood. Herein, we report a facile one-pot hydrothermal approach for the synthesis of cyclic penta-twinned Rh icosahedral nanocrystals. It was found that apart from regulating the surface free energy by changing the concentration or category of the capping agents, the solvent might influence the adsorption ability of the surfactant on the Rh crystal surface, which results in a change in the surface free energy and thus allows the formation of Rh cyclic penta-twinned nanostructures. In addition, due to their unique electronic and geometric structures, the Rh icosahedral nanocrystals exhibit superior catalytic activity and stability for the electrooxidation of ethanol as compared to single-crystal Rh tetrahedral nanocrystals and commercial Rh black.

关键词： Rhrcrystal growth icosahedron tetrahedron electrocatalysis