Luminous, Self-Powered 3D Skins for Underwater Communication

A team of researchers at the National University of Singapore has successfully 3D printed an elastic “photonic skin” capable of generating light without the need for batteries or cables. Thanks to an auxetic design, meaning it expands when stretched rather than contracting, this technology promises to improve communication and safety in underwater environments, from recreational diving to robotic exploration in deep waters.

Underwater exploration remains a challenge. Low visibility, salinity and extreme temperatures damage conventional electronic devices. Although LEDs and optical fibers are used in some equipment, their dependence on external power sources and limited flexibility reduces their usefulness in dynamic conditions. The new approach combines mechanoluminescence, the ability of certain materials to emit light when stretched or pressed, with 3D printing of auxetic structures. The result is a material that glows when moved and adapts to curved surfaces such as gloves, air tanks or even soft robots.

Auxetic structures adapt to curved surfaces, are elastic, shiny and have exceptional durability even in adverse conditions, enabling reliable exploration in deep waters.

3D Printing and Auxetic Materials

The team printed ZnS (zinc sulfide) cellular structures in a silicone matrix. This compound is stable, biocompatible, and safe for marine environments. In this way, the auxetic design improves the material’s adaptability to complex geometries. An outer layer of silicone distributes stress more evenly, ensuring uniform luminosity even under repeated stretching. According to the experiments, the photonic skin maintained its performance after more than 10,000 cycles of use, demonstrating remarkable durability for demanding applications.