Silver nanowire: Synthesis, conductivity improvement and application to pressure sensor

Silver nanowires (AgNWs) are synthesized with various lengths and diameters depending on the reaction parameters and the stirring speed in polyol process. AgNWs > 80 μm in length are prepared at 110 °C without stirring, while shorter wires with only 20~30 μm even below 5 μm become the main products at reaction temperature from 160 to 200 °C. These AgNWs are then simply washed with several solvents in order to decrease the thickness of PVP layer adsorbed on the surface of wires to achieve low contact resistivity between the wires. Transparent electrodes based these silver nanowire with low sheet resistance of 10 Ω/□ and high transmittance of 85% are achieved and further applied to flexible transparent pressure sensor with a rapid correspond from 0 nF to finite value depending on the compressive stress applied, showing excellent repeatable and stable response sensitivity.