Development of Nb2O5 mesoporous films for application in perovskite solar cells

• Grant number: 19/22562-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2020
• End date: February 28, 2022
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Carlos Frederico de Oliveira Graeff
• Grantee: João Pedro Ferreira Assunção
• Host Institution: Faculdade de Ciências (FC). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil
• Associated research grant: 13/07296-2 - CDMF - Center for the Development of Functional Materials, AP.CEPID

Abstract

The growing demand for electricity has led man to consume more and more the planet's natural reserves. In view of this, new sustainable ways of producing electricity have been studied, among them, the most promising is solar energy, which, converted by a solar cell (CS) through the photovoltaic effect, it generates electrical energy. Currently, of the technologies applied in CSs, those composed of hybrid perovskites organic-inorganic are the ones that attract the most attention, due to the great speed with which the technology has developed, reaching energy conversion efficiency values of 25%, with the potential to replace commercial silicon cells. When exposed to radiation the perovskite film produces pairs of electron-holes that are extracted for the external circuit. To ensure good electron extraction, it is necessary to have a high contact surface at the materials interface, so when the electron is generated, the high contact area between them allows an almost immediate injection, ensuring a good efficiency in extracting the generated electrons. Today, the most used material for formation of this mesoporous film is TiO2, however, the photocatalytic activity of this material promotes the degradation of perovskite and the reduction of cell efficiency and its useful life. Thus, this project proposes the replacement of TiO2 by Nb2O5, the which has high stability in the presence of UV light and perfectly energy levels aligned with perovskite for good cargo transfer. Furthermore, due to the abundance of niobium in Brazil, this substitution is extremely feasible, from the point economically, for the country. Through the development of this project, it is expected, the formation of films with optimized properties, contributing not only to the most efficient efficiency of the generated electrons, but also for the formation of more stable CSs.