Showing papers by "Pawan K. Khanna published in 2005"
TL;DR: In this paper, the reduction of silver salt in aqueous PVA with SFS is done for the first ever time, and the solutions and the films are characterized by using UV-vis, photoluminescence (PL), FTIR spectroscopy, XRD, SEM, TEM and thermal analysis.
356 citations
TL;DR: In this paper, a reduction of the silver salt in aqueous aniline leads to the formation of silver nanoparticles which in turn catalyze oxidation of anilines to polyaniline.
216 citations
TL;DR: In this paper, polyvinyl alcohol (PVA) stabilized gold nanoparticles have been prepared in aqueous medium using two different reducing viz., hydrazine hydrate, a stronger reducing agent and sodium formaldehydesulfoxylate (SFS), a slightly weaker reducing agent.
103 citations
TL;DR: In this article, the synthesis of CdS embedded in polyvinyl alcohol (PVA) has been performed via two different routes at room temperature and the composite films have been prepared by vacuum evaporation of solvent on a glass surface.
71 citations
TL;DR: In this paper, a single-step polymerization process for the direct synthesis of the conducting emeraldine salt (ES) phase, without the need of doping, dedoping, and redoping of the polymer.
Abstract: Polyaniline (PANI) doped with p-toluene sulfonic acid was synthesized by chemical polymerization method using (NH4)2S2O8 as an oxidizing agent. This is a single step polymerization process for the direct synthesis of the conducting emeraldine salt (ES) phase, without the need of doping, dedoping, and redoping of the polymer. Presence of a free carrier tail at higher wavelength, characteristic of extended coil conformation along with a sharp polaronic peak is observed in the UV–vis spectrum of doped PANI in m-cresol solvent. FT-IR studies show the characteristic peaks of ES phase along with a sharp peak at 1120 cm−1 representing vibration band of the dopant ion. Clumps of small fibers resulting in a sponge-like structure was observed under scanning electron microscope. Thermal studies revealed a three-step decomposition pattern. Conductivity is found to increase with an increase in the temperature showing “thermal activation behavior.” Decrease in resistance with increasing humidity is observed in a broad range of humidity. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2161–2169, 2005
53 citations
TL;DR: In this paper, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Visible spectroscopy and thermogravimetric analysis (TGA) were used to characterize nanocrystalline indium particles.
46 citations
TL;DR: Nanocrystalline indium phosphide has been synthesized via catalytic cleavage of P C bond in n -trioctylphosphine by indium nanoparticles at a temperature between 200 and 360 °C under an atmosphere of argon as discussed by the authors.
37 citations
TL;DR: In this article, the synthesis of octahedral shaped PbSe quantum dots at higher synthesis temperature is reported, which includes the reaction between lead oleate and trioctylphosphine selenide under inert gas conditions.
Abstract: Formation of octahedral shaped PbSe quantum dots at higher synthesis temperature is being reported in this paper. The synthesis includes the reaction between lead oleate and trioctylphosphine selenide under inert gas conditions to produce PbSe. TEM, SEM, XRD and EDS were used to characterize the samples. The SEM exhibited the formation of spherical shaped nanocrystals at temperature below 140 and octahedral shaped nanoparticles at higher temperatures. Moreover, the TEM also showed the well resolved (111) lattice fringes proving that the nanocrystals were crystalline in nature. Synthesis of highly pure PbSe nanocrystals was another interesting aspect of this research.
11 citations