| 초록 |
We demonstrate a novel type of stretchable strain sensor including piezoelectric zinc oxide (ZnO) nanocrystals grown on flexible curved filaments or flat film surfaces to monitor human motions with wide ranges of strains (up to 50%). Crystal growth and development of ZnO can be controlled with (1) areal density of ZnO nano-seeds pre-mounted on substrates, (2) hydrothermal process conditions such as precursor concentration, time, and temperature, (3) physicochemical characteristics of the seeding surfaces. Crystalline structures of ZnO nanoarrays grown on supporting surfaces are systematically investigated by grazing-incidence X-ray scattering/diffraction and morphological analyses. It is found that the crystals grown on polymer or metal surfaces can be controlled with preferred shapes, sizes, and orientations. An optimized strain sensor including ZnO nanowires on polymer surfaces can be operated at high strain (up to 50%), with high durability, fast response, and high gauge factors. |
