Study of Ag-Bi2O3 photoelectrodes for application in solar hydrogen generation

• Grant number: 22/01901-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2022
• End date: May 31, 2023
• Field of knowledge: Engineering - Aerospace Engineering
• Principal Investigator: Argemiro Soares da Silva Sobrinho
• Grantee: Helen Caroline de Souza Barros
• Host Institution: Divisão de Ciências Fundamentais (IEF). Instituto Tecnológico de Aeronáutica (ITA). Ministério da Defesa (Brasil). São José dos Campos , SP, Brazil

Abstract

One of the main challenges currently faced by humanity is the search for carbon-free energy sources, in other words, clean, sustainable, and renewable. The use of molecular H2 as fuel stands out as a possible alternative both for its greater efficiency with respect to petroleum derivatives and for being ecologically sustainable. However, since the H2 generation process also needs to be clean, efficient, and economically viable, currently many research groups around the world study and improve techniques that satisfy these requirements. Photoelectrochemical (PEC) production of fuel H2 through water oxidation reaction (WOR) processes using sunlight is one of the methods with the greatest potential for practical applications. However, some challenges still need to be overcome for this technology to be applied on large scale. Among these, the search for new materials to be used as photoanodes in PEC cells is a critical issue. In this context, the metal oxides of the A2O3 family are materials used in a wide variety of applications due to their exceptional properties, such as high chemical, mechanical and thermal stability, in addition to presenting a significant technological potential due to their applications in optoelectronics and photonics. The Bi2O3 is known to be a non-toxic and non-carcinogenic compound, with a bandgap between 2.0-2.8 eV, in addition to having high catalytic activity. However, there is still a lack of work in the literature studying its potential as a photoelectrode in the PEC process and its ability to generate H2 via ROA processes. Thus, in order to contribute to the search for an ideal photocatalyst to be used as a photoelectrode in the production of H2 via PEC processes, in this work we propose to carry out a systematic study focused on the synthesis and characterization of Ag-Bi2O3 films. The objective of the study is to evaluate how the parameters of synthesis and growth of photoelectrodes influence their physical and chemical properties and, consequently, to investigate how these properties interfere in the production of H2 via PEC processes.(AU)