Novel electrically-conductive electro-responsive hydrogels for smart actuators with a carbon-nanotube-enriched three-dimensional conductive network and a physical-phase-type three-dimensional interpenetrating network

Abstract

Electro-responsive hydrogels have already drawn increasing attention for their promising industrial applications. High application performance such as fast electrical response and excellent mechanical properties still remains a great challenge for electro-responsive hydrogels to date. Herein, a hydrogel with a carbon-nanotube-enriched (CNT-enriched) conductive network and a physical-phase-type interpenetrating network was constructed for the first time with the help of nickel foam in consideration of its unique three-dimensional macro-pore network. The contribution of the CNT-enriched network to the electrical conductivity and electro-response of a P(AMPS-co-AA)-based composite hydrogel was focused on. Due to the three-dimensional CNT-enriched conductive network, our targeted hydrogels show outstanding electrically-conductive performance with an electrical conductivity of up to 1.82 × 10⁻² S cm⁻¹. The effect of the CNT-enriched network on the swelling performance and electro-responsive rate is discussed, and it is confirmed that the existence of the CNT-enriched network is beneficial to accelerating the electro-response. Our innovative unique microstructure hopefully becomes a significant variable strategy to design various high-performance hydrogels.