Proceedings of nanoGe International Conference on Perovskite Solar Cells, Photonics and Optoelectronics (NIPHO19)
DOI: https://doi.org/10.29363/nanoge.nipho.2019.069
Publication date: 21st November 2018
Halide perovskites have fascinated the research community over the past few years, mainly in the photovoltaic (PV) field. This is largely due to a combination of excellent optoelectronic properties for materials grown at low temperatures coupled to fantastic absorbing capabilities yielding highly efficient photovoltaic devices. Since the earlier reports in 2012, halide perovskite materials are on the way to deliver high PV performances, and today single junction solar cells have overpassed power conversion efficiency (PCE) of 23%. However, beyond power efficiency, other critical factors are required to allow the transition from laboratory to industrial production. This includes low manufacturing costs and long term stability which has raised major concern. Reaching the maximum theoretical performance and demonstrating simultaneously long-term stability requires further understanding of the optoelectronic properties of perovskite materials, including layered perovskites and also how they can be practically controlled. Indeed, aging causes electronic degradation in the perovskite layer and-or at the various interfaces. In this study, we present examples of dielectric profiles of Halide Perovskites (2D/3D1) using a method based on DFT calculations2,3. A dielectric confinement is found for the 2D Halide Perovskite due to the contrast of the dielectric constant between the organic and the inorganic layers. We also present examples of numerical simulation results which lead to give a physical insight into the solar cell operation and characterization5. A numerical simulation based on the SILVACO code is used to solve the classic carrier transport equation and a model to describe ionic migration is added. As examples, HTM free structures4 and tandem solar cells6 are investigated, and first results on ionic migration in the case of the PCBM/Perovskite/PEDOT:PSS architecture are presented.