Dasarao K. Murti

Performance evaluation of polycrystalline thin film CdS liquid junction photovoltaic cells

Abstract Photo-electrochemical studies of CdS films, deposited on NESA substrates by various techniques, were performed in aqueous polysulphide solutions and the output characteristics of the cells (CdS film polysulphide electrolyte/Pt) were measured. Films of CdS were prepared by vacuum evaporation, chemical bath deposition, spin coating/pyrolysis and electrodeposition. In the present study, the highest open circuit voltage ( V oc ) 0.6 V and short circuit current density ( J sc ) 0.4 mA/cm 2 due to illumination at a light intensity of 75 mW/cm 2 were obtained with CdS films prepared by spin coating followed by pyrolysis. The efficiency of photoelectrochemical cells employing such polycrystalline CdS films is about an order of magnitude lower than that obtained with single crystal CdS.

Electron injection from bis(4-dimethylaminophenyl)squaraine into (4-butoxycarbonyl-9-fluorenylidene)-malononitrile

The injection of photo-excited electrons from bis(4-dimethylaminophenyl)-squaraine into (4-butoxycarbonyl-9-fluorenylidene)malononitrile was studied by using the xerographic discharge technique. The present study has demonstrated for the first time that electrons can be injected from a squaraine into an electron transport layer. The photoinjected current data, analysed in terms of Schottky emission model, indicate that the injection barrier height at the squaraine/BCMF interface is 0.24 eV.