Electrical Characterization of Polyaniline-ZnO nano-composite Langmuir-Blodgett thin films by Conductive Atomic Force Mi
- PDF / 988,653 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 118 Downloads / 230 Views
Electrical Characterization of Polyaniline-ZnO nano-composite Langmuir-Blodgett thin films by Conductive Atomic Force Microscopy Gurpreet Kaur Bhullar, Ramneek Kaur and K. K. Raina Materials Research Laboratory, School of Physics and Materials Science, Thapar University, Patiala-147004, India ABSTRACT Polyaniline–Zinc oxide nano-composite material was prepared by chemical polymerization of aniline with ZnO nano-particles doping. Surface Pressure-Area (π-A) isotherms of Polyaniline (PANi) and Polyaniline–Zinc oxide nano-composite shows phase transformations of monolayer during compression process. Multiple isotherms indicate that the monolayer of the composite material can retain its configuration during compression-expansion cycles. The structural, topographical and electrical properties of these deposited Langmuir Blodgett films were studied and characterized by UV-Visible spectroscopy (UV), Atomic force microscopy (AFM), Conductive Atomic force microscopy (C-AFM) respectively. For detailed investigations of the LB film properties, Conductive AFM is used to measure the I-V relationship of a surface of Langmuir Blodgett (LB) films of Polyaniline and Polyaniline–Zinc oxide nano-composite. The contact size of the AFM cantilever tip can be as small as a few nanometers, so, the local variation of the electrical property, which is unseen in the macroscopic level, can be observed by the I-V curve. A current ranging up to 3 nA and 20 nA have been observed in the case of PANi and PANi-ZnO nano-composite LB film, respectively. Conductive data images of the ITO substrate, PANi and PANi-ZnO nano-composite LB film on the ITO substrate obtained with an applied bias voltage of 4V showed that the distribution of current on the whole surface is almost uniform and very less inhomogeneities have been observed in the surface conductance of the PANi and PANi-ZnO nano-composite LB film. INTRODUCTION In recent years polymer-inorganic nano-composite materials have drawn attention due to their wide range of potential applications in optoelectronic devices [1] and solar cells [2]. In case of inorganic nano-materials the surface to volume ratio is high which modify the electrical, optical and dielectric properties of the polymers whereas use of inorganic nano-particles into the polymer matrix provides functionality to make them smart for improved performance and wide applications. Amongst inorganic nano-particles, ZnO nano-particles has received enormous interest due to their exclusive electrical, catalytic, electronic and optical properties [3], Whereas, polyaniline (PANi) is a widely studied conducting polymer due to good environmental stability, tunable conductivity and ease of preparation [4, 5]. The Langmuir-Blodgett (LB) technique offers the possibility of developing highly ordered, self assembled systems, in particular the intimate level of mixing at the molecular level. LB films of the polyaniline doped with different acids have been deposited on various kinds of substrates for varied applications [6-8]. EXPERIMENTAL
Materials Anil
Data Loading...
