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Melting Behaviour of Core-Shell Structured Ag-Rh Bimetallic Clusters

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Chinese Physics Letters 2007年第6期24卷 1656-1659页

作者：潘洋程道建黄世萍汪文川 division of Molecular and Materials Simulation Key Lab for Nanomaterials (Ministry of Education) Beijing University of Chemical Technology Beijing 100029

The melting behaviour of four typical core-shell structured 309-atom Ag-Rh bimetallic clusters, with decahedral and icosahedral geometric configurations, is investigated by using molecular dynamics simulation, based on the Sutton-Chen potential. The initial atomic configurations are obtained from semi-grand canonical ensemble Monte Carlo simulations. It is found that the melting point temperature Tm increases with the mole fraction of Rh in the bimetallic clusters, and Tm of Ag-Rh icosahedral clusters is higher than those of Ag-Rh decahedral clusters with the same Rh mole fraction. It is also found that the Ag atoms lie on the surface of Ag-Rh bimetallic clusters even after melting.

关键词： FINNIS-SINCLAIR POTENTIALS EMBEDDED-ATOM METHOD SURFACE SEGREGATION MONTE-CARLO CATALYTIC-ACTIVITY AG/AL2O3 CATALYST NANOPARTICLES ALLOYS PD ENERGETICS

Effect of particle size of calcium phosphate based bioceramic drug delivery carrier on the release kinetics of ciprofloxacin hydrochloride： an in vitro study

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Frontiers of Materials Science 2013年第3期7卷 261-268页

作者： Swamiappan SASIKUMAR Materials Chemistry division Centre for Excellence in Nanomaterials School of Advanced Sciences VIT University Vellore-632 014 Tamilnadu India

Hydroxyapatite （HAP） is the constituent of calcium phosphate based bone cement and it is extensively used as a bone substitute and drug delivery vehicle in various biomedical applications. In the present study we investigated the release kinetics of ciprofloxacin loaded HAP and analyzed its ability to function as a targeted and sustained release drug carrier, Synthesis of HAP was carried out by combustion method using tartaric acid as a fuel and nitric acid as an oxidizer. Powder XRD and FTIR techniques were employed to characterize the phase purity of the drug carrier and to verify the chemical interaction between the drug and carrier, The synthesized powders were sieve separated to make two different drug carriers with different particle sizes and the surface topography of the pellets of the drug carrier was imaged by AFM. Surface area and porosity of the drug carrier was carried out using surface area analyzer. The in-vitro drug release kinetics was performed in simulated body fuid, at 37.3℃. The amount of ciprofloxacin released is measured using UV-visible spectroscopy following the characteristic Amax of 278 nm. The release saturates around 450 h which indicates that it can be used as a targeted and sustained release carrier for bone infections.

关键词： ceramic drug delivery system antibiotic hydroxyapatite (HAP) porosity targeted release

Advances in bio-inspired electrocatalysts for clean energy future

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Nano Research 2024年第2期17卷 515-533页

作者： Jing-Wen Duan Mu Min-Rui Gao division of nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Electrocatalysis can enable efficient energy storage and conversion and thus is an effective way to achieve carbon *** unique structure and function of organisms can offer many ideas for the design of electrocatalysts,which has become one of the most promising research ***,the understanding of the mechanism of bio-inspired electrocatalysis has become clearer,which has promoted the design of bio-inspired catalysts and catalytic *** bio-inspired catalysts(enzyme-like catalysts,layered porous catalysts,superhydrophobic/superhydrophilic surfaces,and so on)have been developed to enable efficient electrocatalytic ***,we discuss the key advances in the field of bio-inspired electrocatalysts progressed in recent ***,the role of bio-inspiration in increasing the intrinsic activity and number of active sites of catalysts is ***,the structure and mechanism of layered porous catalytic systems that mimic biological transport systems are comprehensively ***,the design of three-phase interfaces from micro-nanoscale to atomic scale is highlighted,including the wettability of the electrode surface and the transport system near the *** conclude the review by identifying challenges in bio-inspired electrocatalysts and providing insights into future prospects for the exciting research field.

关键词： bio-inspired electrocatalysts active sites layered porous structure three-phase interface

Towards reliable assessment of hydrogen oxidation electrocatalysts for anion-exchange membrane fuel cells

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Nano Research 2023年第8期16卷 10787-10795页

作者： Fei-Yue Gao Ye-Hua Wang Yu Yang Jie Liao Jing-Wen DuanMu Xiao-Long Zhang Zhuang-Zhuang Niu Peng-Peng Yang Min-Rui Gao division of nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Recent advancement of proton exchange membrane fuel cells has led to commercial sales of fuel-cell cars but market barrier exists because this technology heavily relies on platinum *** the permission of adopting platinum-group-metal-free catalysts,anion-exchange membrane fuel cell has received notable ***,the sluggish kinetics of anodic hydrogen oxidation reaction(HOR)largely limit the cell *** many high-performance HOR catalysts have been reported,there are analytical uncertainties in the literature concerning the assessment of the catalyst *** we determine the origin of false HOR currents in the recorded polarization curves and propose a rigorous approach to eliminate *** unveil experimentally the uncertainties of obtaining exchange current densities(j0)using Tafel plot from Bulter–Volmer equation and recommend employing the micro-polarization region *** bulky catalysts that cannot establish a well-defined diffusion layer,we suggest applying external stirring bar to offer certain level of enforced convection and using j0 to compare the activity.

关键词： platinum group metal-free catalysts anion-exchange membrane fuel cell hydrogen oxidation reaction kinetic analysis

A reviving templating method for multiple nanostructures

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Science China Materials 2017年第5期60卷 461-462页

作者： Hui-Hui Li Shu-Hong Yu division of nanomaterials & Chemistry Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemistry University ofScience and Technology of China Hefei 230026 China

Binary materials,comprised by two dissimilar components in one matrix,already exist in nature from the subatomic to the universal scale with different kinds of forms(e.g.,nuclei and electrons,matter and antimatter)[1]... 详细信息

关键词：英语阅读理解材料科学

Pure and Mg-doped self-assembled ZnO nano-particles for the enhanced photocatalytic degradation of 4-chlorophenol

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Journal of Environmental Sciences 2013年第10期25卷 2157-2167页

作者： N.Clament Sagaya Selvam S.Narayanan L.John Kennedy J.Judith Vijaya Catalysis and nanomaterials Research Laboratory Department of Chemistry Loyola College Materials division School of Advanced Sciences Vellore Institute of Technology UniversityChennai Campus

A novel self-assembled pure and Mg doped ZnO nano-particles （NPs） were successfully synthesized by a simple low temperature co-precipitation method. The prepared photocatalysts were characterized by X-ray diffraction, high resolution scanning electron mi- croscopy, high resolution transmission electron microscopy, diffuse reflectance spectroscopy and photoluminescence （PL） spectroscopy. The results indicated that the prepared photocatalysts showed high crystallinity with a uniform size distribution of the NPs. The degradation of cholorphenols is highly mandatory in today＇s scenario as they are affecting the environment adversely. Thus, the photocatalytic degradation of 4-chlorophenol （4-CP）, a potent endocrine disrupting chemical in aqueous medium was investigated by both pure and Mg-doped ZnO NPs under UV-light irradiation in the present study. The influence of the Mg content on the structure, morphology, PL character and photocatalytic activity of ZnO NPs were investigated systematically. Furthermore,the effect of different parameters such as 4-CP concentration, photocatalyst amount, pH and UV-light wavelength on the resulting photocatalytic activity was investigated.

关键词： Mg-doped ZnO nanoparticles photocatalyst photocatalytic degradation 4-chlorophenol

Preventing structural aging with synthetic tooth enamel

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Science China Materials 2017年第7期60卷 683-684页

作者： Li-Bo Mao Huai-Ling Gao Shu-Hong Yu division of nanomaterials ＆ Chemistry Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemistry University of Science and Technology of China Hefei 230026 China

Teeth are typically non-regenerative and permanent skele- tal structures and their resilience to aging is one of the top requirements for the survival of the species. Recent investi- gations on mechanical properties of laboratory-made teeth enamel analogs show that they have a unique combination of stiffness, E, and vibration damping, tanδ .

关键词：英语阅读理解材料科学

Hydrazine-Cadmium Tellurite Hybrid Microcrystals: An Efficient Precursor to Porous Cadmium Telluride and Tellurium Architectures Through Its Thermal Decomposition

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Nano Research 2010年第2期3卷 81-91页

作者： Hong-Bin Yao Xiao-Bo Li Si-Yuan Ai Shu-Hong Yu division of nanomaterials and Chemistry Hefei National Laboratory for Physical Sciences at MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Well-defined platelet-like hydrazine-cadmium tellurite hybrid microcrystals have been synthesized by a solvothermal reaction of cadmium chloride,sodium tellurite,and hydrazine hydrate in a mixed solvent containing n-propylamine and deionized *** formula of the hybrid platelet-like microcrystals has been proposed based on a combination of powder X-ray diffraction pattern(PXRD),elemental analysis,thermogravimetic analysis(TGA),and X-ray photoelectron spectroscopy(XPS).Controlled thermal decomposition of this hybrid precursor can lead to the formation of porous platelet-like *** porous cadmium telluride architectures were obtained by using hydrochloric acid to dissolve CdTeO3 remaining in the sample after thermal decomposition at 450°*** addition,unique nanoporous tellurium architectures were obtained by using hydrochloric acid to dissolve the amorphous Cd(N2H4)TeO3 formed after thermal decomposition at 300°C,followed by an in situ topotactic reaction between the residual three-dimensional(3-D)skeleton of cadmium telluride nanocrystallites and−***-Emmett-Teller(BET)analysis and a study of the optical properties of these porous cadmium telluride and tellurium materials have also been carried out.

关键词： Thermal decomposition hydrazine hybrid porous architecture tellurium

Fast Zn^(2+)mobility enabled by sucrose modified Zn^(2+)solvation structure for dendrite-free aqueous zinc battery

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Nano Research 2023年第3期16卷 3839-3846页

作者： Yufang Cao Xiaohui Tang Linge Li Haifeng Tu Yuzhen Hu Yingying Yu Shuang Cheng Hongzhen Lin Liwen Zhang Jiangtao Di Yongyi Zhang Meinan Liu School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026China Key Laboratory of Multifunctional nanomaterials and Smart Systems Advanced Materials DivisionSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China division of nanomaterials and Jiangxi Key Lab of Carbonene Materials Jiangxi Institute of NanotechnologyNanchang 330200China

Aqueous zinc battery has been regarded as one of the most promising energy storage systems due to its low cost and environmental ***,the safety concern on Zn anodes caused by uncontrolled Zn dendrite growth in aqueous electrolyte hinders their ***,sucrose with multi-hydroxyl groups has been introduced into aqueous electrolyte to modify Zn^(2+)solvation environment and create a protection layer on Zn anode,thus effectively retarding the growth of zinc *** simulations and experiments confirm that sucrose molecules can enter into the solvation sheath of Zn^(2+),and the as-formed unique solvation structure enhances the mobility of Zn^(2+).Such fast Zn^(2+)kinetics in sucrose-modified electrolyte can successfully suppress the dendrite *** this sucrose-modified aqueous electrolyte,Zn/Zn symmetric cells present more stable cycle performance than those using pure aqueous electrolyte;Zn/C cells also deliver an impressive higher energy density of 129.7 Wh·kg^(−1)and improved stability,suggesting a great potential application of sucrose-modified electrolytes for future Zn batteries.

关键词： solvation structure Zn^(2+)mobility dendrite suppression sucrose