A Flexible ZnO Nanowire-Based Humidity Sensor

In this paper, the authors report the direct growth of ZnO nanowires (NWs) on a flexible substrate by the hydrothermal process and the fabrication of ZnO NW-based humidity sensor. It was found that average length and diameter of the ZnO NWs were 0.6 μm and 50 nm, respectively. It was also found that resistance of the ZnO NWs decreased by 45% as we increased the relative humidity from 52% to 90%. Furthermore, it was found that measured resistance was very stable with negligible fluctuation after 16 days continuous testing.