A new red colour emitting phosphor – ZnS:Mn co-doped with Ba for electroluminescent (EL) displays

Abstract

A new Mn activated Ba co-doped ZnS phosphor shows an interesting shift in the spectral emission from amber-yellow (570 nm) to red (620 nm) colour. To realize the phosphor material physics, attempts were made to fine tune the band gap of ZnS by co-doping Ba within the concentration range 2.50–10 mol%. Ba co-doping in ZnS host was achieved by sintering BaSO 4 with ZnS at 900 °C by carbothermal reduction method. Measurement of the CIE (Commission International deEchairge) chromaticity colour coordinates ( x, y) of Zn 0.99S:Mn 0.01 and Ba 0.10Zn 0.89S:Mn 0.01 phosphors shown to be (0.53, 0.47) and (0.65, 0.32), respectively.