Proceedings of Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP23)
DOI: https://doi.org/10.29363/nanoge.iperop.2023.044
Publication date: 21st November 2022
Powerful modulated techniques such as Impedance Spectroscopy (IS), Intensity-Modulated Photocurrent Spectroscopy (IMPS) and Intensity-Modulated Photovoltage Spectroscopy (IMVS) are well-established to characterize optoelectronic devices under operational conditions. They are typically used in an independent way. In this presentation we will show that the combination of the three techniques provides added useful information that helps to select accurate models to fit experimental data and thus to obtain reliable data for the characterization of the physico-chemical properties of the materials these devices are constituted. The theoretical basis of this combination will be described, then several approaches to analyse solar cells and photoelectrodes for water splitting will be shown. We will start using simple elements to estimate the equivalent circuit describing the response of such systems and then evolve towards more complex systems such distributed diffusion and recombination models. Through this analysis the main limitations for the operation of these devices will be identified and, in the particular case of BiVO4 photoelectrodes used for water splitting, the ambipolar response of this electrode for the different illumination side will be unveiled.