A comparison of phosphor preparation methods was carried out. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and photoluminescence measurements were used to evaluate the methods. The most suitable for DC electroluminescence (DCEL) was found to be a thioacetamide synthesis. The DCEL forming process was investigated using Laser-Raman spectroscopy. This showed no changes in copper concentration in the formed layer of a DCEL device following the forming process, suggesting that the forming process may be due to oxidation. Indium tin oxide (ITO) conductive-coated plastic was used successfully as a replacement for ITO-coated glass in DCEL devices and methods were developed for the use of cross-linked linseed oil as a binder in DCEL panels, producing a very flexible phosphor/binder layer. The feasibility of producing infra-red emitting electroluminescent devices for particular applications was investigated. ZnCdS: Cu layers were incorporated into DCEL, and ACEL devices. The DCEL devices showed a strong photoelectric effect. The ACEL devices produced infra-red emission. Further investigation of the photoelectric effect in DCEL and ACEL devices was carried out and work functions were determined for a variety of systems.