Flexible Polymer–Carbon Nanotube Composite with High-Response Stability for Wearable Thermal Imaging

In this work, we report a wearable thermal detector based on poly­(vinyl alcohol) and carbon nanotube (CNT) composite via photo-thermoelectric effect. Passive room-temperature human body thermal imaging is demonstrated with optimum detectivity up to 4.9 × 10⁶ cm Hz^1/2 W^–1. Highly stable photoresponse (variation < 4%) is obtained under a bending radius down to 3.5 mm. We also found that the detector photoresponse is influenced by the composite channel length because of Seebeck effect. This flexible, self-powered, and sensitive detector opens up opportunities for wearable thermal imaging and real-time health monitoring.