Reconfigurable Touch Panel Based on a Conductive Thixotropic Supramolecular Hydrogel

Abstract

Touch panels based on ionic conductive hydrogels perform excellent flexibility and biocompatibility, becoming promising candidates for the next-generation human−machine interface. However, these ionic hydrogels are usually composed of cross-linked polymeric networks that are difficult to be recycled or reconfigured, resulting in environmental issues. Herein, we designed a lithium ion-triggered gelation strategy to provide a conductive molecular hydrogel with thixotropy, which can be mechanically recycled or reconfigured at room temperature. In this hydrogel, lithium ions function as ionic bridges to construct supramolecular nanoassemblies and charge carriers to impart ionic conductivity. With polymer additives, the mechanical accommodability of the hydrogel was improved to meet the requirements of the daily use of touch panels. When this molecular hydrogel was fabricated into a surface capacitive touch panel, real-time sensing and reliable touch locating abilities were achieved. Remarkably, this touch panel can be reconfigured into 1D, 2D, and 3D device structures by a simple stirring−remolding method under ambient conditions. This work brings new insight into enriching the functionalities of hydrogel-based ionotronics with a supramolecular approach.

Electrochemically exfoliated covalent organic frameworks for improved photocatalytic hydrogen evolution

“…As a signicant indicator for their photophysical properties, 22 a noticeable difference in color between TTB-PB (yellow) and TTB-PT (orange) could be readily distinguished from their optical images (inset of Fig. 2c).…”

“…20,21 With high structural symmetry, three-armed TTB has been gradually recognized as an appropriate building block for novel thiophene-COFs. 22 As shown in Fig. 1a, two types of TTB-based COFs (TTB-PB and TTB-PT) were synthesized by a Schiff-base condensation reaction, in which TTB was reticulated with electron-rich 1,3,5-tris(4-aminophenyl)benzene (TAPB) or electron-decient 2,4,6-tris(4-aminophenyl)triazine (TAPT), respectively (see the ESI † for the detailed procedure).…”

Recent advances on covalent organic frameworks (COFs) as photocatalysts: different strategies for enhancing hydrogen generation

“…Hence, adjusting the p-conjugation degree of building blocks is a valid method by which to influence the photocatalytic performance. [81][82][83][84][85][86][87] Jiang et al presented four COFs (USTB-7, USTB-8, USTB-9 and USTB-10) with varying bandgaps (Fig. 8).…”

Molecular engineering of donor–acceptor sp2-carbon-linked covalent organic frameworks for enhancing photocatalytic hydrogen production

“…TFPB, TFTB and BTT are electron donor groups commonly used to enhance π-electron communication, especially BTT, which is rich in heteroatoms, planar and completely conjugated. 50 The sp 2 -carbon bond, because it effectively enhances the conjugation of COFs, is adopted to construct the COF platform. Ph-COF, Th-COF and TTh-COF are prepared by Knoevenagel condensation in a mixed solvent of o-DCB and n-BuOH under the catalysis of the inorganic base Cs 2 CO 3 (see the ESI † for experimental details).…”