Sweat it Out!

Bulb light on

America runs on…sweat?

This is Sandra Tsing Loh with the Loh Down on Science.

A morning run – so invigorating! The feeling of sweat rolling down your back? Yuck! But can sweat be useful?

Xueping Zhang and colleagues from the National University of Singapore had a “dry idea!”

The team experimented with Cobalt-SHM a super absorbent material that contains cobalt metal. First, they made a thin layer the width of a hair. Then, they added it to armpit pads and shoe liners to collect sweat.

Lightbulb moment! Why not convert sweat into electricity? The researchers connected an electrical cell to the pad and plugged a small light bulb into the cell. Then, they took a run! When the sweat interacted with the Cobalt-SHM in the cell – eureka!

The electricity from the collected moisture turned on the light after just ten minutes of running! Sunlight reactivates the material so it can be reused.

Athletes, rejoice! Zhang thinks the electricity from sweat could eventually power wearable devices. Now that’s what I call a sweaty, but sweet solution!

Now go, run, and sweat there be light!

Reference: Zhang, X., Yang, J., Borayek, R., Qu, H., Nandakumar, D. K., Zhang, Q., Ding, J. Tan, S. C. Super-hygroscopic film for wearables with dual functions of expediting sweat evaporation and energy harvesting. Nano Energy 75, 104873 (2020). https://doi.org/10.1016/j.nanoen.2020.104873