Tough, self-healable, antifreezing and redox-mediated gel polymer electrolyte with three-role K3[Fe(CN)]6 for wearable flexible supercapacitors

Abstract

Supercapacitors exhibiting toughness, selfhealing, and high specific capacitance have practical significance for use in flexible and wearable electronic equipment. To meet these requirements, a novel multifunctional gel polymer electrolyte (GPE) consisting of polyvinyl alcohol (PVA)-sodium alginate (SA)-K 3 [Fe(CN)] 6 -Na 2 SO 4 was prepared. In this GPE, K 3 [Fe(CN)] 6 plays three crucial roles by serving as a carrier donor, ionic crosslinking agent and redoxactive mediator. Consequently, the usual conflict between the conductivity and mechanical properties of GPEs is alleviated to some extent. In addition, the electrode specific capacitance and the energy density of the assembled supercapacitor are obviously improved because of the pseudocapacitance generated from the redox reaction of K 3 [Fe(CN)] 6 . Based on this GPE, the supercapacitor exhibits outstanding bending and stretching stabilities, significant self-healing, and anti-freezing properties. Therefore, the prepared GPE and supercapacitor are promising for application in flexible and wearable electronic equipment with complex service conditions.

An ultrahigh energy density Mg–air battery with organic acid–solid anolyte biphasic electrolytes

“…38–40 So, the inhibition of surface passivation greatly reduced the anode polarization. Satisfactorily, the prepared SA/NaCl solid electrolyte possesses good compatibility with the AZ61 Mg alloy anode 41,42 with a low self-corrosion rate 6.59 × 10 −4 mg cm −2 h, which is only 1/40 of the one in 10 wt% NaCl aqueous solution electrolyte (Fig. S7†).…”

Flexible Polymer Hydrogels for Wearable Energy Storage Applications

“…[284a] PVA-sodium alginate hydrogels containing Na 2 SO 4 as the electrolyte, and K 3 [Fe(CN) 6 ] as the redox mediator can present lowtemperature resistance in addition to self-healability and flexibility due to the formation of two hybrid cross-linking networks, hydrogen bonding, and ionic coordination bonding. [289] Adding cryoprotectant materials and nanomaterials to polymer hydrogels can also lead to the inhibition of ice crystal formation. [287] Antifreezing PAM-based hydrogel electrolytes can be fabricated by introducing zinc tetrafluoroborate into the structure of the PAM hydrogel for the development of Zn-ion batteries with an operating temperature of −70 °C (Figure 18a).…”

“…[ 284a ] PVA–sodium alginate hydrogels containing Na 2 SO 4 as the electrolyte, and K 3 [Fe(CN) 6 ] as the redox mediator can present low‐temperature resistance in addition to self‐healability and flexibility due to the formation of two hybrid cross‐linking networks, hydrogen bonding, and ionic coordination bonding. [ 289 ]…”

Thermoelectric Hydrogel Electronic Skin for Passive Multimodal Physiological Perception

“…However, soft wearable devices are mechanically weak and may inevitably be susceptible to mechanical damage such as external friction, twisting, tearing, and compression in practical applications, resulting in a shortened service life. 17−20 In addition, they have two other major drawbacks, including being powered by an external power supply 21 and a complex manufacturing process. Therefore, to overcome these limitations, it is important to design a self-powered and self-healing hydrogel to monitor physiological signals in real time.…”

“…Wearable devices based on flexible electronic materials have broad application prospects in electronic skins, − intelligent healthcare monitoring, − energy harvesting, − and human-computer interactions. , The flexible and stretchable electronic devices that mimic the properties of human skin, allowing for seamless integration with the body and enabling real-time monitoring of various physiological parameters (such as body temperature, pulse, and sweat), are gradually being developed. − By detection and analysis of these bioelectrical signals, various diseases can be effectively diagnosed and treated. However, soft wearable devices are mechanically weak and may inevitably be susceptible to mechanical damage such as external friction, twisting, tearing, and compression in practical applications, resulting in a shortened service life. − In addition, they have two other major drawbacks, including being powered by an external power supply and a complex manufacturing process. Therefore, to overcome these limitations, it is important to design a self-powered and self-healing hydrogel to monitor physiological signals in real time.…”