Ionic Liquid Mediated Dispersion and Support of Functional Molecules on Cellulose Fibers for Stimuli-Responsive Chromic Paper Devices

Abstract

Functional molecules play a significant role in the development of high-performance composite materials. Functional molecules should be well dispersed (ideally dissolved) and supported within an easy-to-handle substrate to take full advantage of their functionality and ensure easy handling. However, simultaneously achieving the dissolution and support of functional molecules remains a challenge. Herein, we propose the combination of a nonvolatile ionic liquid and an easy-to-handle cellulose paper substrate for achieving this goal. First, the photochromic molecule, i.e., diarylethene, was dissolved in the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([bmim]NTf). Then, diarylethene/[bmim]NTf was supported on cellulose fibers within the paper, through hydrogen bonding between [bmim] cations of the ionic liquid and the abundant hydroxyl groups of cellulose. The as-prepared paper composites exhibited reversible, rapid, uniform, and vivid coloration and bleaching upon ultraviolet and visible light irradiation. The photochromic performance was superior to that of the paper prepared in the absence of [bmim]NTf. This concept could be applied to other functional molecules. For example, lithium perchlorate/[bmim] tetrafluoroborate supported within cellulose paper acted as a flexible electrolyte to provide a paper-based electrochromic device. These findings are expected to further the development of composite materials with high functionality and practicality.

Recent Trends in Elaboration, Processing, and Derivatization of Cellulosic Materials Using Ionic Liquids

“…These materials have high thermal stability, rapid and reversible molecular switching and have been applied in devices such as actuators, photo-optical switches, optical memory, and displays 62 dissolving layer for photochromic diarylethene on cellulose pulp fibers. Reprinted with permission from Koga et al 34 , American Chemical Society, Copyright 2017.…”

“…The composites show rapid, uniform, and vivid coloration/ decoloration upon UV/visible light irradiation. 62 Supporting the ionic liquids on cellulose fibers was achieved by room temperature solution processes. The supported ionic liquid could, in turn, support dissolved diarylethene on the cellulose fibers of the paper.…”

“…Koga et al supported diarylethene/[C 4 mim]­NTf 2 on cellulose fibers within the paper, through hydrogen bonding between [C 4 mim] cations and hydroxyl groups of cellulose. The composites show rapid, uniform, and vivid coloration/decoloration upon UV/visible light irradiation …”

Extending Cellulose-Based Polymers Application in Additive Manufacturing Technology: A Review of Recent Approaches

“…Photochromic molecules were dissolved in ionic liquid and coated on cellulose fibers through hydrogen bonding, and the light-responsive properties were investigated [ 161 ]. The prepared paper demonstrated reversible and rapid photo-responsive color changing behavior when irradiated with UV and visible light.…”

Designing of Rewritable Paper by Hydrochromic Donor–Acceptor Stenhouse Adducts

“…Over the last few decades, scientists have been working on rewritable paper. Based on molecules and materials that show color change under external stimuli, rewritable paper or materials can be reversibly written and erased under control of pH, − heat, − light, − electricity, − oxidant/reductant, solvents, and mechanical force. − Therefore, recycling of rewritable paper skips the refabrication from pulp and is environmentally friendly and energy efficient.…”