Study and characterization of optical and electrical properties of polymers with potential for the development of sensors

• Grant number: 11/20369-3
• Support type: Regular Research Grants
• Duration: February 01, 2012 - January 31, 2014
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal researcher: Daniel Souza Corrêa
• Grantee: Daniel Souza Corrêa
• Home Institution: Embrapa Instrumentação Agropecuária. Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA). Ministério da Agricultura, Pecuária e Abastecimento (Brasil). São Carlos , SP, Brazil
• Assoc. researchers: Cleber Renato Mendonça ; Juliano Elvis de Oliveira ; Leonardo de Boni ; Luiz Henrique Capparelli Mattoso ; Viviane Grassi

Abstract

In this research project is proposed the study and characterization of advanced conjugated polymers, aiming at the development of optical and electrical sensors. The polymers' linear (e.g. absorption and fluorescence) and nonlinear (e.g. multiphotonic absorption and fluorescence) optical properties, as well as the electrical properties (e.g. resistance and capacitance) will be studied aiming at potential applications in optical and electrical sensors to evaluate water quality. The polymers studied in this project include polyfluorene, polythiophene and polypirrol derivatives, among others. Concerning electrical properties, the polymers will be used as nanostructured thin films films in interdigitated electrodes for application in the Electronic Tongue, to be employed in the evaluation of water regarding contaminants, such as the pesticide paraoxon. The technique employed to deposit the polymeric films on the substrates is the (layer-by-layer self-assembly technique), which films will be characterized in terms of morphology, roughness and physic-chemical properties by techniques such as UV-Vis, FTIR, and optical, atomic force, and scanning electrical microscopy. In terms of polymers' nonlinear optical properties, we will employ the Z-scan technique to determine the two-photon absorption of the materials, as well as multi-photon fluorescence technique, aiming at developing optical sensors for water regarding contaminants. The optical and electrical characterization of the polymeric materials employing advanced techniques will provide knowledge gain of the materials' properties. In addition, this project will give background to use these materials in optical and electrical devices and sensors, for instance, for applications in water quality sensing. (AU)