A TEAM of Chinese scientists has developed a groundbreaking plastic film that converts body heat into electricity with record-breaking efficiency, bringing self-powered wearables closer to reality.

Published in Science on Friday, the study tackles a key challenge for next-generation electronics: sustainable power. As smartwatches, fitness trackers, and medical patches become ubiquitous, daily charging grows increasingly inconvenient. Thermoelectric materials, which turn temperature differences into power, offer a solution. They work via the Seebeck effect: When one side is hotter than the other, electrons flow toward the cooler side, generating current.

Historically, flexible plastics typically perform poorly due to a molecular contradiction: A material must block heat while conducting electricity well, yet materials good at one tend to be good at both.

Now, researchers at the Chinese Academy of Sciences’ Institute of Chemistry have cracked the code. Associate Professor Liu Liyao’s team created a “hierarchical porous structure” — imagine a plastic sponge with pores ranging from nanometers to micrometers. This chaotic maze blocks heat like a rugged mountain range, while the narrow bridges between pores force polymer molecules into neat rows, creating electron highways.

The results are striking: heat leakage dropped by 72%, while electrical flow increased by 52%. The film achieved a thermoelectric figure-of-merit of 1.64 at around 70°C — shattering the previous record of 1.4 for flexible materials.

In a lab test, an 10×8 cm piece attached to a person generated 9 millivolts. While modest, scaling it up could power wireless sensors and ultra-low-power electronics.

Crucially, the material is compatible with industrial printing, meaning it could eventually be mass-produced like newspaper. With further work on cost and stability, Liu envisions applications ranging from medical sensors to green energy systems on Earth — and even power generation in space.

(SD-Agencies)