Reversible Coloration Enhanced by Electrochemical Deposition of an Ultrathin Zinc Layer onto an Anodic Nanoporous Alumina Layer

Abstract

A productive method is introduced to realize large area color electronic paper (e‐paper) with high UV resistance, heat resistance, and good significant bending properties using a color change triggered by reversible electronic change in the device structure. Reversible coloration and decoloration triggered by electrochemical deposition and desorption, respectively, of an ultra‐thin zinc (Zn) layer on a thin transparent conductive layer coated on anodic nanoporous alumina has been developed. The deposition of the ultra‐thin Zn layer triggers the formation of destructive interference, which leads to coloration. Yellow, magenta, and cyan colors were obtained in the colored state by increasing the NP‐Al2O3 layer thickness, based on Bragg diffraction theory. Reflectance of more than 70% and contrast values of more than 7 were obtained, which are nearly equivalent to those of previous e‐papers. The color images in these devices also showed high UV resistance, heat resistance, and repeated significant bending endurance. The devices can be fabricated with large areas using low‐cost manufacturing processes such as anodic oxidation, and use abundantly available materials. Our proposed device provides low‐cost and flexible large area color e‐paper for outdoor use.

Reversible Metal Electrodeposition Devices: An Emerging Approach to Effective Light Modulation and Thermal Management

“…[18,29,30] Ag, Bi, and Cu are the most widely studied metals for reversible electrodeposition because of their high reversibility and the use of hazard-free electrolytes. The reversible electrodeposition of Au, [31] Zn, [32] Pb [8] and other metals is rarely reported due to their poor reversibility or the need for hazardous electrolytes.The reversible metal electrodeposition device (RMED) is a novel electrochromic application that utilizes the appearance and disappearance of a metal layer to achieve spectrum control. A thin metal film with a thickness of a few tens of nanometers would be highly reflective in the visible and infrared region, making it an ideal material to achieve light and heat modulation.…”

“…[18,29,30] Ag, Bi, and Cu are the most widely studied metals for reversible electrodeposition because of their high reversibility and the use of hazard-free electrolytes. The reversible electrodeposition of Au, [31] Zn, [32] Pb [8] and other metals is rarely reported due to their poor reversibility or the need for hazardous electrolytes.…”

Bioinspired Controllable Electro‐Chemomechanical Coloration Films

“…The mixed layered structures underneath their skins contribute to the alternative interference colors by absorbing or exuding the water molecules in the cuticle . Inspired by these natural creatures, artificial color structural materials upon the external stimuli such as electrical field, humidity, mechanical force, and concentration of specific molecules were highly pursued for application in sensors, optical filters, anticounterfeiting, and light‐responsive/adaptive coating …”

Enhanced electrochromic properties of a TiO2nanowire array via decoration with anatase nanoparticles

“…[6][7][8][9] It is recognized that the fabrication of composite materials from two electrochromic components provides a useful technique for enhancing the optical contrast and the coloration efficiency. [10][11][12] Within the large group of existing electrochromic materials, titanium dioxide (TiO 2 ) has shown particular potential as an electro-active material, because of its high activity, strong oxidation capability and superior chemical stability. [13][14][15][16] Among the various TiO 2 nanostructures, ordered one-dimensional (1D) TiO 2 nanostructures display greater potential for electrochromic applications, because of their high surface area, facilitated Li + diffusion and good transparency, which could markedly enhance the coloration efficiency and the electron transport rate.…”