Development of SnS2/rGO/Pd sensors for hydrogen detection

• Grant number: 24/22792-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: July 01, 2025
• End date: January 31, 2028
• Field of knowledge: Engineering - Materials and Metallurgical Engineering
• Principal Investigator: Valmor Roberto Mastelaro
• Grantee: Julia Coelho Tagliaferro
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

Hydrogen (H2) is a promising gas to replace fossil fuels due to its potential as a renewable energy source with zero carbon emissions. However, H2 has safety challenges, such as high propensity to leak, being an odorless gas and highly flammable. H2 is explosive in concentrations greater than 4% by volume, which makes it essential to develop sensors that combine high response and selectivity, while maintaining an operating temperature close to room temperature. Recently, studies with transition metal dichalcogenides (TMDs) have shown that they are good candidates for application as gas sensors. Among the TMDs, the SnS2 compound has been applied as a sensor for different types of gases, but it has still been little explored as an H2 sensor. In this context, we are proposing the development of H2 sensors based on the SnS2 dichalcogenide compound forming a heterojunction with reduced graphene (rGO) forming the SnS2/rGO compound, and decorated with palladium (Pd) particles. The formation of a heterostructure of SnS2 with rGO should lead to a significant reduction in the operating temperature of the sensor due to the electrical properties of rGO. Studies in the literature show that palladium (Pd) decoration has a positive influence on the sensitivity and selectivity of the material in relation to H2 gas. The effect of the size of palladium nanoparticles on the sensor properties will be carried out through the use of two different deposition techniques, by chemical route and magnetron sputtering, with the magnetron sputtering technique allowing the deposition of "single atoms". The influence of the presence of defects in the sensor material will also be evaluated. For this, we are proposing to carry out a BEPE scholarship aiming to investigate the influence of the creation of crystalline defects generated by ionic irradiation on the properties of SnS2-based sensors, and how these properties compare with those of samples decorated with palladium nanoparticles.