Structural and optical properties of soluble melanin analogues with enhanced photoluminescence quantum efficiency

Author(s)

Paulin, Joao Vitor ^[1] ; Veiga, Amanda Garcez ^[2] ; Garcia-Basabe, Yunier ^{[2, 3]} ; Miranda Rocco, Maria Luiza ^[2] ; Graeff, Carlos F. O. ^{[1, 4]}

Affiliation

^[1] Sao Paulo State Univ UNESP, Postgrad Program Mat Sci & Technol, Bauru - Brazil

^[2] Univ Fed Rio de Janeiro, Inst Chem, Rio De Janeiro - Brazil

^[3] Univ Fed Integracao Latinoamer, UNILA, Foz Do Iguacu - Brazil

^[4] Sao Paulo State Univ UNESP, Dept Phys, Bauru - Brazil

• Document type: Journal article
• Source: Polymer International; v. 67, n. 5, p. 550-556, MAY 2018.
• Web of Science Citations: 1

Abstract

Melanin is a functional material of growing interest for bioelectronics. Several melanin analogues have been employed in order to fully explore its potential; in this work melanin was synthesized using dimethylsulfoxide (DMSO) and O-2 under pressure as oxidizing agent. It is shown that the products have similar functional groups and solubility; however, O-2 pressure produces more carboxylated structures and improves the synthesis reaction rate. The photoluminescence of all sulfonated melanin analogues was studied. It is shown that the material synthesized in DMSO has photoluminescence in the visible region (487 nm) with a quantum yield of (2.12 +/- 0.02)%. This good quantum yield compared to natural and synthetic melanin may open new perspectives for its use in optoelectronics applications. The origin of this effect is discussed in terms of the polymer structure. (c) 2018 Society of Chemical Industry (AU)

• FAPESP's process: 15/23000-1 - Vertical organic field-effect transistor using dyes of natural origin as active layer
• Grantee: João Vitor Paulin
• Support type: Scholarships in Brazil - Doctorate
• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support type: Research Grants - Research, Innovation and Dissemination Centers - RIDC