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Highly oriented (110 plane parallel to the substrate) and highly photoactive α-PbO films are prepared by electrochemical anodic oxidation of Pb electrode in alkaline solution at 80 °C by polarizing at +0.3 V versus saturated calomel electrode. Within an hour of anodization, nearly 10–12 μm thick oxide film is produced which is found to be exclusively α-PbO with a preferred orientation along the 110 plane. The films show about 80% quantum efficiency and 1.55% solar to electrical energy conversion efficiency for white-light irradiation in a liquid junction solar cell containing 0.1 M Fe(CN)3−/4−6 redox solution. These values are the highest reported so far for lead oxide thin-film based solar cells.

Highly transparent, low‐resistance SnO2:F films suitable as a substrate material for thin film CdS/CdTe solar cells have been developed on 10 × 10 cm glass substrates by an ultrasonic spray pyrolysis (pyrosol) technique using dimethyltin dichloride (DMTDC) as a tin source. DMTDC, NH4F , and HF, all dissolved in water, served as the source solution. An ultrasonic vibrator operated at 1.5 MHz produced a fine spray of the source solution. It was transported, using air as a carrier gas, to moving glass plates in a belt furnace maintained at 530°C. A very high growth rate of nearly 100 Å/s was realized in this process with good homogenity, high transparency, and low resistivity. Films with a sheet resistance of less than 10 Ω/□ have been routinely prepared and their preparation technology has been well established. A proper nozzle design and exhaust system to remove the spent gases determines the technology of obtaining spot and cloud free homogeneous films in the belt furnace. A film of 5000 Å thickness exhibited the lowest electrical resistivity, of 3.9×10−4 normalΩ normalcm , a mobility value of 38 cm2 V−1 s−1 , and a donor concentration of 4.16×1020 cm−3 . Films of 5000–6000 Å thickness having an average transmittance of nearly 85% in the visible range and a sheet resistance of around 8 Ω/□ were used as transparent conducting oxide film substrates to fabricate thin film CdS/CdTe solar cells. A solar energy conversion efficiency of over 14% was achieved. © 1999 The Electrochemical Society. All rights reserved.

Oxide films on Al and an Al-Sn alloy were analyzed by x-ray photoelectron spectroscopy (XPS) after immersion in 3.5% sodium chloride (NaCl) solution. Results showed Sn exhibited both Sn 2+ and Sn 4+ oxidation states in the oxide film. It was proposed that incorporation of these cations in the film would result in generation of more anionic and cationic vacancies in aluminum oxide (Al 2 O 3 ), leading to active dissolution of Al.

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