Spectroscopic evaluation of the bulk and interfacial molecular orientations of organic thin films deposited onto different surfaces

• Grant number: 12/09905-3
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: September 01, 2012
• End date: January 31, 2016
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Osvaldo Novais de Oliveira Junior
• Grantee: Diogo Volpati
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated scholarship(s): 13/08864-4 - Molecular control in nanostructured films of carbon nanotubes, BE.EP.PD

Abstract

Controlling the properties of thin films at the molecular level is of utmost importance for the development of devices containing nanoscale elements. The performance of devices based on thin films relies on the orientation of organic molecules and biomolecules. Therefore, the lack of information regarding "molecular orientation" and "properties" of thin films can delay such development. An alternative to address technological problems or even to carry fundamental scientific studies is to employ techniques which allow molecular-level control and to analyze their molecular orientation on mono/multi layers. This research proposal aims at investigating the molecular orientation in organic films deposited onto different substrates. The spectroscopic analysis will be carried out in both bulk and interfaces for films deposition on substrates of different types, with goal of finding correlations between molecular orientation and optical properties of the thin films. The latter will be fabricated using the Langmuir and Langmuir-Blodgett (LB) techniques onto water, metals and inorganic semiconductors. The analysis of the molecular orientation will be carried out mainly with measurements of polarization modulation infrared reflection adsorption spectroscopy (PM-IRRAS) and sum-frequency generation (SFG). Other techniques such as micro-Raman scattering, fluorescence, UV-Vis absorption, BAM and AFM will be used as supplementary tools in the investigation of the relationship between molecular structures and film properties.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

PAVINATTO, ADRIANA; DELEZUK, JORGE A. M.; SOUZA, ADRIANO L.; PAVINATTO, FELIPPE J.; VOLPATI, DIOGO; MIRANDA, PAULO B.; CAMPANA-FILHO, SERGIO P.; OLIVEIRA, JR., OSVALDO N.. Experimental evidence for the mode of action based on electrostatic and hydrophobic forces to explain interaction between chitosans and phospholipid Langmuir monolayers. COLLOIDS AND SURFACES B-BIOINTERFACES, v. 145, p. 201-207, SEP 1 2016. (12/09905-3, 10/07178-1, 13/14262-7)

VOLPATI, D.; SPADA, E. R.; PLA CID, C. C.; SARTORELLI, M. L.; AROCA, R. F.; CONSTANTINO, C. J. L.. Exploring copper nanostructures as highly uniform and reproducible substrates for plasmon-enhanced fluorescence. ANALYST, v. 140, n. 2, p. 476-482, 2015. (12/09905-3, 11/11065-0)

VOLPATI, DIOGO; CHACHAJ-BREKIESZ, ANNA; SOUZA, ADRIANO L.; RIMOLI, CAIO VAZ; MIRANDA, PAULO B.; OLIVEIRA, JR., OSVALDO N.; DYNAROWICZ-LATKA, PATRYCJA. Semifluorinated thiols in Langmuir monolayers - A study by nonlinear and linear vibrational spectroscopies. Journal of Colloid and Interface Science, v. 460, p. 290-302, DEC 15 2015. (12/09905-3, 13/06595-6, 14/01595-0, 13/08864-4)