Development of perovskite and Nb2O5 films aiming at the stability of perovskite solar cells

• Grant number: 22/10998-8
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: October 01, 2022
• End date: September 30, 2025
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Carlos Frederico de Oliveira Graeff
• Grantee: Gabriel Leonardo Nogueira
• 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

The advent of perovskite solar cells based on hybrid lead halide excited the photovoltaic community due to the efficient conversion of sunlight into electricity that already reached 25%. The unprecedented progress within a very short time and a notable performance and easy processability opened a new era in optoelectronic technologies. Although, there are instabilities in humidity conditions, air, heat, or long-term exposition to light, which are barriers to the development and commercialization of perovskite solar cells, preventing new applications and the reach of new benchmarks. Among the organic-inorganic hybrid lead halide compounds with organic cations, the methylammonium lead-iodide (CH3NH3PbI3) stands out. The low stability of these compounds can be related to the weak interaction between the lead halide structure and the organic cations, which results in water-soluble products. Therefore, a promisor approach is to replace the organic cations with inorganic ions that improve the stability of the perovskite structure. Outstanding results have been achieved with cesium (Cs), but potassium (K) remains less explored. Besides, other solar cell components, such as the electron (ETL) and hole transport layers (HTL), can affect the general device instabilities. For example, the use of titanium dioxide (TiO2) as ETL under UV light creates superoxide radicals and causes a perovskite decomposition. Here, the proposal is to reach an improved stability perovskite formation by the ion replacement and by assembling the solar cells using highly stable ETLs as niobium oxide (Nb2O5). Once the study of the basic working principles of perovskite solar cells is still delayed compared to its technical development, a better comprehension of the working mechanism of these materials will contribute to achieving reliable devices suitable for commercial applications.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ASSUNCAO, JOAO PEDRO F.; LEMOS, HUGO G.; ROSSATO, JESSICA H. H.; NOGUEIRA, GABRIEL L.; LIMA, JOAO V. M.; FERNANDES, SILVIA L.; NISHIHORA, RAFAEL K.; FERNANDES, RICARDO V.; LOURENCO, SIDNEY A.; BAGNIS, DIEGO; et al. Interface passivation with Ti₃C₂T_x-MXene doped PMMA film for highly efficient and stable inverted perovskite solar cells. JOURNAL OF MATERIALS CHEMISTRY C, v. 12, n. 2, p. 13-pg., 2023-11-28. (20/12356-8, 20/16470-0, 21/03379-7, 22/10998-8, 13/07296-2, 19/22183-6, 20/15632-6)