Ultrastretchable Hybrid Electrodes of Silver Nanowires and Multiwalled Carbon Nanotubes Realized by Capillary- Force-Induced Welding

The paucity of soft materials with both high electrical conductivity and the capability to maintain their superior conductance under large and complex mechanical deformations is a crucial barrier hindering the development of stretchable electronics toward practical applications. A type of ultrastretchable hybrid electrodes composed of silver nanowires (AgNWs) and multiwalled carbon nanotubes (CNTs) are reported, which show sheet resistance as low as 7.1 omega sq.(-1) and a small resistance increase of only 42% when uniaxially stretched to a strain of 580%. The hybrid electrodes can also withstand equibiaxial stretching, showing a resistance increase of 100% at a strain of 200%, and survive at least 1500 stretching/releasing cycles with negligible resistance change. The key to such performance is welding the loosely stacked AgNWs and CNTs into one integrated network with the aid of capillary force. When coated onto both sides of a polyacrylate-based elastomer, VHB, the AgNW/CNT hybrid films can serve as excellent compliant electrodes of a dielectric elastomer actuator, causing a maximum actuated areal strain of 190% with a relatively low starting electric field of 11.6 V mu m(-1). These ultrastretchable AgNW/CNT electrodes will pave the way for the rapid development of high-end stretchable electronics.