A Scalable Platform for Electroresponsive Optical Displays Inspired by Cephalopods
Abstract
The richest and most diverse color patterns in the animal kingdom occur in organisms that have evolved elegant combinations of structural and pigmentary coloration elements to manipulate light efficiently. For instance, cephalopods are capable of fast and dynamic adaptation that involves the use of specialized dermal structures that modulate the animal~s appearance through multiple effects. These structures include pigmentary chromatophore organs uppermost in the dermis as well as two classes of non-pigmentary (structural) coloration cell types: iridocytes that can specularly reflect nearly any color, appearing iridescent; and leucocytes that diffusely reflect all visible wavelengths at once, producing bright white. Iridocytes comprise protein platelets of a high-refractive-index protein - reflectin - that selectively reflect light via thin-film interference, producing a variety of iridescent colors spanning the visible spectrum. Leucocytes are also reflectin-based but mostly use microspheres to reflect diffuse white light. Unlike the leucophores and iridophores, the structure-property relationships of the light-interacting elements in the chromatophore have not yet been fully characterized. Specifically, it is still not known how and to what extent the role of the pigments encapsulated within the hundreds of nanostructured granules contribute to the adaptive changes in coloration in the animals. We believe that the primary pigment distributed within the chromatophore, xanthommatin, participates in the distributed light signaling and sensing in these animals. Thus, the overarching goal of this proposal is to evaluate how and to what extent these molecules contribute to the optical and electrical feedback loop regulating the rapid changes in skin patterning and coloration during camouflage. To test this, we will build cephalopod mimetic tissue (e.g. pigment containing thin films and devices) and evaluate their ability to trigger electro-catalyzed color change with the long-term goal of creating reconfigurable optical displays inspired by how cephalopods camouflage. Specific aims of this 3- year proposal are:(1) To establish a scalable method to manufacture the primary pigment in cephalopod chromatophores, xanthommatin, and interrogate its independent role in color modulation;(2) To evaluate the electrochromic properties of xanthommatin within a generalized chromatophore mimetic tissue (e.g., a system of electrically connected pigments) and evaluate the dynamic range of color in response to a biased potential;(3) To modify xanthommatin structure and investigate its potential in selective skin patterning by templating differential colorimetric gradients within an electroactive film.The results from our study will establish fundamental relationships that link the chemical composition and the electronic function of elements of the cephalopod chromatophore that combine to contribute to the changes in skin patterning and coloration. These important findings will not only provide insight into the chemistry and physics behind how cephalopods camouflage ~ a process which has eluded scientists and engineers for decades ~ but also inform and accelerate the development of next-generation flexible displays, dye-sensitized solar cells, or light-sensitive textiles capable of absorbing and/or reflecting all wavelengths of visible light. Longer term, it ishoped that materials based on xanthommatin can be used to design a range of flexible photonic systems with broad implications for the field of wearable or flexible electronics, where photovoltaic, OLED, and solar energy conversion devices may benefit from processable cephalopod pigment derivatives.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 25, 2019
- Source ID
- N000141912137
Entities
People
- Leila F Deravi
Organizations
- Northeastern University
- Office of Naval Research
- United States Navy