Interfaces and Charge Transport in Melanin Thin Films and Devices

限制世界范围内废弃电气和电子设备（WEEE）的需要，对发展“无处不在的传感器网络”的兴趣，对改善医疗植入物和活组织之间生物相容性的要求，都要求对对环境和人类友好、丰富和低成本的天然材料进行彻底研究。在这种情况下，黑色素是一个有吸引力的候选者。黑色素在动植物中无处不在。例如，它可以在人类的皮肤、头发、眼睛、内耳和大脑中找到。真黑素是所有种类的黑色素中研究最多的，具有许多功能，包括光保护、金属螯合、抗氧化行为和清除自由基。真黑素还与黑色素瘤、皮肤癌和帕金森病的发展有关。除了在生物学和医学上的重要性外，物理学家和材料科学家还研究了真黑素的物理化学性质，例如光电导率和水合依赖电导率。这些特性，连同生物相容性、可生物降解性和非凡的热稳定性和光稳定性，表明真黑素在技术应用方面的巨大潜力。***尽管在以薄膜形式加工真黑素方面取得了令人印象深刻的进展-在所有溶剂中都是出了名的难溶性，但要提高对真黑素功能特性的理解并开发其技术潜力，还需要克服主要障碍。有关颜料的宏观和超分子结构以及电荷转移和输运性质的不明确方面尚未得到充分了解。***我在这个发现基金中提出的研究项目旨在推进真黑素薄膜中与其结构相关的电子和离子传输的知识。我将采用一个整体的方法，包括化学，结构，氧化还原，电子和离子的贡献，我相信这是一个理想的平台，研究复杂的自然材料，其行为受到外部因素（如大气组成或盐的存在）的显著影响。跨学科的研究将允许培养多才多艺的高素质人才，真正的“问题解决者”有能力面对我们现代的巨大挑战。***我的研究将为黑色素和其他类别的环保电子和生物电子学天然材料建立扩展的结构-性质关系提供指导，例如用于储能的生物相容性和可生物降解超级电容器，化学和生物传感器，具有改进生物相容性的植入式神经电极，并将推进对真黑色素在生物系统中的功能特性的理解。**

The need to limit the waste electrical and electronic equipment (WEEE) worldwide, the interest in developing a "ubiquitous sensor network", the requirement for an improved biocompatibility between medical implants and living tissues call for a thorough study of natural materials, environmentally and human friendly, abundant and available at low-cost. Within this context, the pigment melanin is an attractive candidate.***Melanin is ubiquitous in flora and fauna. As an example, it can be found in human skin, hair, eyes, inner ear and brain. Eumelanin, the most studied of all classes of melanin, has numerous functions that include photoprotection, metal chelation, antioxidant behavior and free radical scavenging. Eumelanin is also involved in the development of melanoma skin cancer and Parkinson's disease. Apart from its importance in biology and medicine, eumelanin has been investigated by physicists and materials scientists because of its physicochemical properties, e.g. photoconductivity and hydration-dependent conductivity. These properties, together with biocompatibility, biodegradability and extraordinary thermal and photostability, indicate the great potential of eumelanin for technological applications. ***Despite impressive progress done in the processing of eumelanin - notoriously poorly soluble in all solvents - in film form, major hurdles have to be overcome to advance the understanding of the eumelanin functional properties and to exploit its technological potential. Aspects pertaining to the ill-defined macro and supramolecular structure of the pigment as well as to charge transfer and transport properties are yet to be fully understood. ***The research program I propose in this Discovery grant aims at advancing the knowledge on electronic and ionic transport in eumelanin films as related to their structure. I will adopt a holistic approach, including chemical, structural, redox, electronic and ionic contributions, which I believe it is the ideal platform to study complex natural materials whose behavior is dramatically influenced by external factors (e.g. composition of the atmosphere or presence of salts). The interdisciplinarity of the research will permit to train versatile highly qualified personnel, real "problem solvers" capable of facing the grand challenges of our modern times.***My research will generate guidelines to build extended structure-property relationships in melanin and other classes of natural materials for environmentally benign electronics and bioelectronics, e.g. biocompatible and biodegradable supercapacitors for energy storage, chemo- and biosensors, implantable neurological electrodes with improved biocompatibility and will advance*the understanding of the functional properties of eumelanin in biological systems.**