journal article·2025-12-01Open access

Integrated health monitoring system with flexible asymmetric supercapacitors based on 2D Ti₃C₂ MXene and transitional metal oxides

Kaaviah Manoharan, Martin Pumera

npj Flexible Electronics· Volume 9· Issue 1

Abstract

Abstract Developing flexible, lightweight, and portable medical devices for continuous health monitoring requires compact and sustainable energy storage solutions. Traditional devices often rely on bulky wired equipment or battery-powered systems requiring frequent recharging, limiting practicality. We developed a flexible and stable asymmetric supercapacitor using MXene and transition metal oxide nanocomposite. In half cells, the electrolyte was 1M H₂SO₄; in full cells, a PVA/H₂SO₄ gel was used. Among the composites, Fe₂O₃@Ti₃C₂ showed superior electrochemical performance due to surface redox reactions enhancing pseudocapacitance. The Fe₂O₃@Ti₃C₂||Ti₃C₂ electrode delivered high specific capacitance, excellent power density, remarkable cyclic stability, and mechanical durability over 10,000 bending cycles. The assembled device successfully powered small electronics (LEDs and digital thermometers). Also, integrated with a pressure sensor to monitor human heartbeat signals in real time, with wireless data transmission to a mobile device. This work demonstrates the efficiency and applicability of Fe₂O₃@Ti₃C₂ flexible supercapacitors for next-generation wearable and biomedical electronics.
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Research context

OpenAlex topics: MXene and MAX Phase Materials · Supercapacitor Materials and Fabrication · Advanced Sensor and Energy Harvesting Materials

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