Electrophysical and Optical Characteristics of thin Doped FTO Films for Optoelectronics and Photovoltaics
Abstract
FTO, FTO:Ce, FTO:Ce films were synthesized by the sol-gel method and spray pyrolysis method. Their electrophysical and optical characteristics were determined. It was found that the introduction of graphene and cerium into the FTO films leads to an increase in electrical conductivity. High temperatures lead to graphene burnout and a change in the photoluminescence spectrum. Luminescence of Ce3+ and Ce4+ is observed in nanostructured thin films, its intensity in graphene-containing films decreases after carbon burnout. A wide luminescence band in the SL of the FTO:Ce film at 350-450 nm corresponds to the radiation of Ce<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup>, and the SL of the FTO:C:Ce film at 530-550 nm is identified as the radiation of Ce<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4+</sup>. The intensity of the luminescence band in graphene-containing FTO:C:Ce films decreases by 4.8 times compared to FTO:Ce films. The change in the charge state of the cerium ion is associated with its reduction during carbon burnout. The fact of graphene burnout is confirmed by a decrease in the electrical conductivity of the samples. The developed materials can be used in solar energy and optoelectronics.