Photoluminescence and ultraviolet photoresponse in ZnO nanophorsphors prepared by thermal decomposition of zinc acetate

¹Department of Electronics and Communication, University of Allahabad, Allahabad 211002, India

²Nanotechnology Application Centre, University of Allahabad, Allahabad 211002, India

Adv. Mater. Lett., 2011, 2 (4), pp 298-302

DOI: 10.5185/amlett.indias.210

Publication Date (Web): Apr 08, 2012

Copyright © IAAM-VBRI Press

E-mail: mishra_sheo@rediffmail.com

Abstract

In the present work, simple, low-cost, and direct route is used for the UV- photodetection and photoluminescent zinc-oxide nanoparticles (NPs) by decomposing zinc acetate in air at 400 ⁰C for 12 hrs. The X-ray diffraction (XRD) result indicates that the synthesized ZnO NPs is pure and single crystalline structure with wurtzite type. The crystallite size of the ZnO nanoparticles is in the range of 20–50 nm and average crystallite size of synthesized nanoparticles is found to be ~33 nm. The synthesized ZnO NPs exhibits several photoluminescence peaks centered at 396 nm, 418 nm, 441 nm, 481 nm and 522 nm. The time-resolved rise and decay of photocurrent spectrum shows initial significant increase in photocurrent and, subsequently falls gradually under UV-illumination. The photocurrent abruptly falls when illumination is turned off. The variation of photo and dark-current with applied field is found to follow power-law i.e I α V. At low voltage the behavior is sub-linear which becomes super-linear at high voltages. The ZnO NPs is found to have double traps of 0.59 eV and 0.67 eV.

Keywords

Photoconductivity, XRD, ZnO, nanophosphors