Nucleotide‐Tackified Organohydrogel Electrolyte for Environmentally Self‐Adaptive Flexible Supercapacitor with Robust Electrolyte/Electrode Interface

Abstract

Hydrogel electrolytes have attracted enormous attention in flexible and safe supercapacitors. However, the interfacial contact problem between hydrogel electrolyte and electrodes, and the environmental instability are the key factors restricting the development of hydrogel‐based supercapacitors. Here, a nucleotide‐tackified adhesive organohydrogel electrolyte is successfully constructed and exhibits freezing resistance and water‐holding ability based on the water/glycerol binary solvent system. Adenosine monophosphate enables the organohydrogels to possess outstanding adhesion and mechanical robustness. The robust adhesion can ensure close contact between the organohydrogel electrolyte and electrodes for constructing an all‐in‐one supercapacitor with low interfacial contact resistance. Impressively, the integrated organohydrogel‐based supercapacitors display an areal specific capacitance of 163.6 mF cm−2. Besides, the supercapacitors feature prominent environmental stability with capacitance retention of 90.6% after 5000 charging/discharging cycles at −20 °C. Furthermore, based on the strong interfacial adhesion, the supercapacitors present excellent electrochemical stability without delamination/displacement between electrolyte and electrodes even under severe deformations such as bending and twisting. It is anticipated that this work will provide an encouraging way for developing flexible energy storage devices with electrochemical stability and environmental adaptability.

Reversibly Stretchable Organohydrogel-Based Soft Electronics with Robust and Redox-Active Interfaces Enabled by Polyphenol-Incorporated Double Networks

“…In addition, the EIS characterization showed that a more vertical straight line was evident for the Agar/PAM-TA/EG compared with Agar/PAM at low frequency (Figure G), while the semicircular arc in the high-frequency region indicated a much lower R ct of the TA-gel. These features might have resulted from the hydrophilic TA molecules combined with the low-surface-energy EG to promote the wetting and material diffusion inside the microporous AC electrodes (Figure S9A,B), and the intimate adhesion of the gel–electrode interface could benefit as well . In addition, the solid-state supercapacitor device with the environmentally stable organohydrogel electrolyte was found to sustain 10 000 charge–discharge cycles with >80% performance retention, and to keep elasticity and ∼44% capacitance after 6-month storage (Figure S9C,D), showing the potential for long-term operation.…”

Highly Deformable, Conductive Double-Network Hydrogel Electrolytes for Durable and Flexible Supercapacitors

“…Both the front sides of the gel and ACC were clamped using the tensile machine and displaced at a velocity of 100 mm min –1 . The interfacial toughness was calculated as 2 F / w , − where F is the steady force during peeling and w is the sample width.…”

Constructing Flexible All‐Solid‐State Supercapacitors from 3D Nanosheets Active Bricks via 3D Manufacturing Technology: A Perspective Review

“…[11,12] On the other hand, the development of hydrogel-based electrolytes (high flexibility and high security) and non-hydrogel-based electrolytes (high voltage window and low temperature resistance) with multiple characteristics (stretchable, self-healing, and compressible) is also critical for flexible all-solid-state supercapacitors. [13][14][15] Ultrathin 2D nanomaterials (including carbon-based and metallic nanosheet materials) with high specific surface area play an important role in improving the capacitance characteristics of supercapacitors. [16][17][18] However, during the electrode preparation process, the irreversible stacking of 2D nanosheets caused by van der Waals force, greatly reduces the available surface area and hinders the transport of electrolyte ions, which affects the specific capacitance and rate performance of electrode materials.…”

“…[ 11,12 ] On the other hand, the development of hydrogel‐based electrolytes (high flexibility and high security) and non‐hydrogel‐based electrolytes (high voltage window and low temperature resistance) with multiple characteristics (stretchable, self‐healing, and compressible) is also critical for flexible all‐solid‐state supercapacitors. [ 13–15 ]…”