Luminescent sensing of volatile organic compounds (VOCs) using glassy substrates coated with lanthanide metal-organic frameworks (Ln-MOFs)

• Grant number: 23/16047-8
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date until: April 01, 2024
• End date until: August 22, 2024
• Field of knowledge: Physical Sciences and Mathematics - Chemistry
• Principal Investigator: Danilo Manzani
• Grantee: Renato Grigolon Capelo
• Supervisor: Guillermo Orellana
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Institution abroad: Universidad Complutense de Madrid (UCM), Spain
• Associated to the scholarship: 20/12280-1 - Waveguides based on oxide glasses of heavy atoms for optical sensing of gases in the UV-Vis range, BP.DR

Abstract

Fiber optic-based sensors have become a promising platform for the development of remote chemical sensing solutions, allowing in-situ and faster responses. These devices are continuously evolving and new methods of improving their performance are constantly being developed, such as the use of a chemosensing agent to generate or enhance the signal to be detected. In this regard, lanthanide metal-organic frameworks (Ln-MOFs) have shown great potential for sensing various analytes such as gases and volatile organic compounds (VOCs). This proposal aims to develop sensors based on optical fibers coated with luminescent Ln-MOFs for remote sensing. Oxide glasses are used as a substrate for the in-situ growth of Ln-MOFs synthesized from EuCl3 and carboxylate ligands, specifically those from trimesic (1,3,5-benzene tricarboxylic) and pyromellitic (1,2,4,5-benzene tetracarboxylic) acids. The Ln-MOFs are deposited on glass sheets and optical fibers, and their structural and photoluminescent properties have been investigated. The composites were exposed to different organic analytes and photoluminescence measurements revealed luminescence quenching in the presence of acetone. However, so far, our measurements have been performed just on glass sheets and without an accurate control of the analyte level. Thus, this internship project focuses on performing remote sensing tests in real time using coated glasses and optical fibers through photoluminescence measurements with high control of the analyte concentration.