Polydopamine-Based Multifunctional Hydrogel for Flexible Supercapacitor and Pressure Sensor Applications

Abstract

Flexible energy storage devices and sensors are two key factors for wearable electronics. Designing a multifunctional component that combines a sensor and high-performing energy storage is exciting but remains a great challenge. Here, a multifunctional hydrogel with mechanical properties has been prepared by introducing polydopamine (PDA) into a chemically crosslinked network of poly(vinyl alcohol) (PVA) and poly-(ethylene glycol) (PEG). A film electrode containing PDA is grown in situ on the hydrogel, and the resultant device can be employed as a supercapacitor and pressure sensor simultaneously. The supercapacitor exhibits an areal specific capacitance of 210.2 mF cm −2 at a current density of 0.2 mA cm −2 . As a flexible sensor, the device has a broad pressure range and good sensitivity (0.57 kPa −1 ) with a pressure range of 0−5 kPa. The device can stably detect human motion from a gentle wrist pulse to tight clutching, providing a solution for integrating energy storage devices with functional sensors in wearable electronic applications.

Bioinspired Low Hysteresis Flexible Pressure Sensor Using Nanocomposites of Multiwalled Carbon Nanotubes, Silicone Rubber, and Carbon Nanofiber for Human–Computer Interaction

“…It shows that as the pressure increases, the signals of resistance change at the same strain in the experiments and remain basically the same. In addition, the sensitivity, response time, and sensing range are analyzed by comparison with recent literature studies, − and it can be seen that the present PMCI has a fast response time, higher sensitivity, and wider sensing range as shown in Figure h. Comparisons with other properties of pressure sensing reported in the relevant literature are detailed in Table S1.…”

Polydopamine‐Enabled Biomimetic Surface Engineering of Materials: New Insights and Promising Applications

“…the applicability of modified surfaces, making them suitable for a wide range of practical applications such as electrochemical energy storage, conversion, conversion, photothermal therapy, bioengineering, adhesives, separation, purification, sensors, environment protection. [237][238][239][240][241][242][243][244][245][246][247] Moreover, the DA polymerization technique of PDA deposition is quite straightforward, costeffective, has a material-independent coating ability and does not require high-maintenance sophisticated instruments, unlike many other thin film deposition techniques. [237] A good adhesion can also be observed between the substrate and thin film in the DA assisted modification technique.…”