Functionalization of selectively grown networked SnO2 nanowires with Pd nanodots by γ-ray radiolysis

gamma-ray radiolysis is applied to synthesizing Pd nanodots on networked SnO2 nanowires. The growth behavior of Pd nanodots is systematically investigated as a function of the precursor concentration, illumination intensity, and exposure time of the gamma-rays. These factors greatly influence the growth behavior of the Pd nanodots. Selectively grown networked SnO2 nanowires are uniformly functionalized with Pd nanodots by the radiolysis process. The NO2 sensing characteristics of the Pd-functionalized SnO2 nanowires are compared with those of bare SnO2 nanowires. The results indicate that gamma-ray radiolysis is an attractive means of functionalizing the surface of oxide nanowires with catalytic Pd nanodots. Moreover, the Pd-functionalization greatly enhances the sensitivity and response time in SnO2 nanowire-based gas sensors.