سال انتشار: ۱۳۸۷

محل انتشار: دومین کنگره بین المللی علوم و فناوری نانو

تعداد صفحات: ۳

نویسنده(ها):

R Ghasempour – Institute for Nanoscience and Nanotechnology, Sharif University of Technology
A Iraji zad –
S Fardin doutst – Department of Physic, Sharif University of Technology, P .O. Box: 11155-9161, Teharn
N Taghavi nia – Department of Physic, Sharif University of Technology, P .O. Box: 11155-9161, Teharn

چکیده:

WO3 is a wide band gap n-type semiconductor material which has received a large amount of attention due to various applications such as gas sensors, electrochromic property, photocatalytic application and photochromic behavior [1-3]. Several methods including chemical vapour deposition (CVD), sol gel, magnetron sputtering, vacuum evaporation and plasma enhanced chemical vapour deposition (PECVD) have been used to prepare WO3 nanoparticles and thin films[2]. Among them sol gel, the peroxopolytungstic acid method (P-PTA) which was developed by kudo has many advantages such as high homogeneity, long term stable sol, low processing temperature which is important for making organic/inorganic hybrids[3]. On the other hand, CNTs are one of nanostructure materials with high surface to volume aspect ratio, and individual physical and chemical properties. Agglomeration of CNTs into bundle during synthesis process appears a technological difficulty when the well dispersed CNTs in solution were needed. To overcome this difficulty, modification of chemical composition of carbon nanotubes surface has proved to be efficient. Several methods such as chemical functionalisation, electrochemical, fluorination, polymer wrapping, mechano-chemical treatment and plasma treatment have been applied [4]. By grafting suitable nanostructure and chemical groups on the inert sidewall of CNT, surface fanctionalisation increased the hydrophilic character of CNTs. This property can improve their dispersion through the matrix of organic and inorganic solution. Also their electrical, elecrtonical, effective surface area and chemical reactivity of CNTs can be changed [4, 5]. For interaction between nanostructure material and surface of CNTs defects have important role. Thus, introducing and controlling density of defects can be used to tune the interfacial property of nanostructure materials. These properties will be determined with their size and dispersion [6]. The WO3-CNTs hybrid structure is suitable for gas sensing application. In this work, we prepare MWNTs and WO3 nanoparticles as a hybrid material. Tungsten trioxide nanoparticles have been prepared using P-PTA as a precursor. Various characterization methods were applied to analyze structure of the Functionalized MWNTs and hybrid.