Three-Dimensional Continuous Conductive Nanostructure\nfor Highly Sensitive and Stretchable Strain Sensor

Abstract

The demand for wearable\nstrain gauges that can detect dynamic human motions is growing in\nthe area of healthcare technology. However, the realization of efficient\nsensing materials for effective detection of human motions in daily\nlife is technically challenging due to the absence of the optimally\ndesigned electrode. Here, we propose a novel concept for overcoming\nthe intrinsic limits of conventional strain sensors based on planar\nelectrodes by developing highly periodic and three-dimensional (3D)\nbicontinuous nanoporous electrodes. We create a 3D bicontinuous nanoporous\nelectrode by constructing conductive percolation networks along the\nsurface of porous 3D nanostructured poly­(dimethylsiloxane) with single-walled\ncarbon nanotubes. The 3D structural platform allows fabrication of\na strain sensor with robust properties such as a gauge factor of up\nto 134 at a tensile strain of 40%, a widened detection range of up\nto 160%, and a cyclic property of over 1000 cycles. Collectively,\nthis study provides new design opportunities for a highly efficient\nsensing system that finely captures human motions, including phonations\nand joint movements.