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Hydrothermal Synthesis of Nanostructured Vanadium Oxides  [PDF]
Jacques Livage
Materials , 2010, DOI: 10.3390/ma3084175
Abstract: A wide range of vanadium oxides have been obtained via the hydrothermal treatment of aqueous V(V) solutions. They exhibit a large variety of nanostructures ranging from molecular clusters to 1D and 2D layered compounds. Nanotubes are obtained via a self-rolling process while amazing morphologies such as nano-spheres, nano-flowers and even nano-urchins are formed via the self-assembling of nano-particles. This paper provides some correlation between the molecular structure of precursors in the solution and the nanostructure of the solid phases obtained by hydrothermal treatment.
A Comprehensive Review of Glucose Biosensors Based on Nanostructured Metal-Oxides  [PDF]
Md. Mahbubur Rahman,A. J. Saleh Ahammad,Joon-Hyung Jin,Sang Jung Ahn,Jae-Joon Lee
Sensors , 2010, DOI: 10.3390/s100504855
Abstract: Nanotechnology has opened new and exhilarating opportunities for exploring glucose biosensing applications of the newly prepared nanostructured materials. Nanostructured metal-oxides have been extensively explored to develop biosensors with high sensitivity, fast response times, and stability for the determination of glucose by electrochemical oxidation. This article concentrates mainly on the development of different nanostructured metal-oxide [such as ZnO, Cu(I)/(II) oxides, MnO2, TiO2, CeO2, SiO2, ZrO2, and other metal-oxides] based glucose biosensors. Additionally, we devote our attention to the operating principles (i.e., potentiometric, amperometric, impedimetric and conductometric) of these nanostructured metal-oxide based glucose sensors. Finally, this review concludes with a personal prospective and some challenges of these nanoscaled sensors.
Nanostructured Mesoporous Silicas for Bone Tissue Regeneration  [PDF]
Isabel Izquierdo-Barba,Montserrat Colilla,María Vallet-Regí
Journal of Nanomaterials , 2008, DOI: 10.1155/2008/106970
Abstract: The research on the development of new biomaterials that promote bone tissue regeneration is receiving great interest by the biomedical scientific community. Recent advances in nanotechnology have allowed the design of materials with nanostructure similar to that of natural bone. These materials can promote new bone formation by inducing the formation of nanocrystalline apatites analogous to the mineral phase of natural bone onto their surfaces, i.e. they are bioactive. They also stimulate osteoblast proliferation and differentiation and, therefore, accelerate the healing processes. Silica-based ordered mesoporous materials are excellent candidates to be used as third generation bioceramics that enable the adsorption and local control release of biological active agents that promote bone regeneration. This local delivery capability together with the bioactive behavior of mesoporous silicas opens up promising expectations in the bioclinical field. In this review, the last advances in nanochemistry aimed at designing and tailoring the chemical and textural properties of mesoporous silicas for biomedical applications are described. The recent developed strategies to synthesize bioactive glasses with ordered mesopore arrangements are also summarized. Finally, a deep discussion about the influence of the textural parameters and organic modification of mesoporous silicas on molecules adsorption and controlled release is performed.
Catalytic Behaviour of Mesoporous Cobalt-Aluminum Oxides for CO Oxidation  [PDF]
Ankur Bordoloi,Miguel Sanchez,Heshmat Noei,Stefan Kaluza,Dennis Gro?mann,Yuemin Wang,Wolfgang Grünert,Martin Muhler
Journal of Catalysts , 2014, DOI: 10.1155/2014/807545
Abstract: Ordered mesoporous materials are promising catalyst supports due to their uniform pore size distribution, high specific surface area and pore volume, tunable pore sizes, and long-range ordering of the pore packing. The evaporation-induced self-assembly (EISA) process was applied to synthesize mesoporous mixed oxides, which consist of cobalt ions highly dispersed in an alumina matrix. The characterization of the mesoporous mixed cobalt-aluminum oxides with cobalt loadings in the range from 5 to 15?wt% and calcination temperatures of 673, 973, and 1073?K indicates that Co2+ is homogeneously distributed in the mesoporous alumina matrix. As a function of the Co loading, different phases are present comprising poorly crystalline alumina and mixed cobalt aluminum oxides of the spinel type. The mixed cobalt-aluminum oxides were applied as catalysts in CO oxidation and turned out to be highly active. 1. Introduction Supported metal oxide catalysts have attracted much attention in recent years due to their widespread applicability in industrially and academically important reactions. The extent and nature of the interaction, dispersion, and reducibility of the metal oxides depend on the synthesis method, loading, calcination temperature, and time. Cobalt supported on alumina is a typical catalyst, which is specially important for Fischer-Tropsch synthesis. Conventionally, the preparation of cobalt catalysts is performed by incipient wetness impregnation using suitable cobalt precursors on commercial alumina at low pH. Weak interaction is normally observed between the positively charged alumina carrier and the cobalt cations resulting in relatively large crystallite sizes [1–4]. Continuous efforts have been made in the last few decades by several groups [5–7] to synthesize porous alumina with high surface area by high-temperature dehydration of bulk powders [8], modified sol-gel synthesis in the presence of organic moieties [9, 10], different surfactants [3], block copolymers [11–14], or evaporation-induced self-assembly (EISA) with colloidal precursors and amine structural agents [15, 16]. These materials represent an active support, which may participate positively or negatively in the formation of the final catalysts. Moreover, the methods of hard templating [17] (carbon template) and microwave irradiation [18] in the presence of surfactants have been applied to synthesize alumina materials with crystalline, ordered, and uniform mesopores. However, this process is very time consuming and hardly scalable for industrial applications. Ordered mesoporous materials
Electrochemical Fabrication and Electrocatalytic Properties of Nanostructured Mesoporous Platinum Microelectrodes
Mengyan NIE,Joanne MElliott,
Mengyan NIE
,Joanne M.Elliott

材料科学技术学报 , 2005,
Abstract: Electrodeposition from a lyotropic liquid crystal template medium was used to produce nanostructured platinum microelectrodes with high specific surface area and high mass transport efficiency. Compared to polished and conventional platinized microelectrodes, well-ordered nanostructured platinum microelectrodes exhibited enhanced electrocatalytic properties for oxygen and ascorbic acid, whilst well-ordered nanostructured platinum microelectrodes offered improved electrocatalytic properties for oxygen reduction compared to disordered nanostructured platinum microelectrodes.
Preparation, Characterization and Application of Hollow Microspheres Assembled with Nanocrystals of Iron Oxides
CAO Shao-Wen, ZHU Ying-Jie, WANG Ke-Wei, CHEN Feng, CHENG Guo-Feng, HUANG Yue-Hong
无机材料学报 , 2011, DOI: 10.3724/sp.j.1077.2011.00458
Abstract: Nanostructured hollow microspheres of iron oxides are promising for the applications in the fields of magnetic storage media, catalysis, pigments, adsorbents, biomedicine, sensors, etc., due to their low toxicity, excellent magnetic properties, chemical stability, biocompatibility, corrosion resistance, low density and high specific surface area. The investigation on hollow microspheres assembled with nanocrystals of iron oxides is of especially scientific interest and technological importance. Herein, we briefly review several novel methods that have been developed in recent years for the preparation of nanostructured hollow microspheres of iron oxides constructed by self―assembly with different building blocks, sizes and hollow interiors. And the potential applications of the as―prepared iron oxide hollow microspheres in the fields of drug delivery, adsorption and photocatalysis are also discussed.
Synthesis of Ce3+-Doped Terbium Aluminum Garnet Phosphors from Nanostructured Oxides  [cached]
Dotsenko V.P.,Zubar E.V.,Berezovskaya I.V.,Poletaev N.I.
Proceedings of the International Conference Nanomaterials : Applications and Properties , 2012,
Abstract: The paper describes the synthesis of Ce3+-doped terbium aluminum garnet (TAG) phosphors with the use of nanostructured oxides of aluminum and rare earths. Aluminum oxide nanoparticles were obtained by gaseous-disperse synthesis and characterized by X-ray diffraction, differential thermal analysis and scanning electron microscopy. The preparation of cerium-doped terbium oxide nanopowders and luminescent properties of the Тb3(1-x)Ce3xAl5O12 phosphors are also discussed.
Reaction Mechanism and Control of Selectivity in Catalysis by Oxides: Some Challenges and Open Questions  [PDF]
Gabriele Centi,Siglinda Perathoner
International Journal of Molecular Sciences , 2001, DOI: 10.3390/i2050183
Abstract: Some aspects of the reaction mechanisms in multistep selective (amm)oxidation reactions over oxide surfaces are discussed evidencing some of the challenges for surface science and theory in describing these reactions, and for applied catalysis in order to have a more in deep identification of the key factors governing surface reactivity and which may be used to improve catalytic performances. In particular, the role of chemisorbed species in the modification of the surface reactivity and the presence of multiple pathways of reaction are evidenced by comparing the behavior of V-based catalysts in C3-C4 alkanes and alkene oxidation.
Gas Sensors Based on One Dimensional Nanostructured Metal-Oxides: A Review  [PDF]
M. M. Arafat,B. Dinan,Sheikh A. Akbar,A. S. M. A. Haseeb
Sensors , 2012, DOI: 10.3390/s120607207
Abstract: Recently one dimensional (1-D) nanostructured metal-oxides have attracted much attention because of their potential applications in gas sensors. 1-D nanostructured metal-oxides provide high surface to volume ratio, while maintaining good chemical and thermal stabilities with minimal power consumption and low weight. In recent years, various processing routes have been developed for the synthesis of 1-D nanostructured metal-oxides such as hydrothermal, ultrasonic irradiation, electrospinning, anodization, sol-gel, molten-salt, carbothermal reduction, solid-state chemical reaction, thermal evaporation, vapor-phase transport, aerosol, RF sputtering, molecular beam epitaxy, chemical vapor deposition, gas-phase assisted nanocarving, UV lithography and dry plasma etching. A variety of sensor fabrication processing routes have also been developed. Depending on the materials, morphology and fabrication process the performance of the sensor towards a specific gas shows a varying degree of success. This article reviews and evaluates the performance of 1-D nanostructured metal-oxide gas sensors based on ZnO, SnO2, TiO2, In2O3, WOx, AgVO3, CdO, MoO3, CuO, TeO2 and Fe2O3. Advantages and disadvantages of each sensor are summarized, along with the associated sensing mechanism. Finally, the article concludes with some future directions of research.
Mixed Nanostructured Ti-W Oxides Films for Efficient Electrochromic Windows
Nguyen Nang Dinh,Dang Hai Ninh,Tran Thi Thao,Truong Vo-Van
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/781236
Abstract: With the aim to enhance the electrochromic (EC) efficiency and electrochemical stability of electrochromic devices (ECD), mixed nanostructured TiO2/WO3 films were prepared by an electrochemical deposition method with the purpose of adding WO3 nanoparticles to porous nanocrystalline doctor-blade TiO2 (nc-TiO2) films. The results of the characterization of electrochromic properties in 1 M LiClO4
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