Device-Quality Electrically Conducting Melanin Thin Films

摘要

Studying the optical and electronic properties of biological macromolecules has remained an active area of research during the last decade. In particular, electrical transport in DNA has been the subject of extensive investigation. The condensed-phase electrical properties of proteins have also interested many, with groups even being able to produce a prototype protein-based field-effect transistor. Melanin is an ubiquitous biological macromolecule that has been shown to possess intriguing condensed-phase physical properties. These include electrical conductivity and photoconductivity as well as threshold and memory switching. Melanin is also known for its strong optical absorption that ranges from the ultraviolet (UV) to the near-infrared (NIR). These properties have been interpreted by many as evidence that melanin is an amorphous organic semiconductor Natural eumelanin is the most common form of melanin found in humans. As a photo-protectant it strongly absorbs UV and visible light and then very efficiently dissipates the potentially damaging absorbed energy as heat.