Nanostructured organic films fabricated with the Langmuir-Blodgett (LB) and layer-by-layer (LBL) techniques

• Grant number: 03/07927-0
• Support Opportunities: Research Projects - Thematic Grants
• Start date: May 01, 2004
• End date: July 31, 2008
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Osvaldo Novais de Oliveira Junior
• Grantee: Osvaldo Novais de Oliveira Junior
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Pesquisadores principais: Roberto Mendonça Faria
• Associated research grant(s): 05/53914-3 - Reimund Gerhard Multhaupt | University of Potsdam - Alemanha, AV.EXT
• Associated scholarship(s): 07/06223-0 - Langmuir and Langmuir-Blodgett films of long-chain amines studied by SFG spectroscopy, BP.MS

Abstract

This projects deals with nanostructured organic films fabricated with the Langmuir-Blodgett (LB) and layer-by-Iayer (LBL) techniques, in which the molecular control allowed by these methods is exploited to optimize electrical and optical properties of the films. Three classes of materials will be studied, viz. Luminescent polymers, azobenzene-containing polymers and nanohybrids of organic polymers and metallic oxides. With regard to the luminescent polymers, novel molecular architectures will be sought to enhance the photo- and electroluminescence of polymers based on poly(p-phenylene vinylene) (PPV) and containing ionomers. Attempts will be made to understand the mechanisms responsible for the luminescence, with particular emphasis on the Fôrster energy transfer processes and on the charge injection and transport in electroluminescent devices. As for the azobenzene-containing polymers, the focus will be in the photoisomerization and resulting properties, such as photoinduced birefringence and mass transport leading to the formation of surface-relief gratings. Nanohybrids of metallic oxides will be obtained with the LBL technique where organic polymers will serve as host matrices. The main aim is to identify nanohybrids with electrochromic and charge storage capabilities, with the latter being exploited in microbatteries. The experimental work to be performed will encompass polymer synthesis, film fabrication and characterization with several techniques, and production of prototypes of electroluminescent and charge storage devices. This will be accompanied by theoretical modeling studies not only to explain the experimental results but also to conceive novel molecular architectures with optimized properties. In some cases, use will be made of a combination of two or more materials in order to take advantage of the synergy in electrical and optical response of the materials due to molecular-level interactions. (AU)