Solar cells made more efficient

London: Scientists have reported progress in photovoltaic research as they have improved a component that will enable solar cells to use more energy of the sun and thus create a higher current. The improvement concerns a conductive oxide film that now has more transparency in the infrared region.

Similar attempts had been made before, but this is the first time that these films were prepared by a one-step process and, at the same time, stable in air. In solar cells the film has to be conductive because it constitutes the upper electrode. At the same time it has to be transparent in order for sunlight to reach the layer underneath, where the current is formed.

Transparent conductive oxides are used in any device combining electronics and light, like LEDs, solar cells, photo-detectors or even touch screens. The oxides forming this film can be made conductive by deliberately adding impurities. Zinc oxide with aluminium added is a widely used example.