Synthesis, characterization and applications of some nanomaterials

In this paper we are reporting the different methods of synthesis and characterization of gold colloid, silver colloid and Multiwall carbon nanotube based composites and the potential applications. Three types of gold colloids (negative, neutral, positive) were produced by chemical reduction of uric chloride using either sodium citrate or sodium borohydride or diethyl amino pyridine (DMAP) as reducing agents. Silver colloid was produced by reduction of silver nitrate solution. Multiwall Carbon Nanotubes (MWCNT's) based composites are synthesized using solvent casting method. The formation of Au and Ag nanoparticles was confirmed by the appearance of surface Plasmon absorption maxima at 560 and 420 nm for Au and Ag nanoparticles respectively using UV-Visible spectroscopy. All these nano materials and MWCNT based composites are characterized using SEM, TEM, AFM and XRD. XRD analysis of gold and silver colloids revealed all relevant Bragg's reflections corresponding to the FCC crystal structure as given in the JCPDS data for gold and silver colloid. However some new peaks which do not belong to the above structure were also present in the data for both Au and Ag. In this paper we are also reporting the possibility of using Polyvinylidene Fluoride (PVDF)/CNT composite as strain sensors. Different weight percentage (2 Wt%, 3 Wt%, 4 Wt %) of CNT-PVDF polymer nanocomposite films are prepared and they are characterized using various techniques and reported. The strain and defect measurements using the CNT-PVDF nanocomposite as a novel Non-destructive technique (NDT) is briefly explained.