SEMINAIRE LMGP - 23/07/2024 - Martin I. BROENS

Post-doc, Martín I. Broens

Université Grenoble Alpes, CNRS, Grenoble-INP, LMGP.

Abstract 

This seminar will present an overview of Martín I. Broens' thesis work on the synthesis of TiO₂ nanotube films (TiO₂-NTFs) and their modification with Ag nanoparticles (Ag-NPs) for Surface-Enhanced Raman Scattering (SERS). TiO₂-NTFs were prepared by electrochemical anodization of titanium in fluoride-containing electrolytes. The in situ growth of Ag nanoparticles was performed through both photo- and electrochemical methods. Various experimental parameters involved in each stage were studied to understand their impact on the resulting morphology, thereby gaining insight into the corresponding mechanisms of nucleation and growth. TiO₂-NTFs were synthesized with high reproducibility, as well as controllable morphology, and were modified with uniform coverages of Ag-NPs. The surface densities and sizes of the nanoparticles were controlled by regulating experimental conditions such as the metallic precursor concentration, photoreduction time, number of electrodeposition cycles, and the crystalline nature of the TiO₂-NTFs, among others. The modified TiO₂-NTFs were applied as substrates for enhancing the Raman scattering of adsorbed molecules, serving as SERS platforms. The performance of each substrate was evaluated using 2-mercaptopyridine as a Raman probe, revealing that high densities of Ag-NPs (2 – 4 x 10¹⁰ NPs cm^-2), with sizes ranging between 20 – 30 nm, led to the highest performance. The results of this thesis demonstrate the potential of TiO₂-NTFs modified with Ag-NPs as SERS platforms and set the basis for further application in the sensing of molecules of interest, such as agrochemical contaminants.

Short Bio/CV

Martín I. Broens studied chemistry at the National University of Córdoba (Argentina) and obtained his PhD from the Córdoba Institute of Physico-Chemistry Research in 2021. During his PhD studies, he worked on the obtention of oxide nanostructured films modified with plasmonic nanoparticles for Surface Enhanced Raman Scattering applications. From 2021 to April 2024, he worked at the Enrique Gaviola Physics Institute (Argentina) as a young post-doc in the field of condensed matter physics, with a specific focus on the synthesis and modeling of ferromagnetic nanomaterials. During his PhD studies and his work as a young post-doc, he was an Assistant Professor at the Faculty of Chemical Sciences of the National University of Córdoba. Since May 2024, he has been working on the integration of 2D MXenes into single-junction perovskite solar cells as a post-doc in the NanoMAT team at LMGP of Grenoble-INP. His current research interests cover electrochemistry and materials science at the nanoscale, in both experimental and theoretical approaches, with a particular focus on functional materials for sensing and energy-related applications.