Role of Mn impurity in the deterioration of ZnS:Cu, Br electroluminescent phosphors

Kutty, TRN and Revathi, R (1985) Role of Mn impurity in the deterioration of ZnS:Cu, Br electroluminescent phosphors. In: Materials Research Bulletin, 20 (1). pp. 19-25.

PDF 26.pdf - Published Version Restricted to Registered users only Download (341kB) | Request a copy

Abstract

ZnS:Cu, Br powder EL phosphors showed 6-line EPR signal at 25°C whose intensity increases with Cu content and on annealing in Zn-vapour. The signal arises from native Mn impurity. The starting material does not show any EPR signal since Mn2+ acts as an affinity potential well for a hole in ZnS, forming Mn3+ - a chemically uncommon situation in sulfides. In doped ZnS, holes are trapped at Cu such that Mn2+ persists. Deterioration of EL brightness is accompanied by the decrease in EPR signal intensity due to field assisted hole transference to Mn2+. Intentional addition of Mn in ZnS:Cu, Br decreases the brightness and shortens life time. Stable phosphors require ZnS with Mn content less than 1014 cm−3.

Item Type:	Journal Article
Publication:	Materials Research Bulletin
Publisher:	Elsevier Science
Additional Information:	The copyright of this article belongs to Elsevier Science.
Department/Centre:	Division of Chemical Sciences > Inorganic & Physical Chemistry
Date Deposited:	27 Nov 2009 09:07
Last Modified:	19 Sep 2010 05:40
URI:	http://eprints.iisc.ac.in/id/eprint/22035

Actions (login required)

View Item