Development of a Powder Electroluminescent Device Enabling Control of Emission Color by Changing Humidity

Abstract

Powder electroluminescent (EL) devices have been put to practical use as auxiliary light sources because of their superior environmental resistance and ease of fabrication compared to other surface emitting devices. Recently, changes in dielectric constant due to adsorption of water molecules have been observed as changes in EL intensity against the backdrop of their excellent environmental resistance. However, this system cannot distinguish a decrease in EL intensity due to the degradation of the device. In this paper, we aim to realize a powder EL device in which changes in the absorption spectrum of the cobalt complex due to changes in humidity can be detected as changes in the emission color.