No Cover Image

Journal article 144 views 2 downloads

The structural impact of water sorption on device-quality melanin thin films / Andrew J. Clulow; A. Bernardus Mostert; Margarita Sheliakina; Andrew Nelson; Norman Booth; Paul L. Burn; Ian R. Gentle; Paul Meredith

Soft Matter, Volume: 13, Issue: 21, Pages: 3954 - 3965

Swansea University Author: Meredith, Paul

Check full text

DOI (Published version): 10.1039/c6sm02420c

Abstract

The melanins are a class of pigmentary bio-macromolecules ubiquitous in the biosphere. They possess an intriguing set of physico-chemical properties and have in particular been shown to exhibit hybrid protonic-electronic electrical conductivity, a feature derived from a process termed chemical self-...

Full description

Published in: Soft Matter
ISSN: 1744-683X 1744-6848
Published: 2017
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa33930
Tags: Add Tag
No Tags, Be the first to tag this record!
Abstract: The melanins are a class of pigmentary bio-macromolecules ubiquitous in the biosphere. They possess an intriguing set of physico-chemical properties and have in particular been shown to exhibit hybrid protonic-electronic electrical conductivity, a feature derived from a process termed chemical self-doping driven by the sorption of water. Although the mechanism underlying the electrical conduction has been established, how the sorbed water interacts with the melanin structure at the physical level has not. Herein we use neutron reflectometry to study changes in the structure of synthetic melanin thin films as a function of H2O and D2O vapour pressure. Water is found to be taken up evenly throughout the films, and by employing the contrast effect, the existence of labile protons through reversible deuterium exchange is demonstrated. Finally, we determine a sorption isotherm to enable quantification of the melanin-water interactions.
College: College of Science
Issue: 21
Start Page: 3954
End Page: 3965