Jaypee Institute of Information Technology

About: Jaypee Institute of Information Technology is a education organization based out in Noida, Uttar Pradesh, India. It is known for research contribution in the topics: Cluster analysis & Wireless sensor network. The organization has 2136 authors who have published 3435 publications receiving 31458 citations. The organization is also known as: JIIT Noida.

Structural and vibrational properties of ZnO nanoparticles synthesized by the chemical precipitation method

Abstract: In this article we study the structural and vibrational properties of ZnO nanoparticles. The details of process and mechanism responsible for the synthesis of nanoparticles by a high yield yet facile chemical precipitation method are explained. The prepared nanomaterial was subjected to various characterizations. Elemental composition of ~30 nm average size nanoparticles was evident through transmission electron microscope (TEM) and energy dispersive X-ray spectroscopy (EDS). Identification of hexagonal wurtzite phase and determination of lattice parameters, crystallite size, strain, crystallinity index, Zn O bond length, Young's modulus, specific surface area, and dislocation density of prepared ZnO nanocrystallites were revealed through extensive X-ray diffraction (XRD) analysis. Vibrational properties of prepared nanoparticles are determined through micro-Raman (μR) and Fourier transform infrared (FTIR) spectroscopies. The FTIR and micro-Raman investigations of Infrared and Raman active vibrational modes of ZnO nanoparticles are not only mutually supportive but more significantly, the vibrational properties thus determined are highly correlated with the structural properties determined through TEM, EDS and XRD investigations.

Structural and optical properties of unannealed and annealed zno nanoparticles prepared by a chemical precipitation technique

Abstract: In this paper we report the structural, electronic and optical properties of ZnO nanocrystals synthesized by a facile chemical method. ZnO nanoparticles prepared by this method were investigated employing X-ray diffraction (XRD), Transmission electron microscope (TEM), Atomic force microscope (AFM), Fourier transform infrared (FTIR), UV–Visible and Fluorescence (FL) spectroscopy. In order to study the effect of annealing on ZnO nanoparticles, we have analyzed pre- and post-annealed nanoparticles. It was observed that annealing treatment removes the impurities and consequently enhances the purity of ZnO nanoparticles without influencing their wurtzite phase. The absorption and excitation transitions occurring in annealed ZnO nanoparticles are similar to those in unannealed ZnO; however, some fluorescence emissions are altered. On the one hand, annealing assists in obtaining the pure ZnO nanoparticles without affecting their size and crystal structure; on the other hand channels of radiative combination are affected by the annealing process.