Gel-Based Polyacrylamide/Reduced Graphene Oxide Composite Thermocells for Body Heat Harvesting in Wearable Safety Devices
Journal
Advanced Materials Technologies
ISSN
2365-709X
2365-709X
Date Issued
2026-07-17
Author(s)
Abstract
In this work, polyacrylamide (PAM)-based hydrogels are engineered as flexible matrices for ionic thermoelectric (i-TE) energy harvesting. Reduced graphene oxide (rGO) is incorporated as a functional filler to simultaneously strengthen the mechanical properties and enhance electronic transport. The degree of rGO reduction is precisely controlled via high-temperature annealing to enable systematic tuning of the structural and electrochemical characteristics of the composite hydrogels. Further, PAM/rGO thermocells are fabricated via photocrosslinking and subsequently infused with an Fe(CN)63−/4− redox electrolyte to form i-TE active materials. Among the variants, PAM-rGO150 exhibits a high ionic Seebeck coefficient of 1.38 mV K−1 along with a tensile strength of 23.32 kPa, achieving a favorable balance between TE performance and mechanical durability. To demonstrate practical applicability, an i-TE module helmet (ITMH) is assembled using 36 series-connected thermocells. The device successfully powers an LED indicator under a temperature difference as low as 8.8°C, thereby validating its capability to harvest human body heat. These results highlight the potential of rGO-reinforced thermocells as lightweight, robust power sources for next-generation self-powered wearable safety systems.
Subjects
ionic thermoelectric hydrogel
polyacrylamide
reduced graphene oxide
self-powered electronics
thermocell
wearable thermoelectric generators
Publisher
Wiley
Type
journal article