Anticorrosion coating for semiconductor in photo:electrochemical cell - where semiconductor electrode is provided with thin coating of silicon mon:oxide

摘要

The semiconductor may be mono- or poly-crystalline, amorphous or sintered, and can be of n- or p-type. In the cell, the semiconductor is in contact with an aq. or non-aq. electrolyte soln. The surface of the semiconductor to be immersed in the soln. is protected against corrosion by a homogeneous coating of silicon monoxide. The SiO2 coating is pref. 5-200 nm. thick, and may consist of a solid soln. of Si in SiO2. The semiconductor is pref. monocrystalline-, polycrystalline-, or sintered Si, theSiO coating being obtd. by vacuum vapour deposition. The electrolyte soln. is pref. an aq. soln. of LiClO4, or a non-aq. ammoniacal soln. of an alkali halide. Used esp. for cells transforming solar energy into electricity, where the invention prevents or minimises the corrosion of the semiconductor in the cell.