Optical and photoelectronic properties of melanin

Authors :: G. Quartucci
E. Mezzenga
P. Carmone
P. F. Biagi
R. Cicero
Marianna Ambrico
Teresa Ligonzo
Giuseppe Perna
Vincenzo Augelli
Luigi Schiavulli
Anna Gallone
M. Lastella
Vito Capozzi
M. Pallara
A. Minafra
Source :: Thin solid films, 511/2 (2006): 362–366., info:cnr-pdr/source/autori:V. Capozzi, G. Perna, P. Carmone, A. Gallone, M. Lastella, E. Mezzenga, G. Quartucci, M. Ambrico, V. Augelli, P.F. Biagi, T. Ligonzo, A. Minafra, L. Schiavulli, M. Pallara, R. Cicero/titolo:Optical and photoelectronic properties of melanin/doi:/rivista:Thin solid films (Print)/anno:2006/pagina_da:362/pagina_a:366/intervallo_pagine:362–366/volume:511%2F2
Publication Year :: 2006
Publisher :: Elsevier BV, 2006.
Abstract: A study of the structural, optical and electrical properties of synthetic and natural melanin by means of X-ray diffraction, absorption and photocurrent techniques is reported. The model of the natural melanin film as a network of nano-aggregates of polymeric units based on the indolic structure is proposed to explain the X-ray diffraction results. The shape of the absorption spectra is similar to that of amorphous and disordered semiconductors, with a very strong, broad band UV and visible absorption and an optical gap value of about 0.5 eV. Photosensitivity to sun spectra has been demonstrated by photoconductivity measurements of synthetic melanin pellets under AM1 light source illumination.