Advanced structural studies of metal oxide nanoparticles for development of the pair distribution function from electron total scattering

• Grant number: 25/05077-9
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• Start date: June 01, 2025
• End date: May 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: João Batista Souza Junior
• Grantee: Victor Secco Lemos
• Supervisor: Ute Kolb
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil
• Institution abroad: Johannes Gutenberg University Mainz (JGU), Germany
• Associated to the scholarship: 22/13144-0 - Study of the structural disorder on semiconductor nanomaterials using advanced electron diffraction techniques, BP.DD

Abstract

Solids presenting at least a dimension in the nanometer scale (1-100 nm) present different properties when compared to their bulk counterparts. Synthesizing these nanomaterials while controlling the properties affects their efficiency in these devices. The main influence on the properties of these nanomaterials arises from size effects, where we can define a nanostructure, equivalent to the microstructure present in bulk materials. Hence, developing new methods to analyze the nanostructure is essential to improve the nanotechnology field. In this context, the atomic pair distribution function (PDF) became an established method and gains significant attention in the scientific community. The PDF is obtained through the sine Fourier transform (FT) of the total scattering signal of the sample while ensuring there is no inelastic or multiple scattering. The FT yields results related to the atomic pairs and their probability of being at a certain distance from one another. This analysis brings invaluable local information about the structure and can be done with X-ray, neutron, or electron total scattering. Total scattering data inherently brings information from the first neighbors, long-range order, and defects all at once, since it encompasses the Bragg peaks and diffuse scattering. In this work, we aim to improve the PDF from electron total scattering by using standard materials such as metal oxides to characterize the instrumental contribution and optimize acquisition conditions. We are also going to continue improving and automating the data processing. One of the main goals of this BEPE project is the specialization of the student in electron diffraction acquisition techniques and theory, using and comparing different detectors and equipment to advance the method to quantitative structure determination.