Luminescent Photoelectrochemical Cells. 7. Photoluminescent and Electroluminescent Properties of Cadmium Sulfo-Selenide Electrodes

摘要

Photoelectrochemical cells (PECs) are being widely studied as devices for optical energy conversion. The excited-state properties of the semiconductors around which PECs are constructed are crucial to efficient energy conversion. We have employed luminescence as a probe of these excited-state-properties, generally using materials such as n-type CdS:Te(Te-doped CdS) which exhibit subband gap emission. Recently we examined emission of band gap energy from n-type CdS and CdSe, two materials which have been used extensively in PEC studies. Since these two compounds form solid solutions over the entire composition range, the mixed compounds represent a natural extension of our emissive studies. We report herein that luminescence from samples of n-type, single-crystal CdSXSe1-X can be used to probe interfacial charge-transfer events relevant to PECs. Specifically, we demonstrate that photoluminescence (PL) can be perturbed and electroluminescence (EL) initiated by interfacial charge-transfer processes.