Highly Strong and Tough Double‐Crosslinked Hydrogel Electrolyte for Flexible Supercapacitors

Abstract

Excellent mechanical properties are indispensable for the wide application of supercapacitors and various wearable devices. In this article, a novel double‐crosslinked hydrogel electrolyte (DC‐GPE) is prepared by the combination of the hydrophobic association of acrylamide with the amphiphilic monomer AEO‐9‐AC and the ionic complexation of acrylic acid with Fe3+ for the first time by a two‐step method. Owing to the dual energy dissipation network, the DC‐GPE exhibits an excellent tensile strength of up to 3.1 MPa, an elongation at break of more than 900 % and a toughness of 18.1 MJ m−3, which is far beyond the currently reported hydrogel electrolyte. Moreover, the ionic conductivity of the DC‐GPE achieves as high as 40.1 mS cm−1, which is 3 times higher than the corresponding LiClO4 solution electrolyte (12.3 mS cm−1). Besides, the activated carbon‐based supercapacitor assembled by the DC‐GPE shows excellent electrochemical performance, which is superior to most activated carbon‐based supercapacitors. These results demonstrate that the DC‐GPE shows a great application prospect in wearable devices like supercapacitors. Significantly, the new dual physical cross‐linking strategy improves the contradiction between the strength and the toughness of the gel electrolyte materials. And provides a new solution for preparing high‐strength as well as high‐toughness gel electrolyte.

Two‐Step Deposition Approach for Lead Free (NH4)3Sb2I9 Perovskite Solar Cells with Enhanced Open Circuit Voltage and Performance

“…Production of green energy units including hydrogen, [1–6] batteries, [7–11] supercapacitors [12–14] and solar cells [15] by low‐cost methods is of great importance. Solar energy harvesting using perovskite or perovskite‐like materials is trending due to cost‐effective and simple fabrication techniques [15–29] .…”

A Dual Physical Cross‐Linking Strategy to Construct Tough Hydrogels with High Strength, Excellent Fatigue Resistance, and Stretching‐Induced Strengthening Effect

“…First, when SA x HA sIPN hydrogels were immersed in FeCl 3 solution, the formation of IC protects HA cross‐linking from dissociation during immersion. [ 69 ] Second, the decreased SDBS content after immersion could increase the association ability among hydrophobic POMA segments. [ 31 ] In addition, the synergy of HA and IC could enhance the mechanical performances of the hydrogels due to the effective energy dissipation mechanism.…”

A Powder Self‐Healable Hydrogel Electrolyte for Flexible Hybrid Supercapacitors with High Energy Density and Sustainability

“…Compared with most previously reported hydrogel electrolyte-based supercapacitors, the Ragone plot of SPMA-ZHS exhibits a higher energy density of 164.13 Wh kg −1 at the power density of 1283.44 Wh kg −1 (Figure 3G, Table S2, Supporting Information). [52][53][54][55][56][57][58][59][60][61][62][63] Cycling performance is an important indicator for the supercapacitors. Cycling stability and coulombic efficiency of SPMA-ZHS were investigated at 10 A g −1 for 5000 charge-discharge cycles.…”