Electrical characterization techniques for perovskite solar cells

• Grant number: 24/03707-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2024
• End date: March 31, 2025
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Carlos Frederico de Oliveira Graeff
• Grantee: Gabriel Dias Trevisan
• Host Institution: Faculdade de Ciências (FC). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil
• Associated research grant: 20/12356-8 - Stability optimization of perovskite solar cells, AP.TEM

Abstract

Perovskite solar cells (PSCs) are among the emerging photovoltaic technologies due to their superior optoelectronic properties. A notable efficiency enhancement of solution-processed PSCs was achieved after only 15 years of research (from 3.8% to 26%). At the current stage, the characterization and diagnostic protocols are essential to pave the transition towards commercial viability. Although well-established, the stand-alone current-voltage (JV) measurements do not provide insight into the nature of the dynamic processes that determine and limit the performance of PSCs. These phenomena can be evaluated by applying disturbances to the system through an external signal and analyzing the response. The impedance spectroscopy deals with small disturbances along the frequency domain, whereas the photo-CELIV technique deals with voltage and light disturbances. Such methods stand out for complementing conventional JV characterizations. However, despite the ease of implementation, they can present interpretation challenges and require care for performing the measurements. In this project, we propose the study of double-cation mixed perovskite solar cells with formulation Cs0.17FA0.83Pb(I0.83Br0.17)3, both in a conventional (n-i-p) and an inverted (p-i-n) architecture. Once the modifications in the PSCs layers and interfaces affect their electrical behavior, one can evaluate the effects of device ageing and optimization through the buffer layers (PMMA, PEI, BCP) or dopants (MXenes). Therefore, this proposal will contribute to exploring the properties of the devices, enabling further improvements.