Sticky gecko-inspired material conducts electricity

A new take on adhesives inspired by sticky gecko feet has led to stretchy silicone patches that conduct electricity and cling fast to skin, even underwater (ACS Nano 2016, DOI: 10.1021/acsnano.6b01355). The material could be used as comfortable, low-cost, reusable electrodes for heart monitors, fitness sensors, or wearable electronics. A team led by materials scientist Seokwoo Jeon of the Korea Advanced Institute of Science & Technology (KAIST) mixed conductive carbon nanotubes and graphene nanopowder into polydimethylsiloxane and poured the composite into a silicon mold dotted with holes. After curing the elastomer at 120 °C for two hours, they had a 10- by 10-cm square patch covered with 15-µm-tall golf-tee-shaped pillars. These shapes mimic the microscopic, hairlike features on gecko feet that can cling to surfaces via van der Waals interactions. When a volunteer wore the patch wired to an electrocardiography recorder, the team measured heartbeat signals that matched those from a commercial electrode. What’s more, the patch conducted signals when attached to an arm submerged in water, whereas the commercial electrode came off within five seconds.