An enhanced gas ionization sensor from Y-doped vertically aligned conductive ZnO nanorods

A stable and highly sensitive gas ionization sensor (GIS) constructed from vertically aligned, conductive yttrium–doped ZnO nanorod (YZO NR) arrays is demonstrated. The conductive YZO NRs are synthesized using a facile one-pot hydrothermal method. At higher Y/Zn molar ratio, the aspect ratio of the YZO NRs is increased from 11 to 25. Doping with yttrium atoms decreases the electrical resistivity of ZnO NRs more than 100 fold. GIS measurements reveal a 6-fold enhancement in the sensitivity accompanied with a significant reduction in breakdown voltage from the highly conductive YZO NRs. Direct correlations between the resistivity of the NRs and GIS characteristics are established