Gallium-indium liquid metal self-healing electronics - Part 3

Jim: Eric, at first blush your work with self-healing electronics seems more like magic than science. From what I gather, you use a plotter to rupture the liquid metal cell walls and interconnect them within the elastomer, could you explain the principle around how this works?

Eric: Yeah, it's definitely mysterious and quite different from what has been previously shown in literature. The secret behind our 'magic trick' is the unique material architecture. Interestingly, when pressed with sufficient local pressure, the embedded microscopic droplets rupture, transforming the rubber from an insulator to an electrical conductor. Upon further investigation, we found that this instantaneous transformation also occurred during other forms of material damage including cutting, tearing, and puncture. 

Writing a soft circuit using a pen plotter: check out the video here.

Jim: Can this be done by hand?

Eric: Yes, circuits can be created by applying sufficient local pressure. This can be accomplished by a variety of methods such as drawing on the material with a ball point pen or a cotton tipped applicator. We use the commercially available XY pen plotter for consistency during characterisation and to enable complex geometric patterns to be created. 

Now that we have learned a little about the material and how it works, in the next post we will talk about what applications we could use this technology for.

(The electrically self-healing liquid metal-elastomer composite is detailed in Nature Materials)