Pd-decorated Si nano-horns as sensitive and selective hydrogen gas sensors

The semiconductor industry is based mainly on silicon (Si). Therefore, gas sensors based on Si that have high compatibility with semiconductor technology are among the most promising sensing devices. This study examined the effects of the sensing temperature, selectivity, and detection limits for real applications. This paper reports highly selective hydrogen gas sensors fabricated from Pd-decorated Si nano-horns (NHs). First, Si-NHs were prepared using a simple chemical etching method, which was followed by Pd-decoration using a UV irradiation technique. Electrical and gas sensing measurements showed that the resistance of the gas sensors was affected considerably by the sensing temperature as well as the size of the Pd nanoparticles (NPs). Furthermore, the optimized gas sensor could detect as little as 0.1 ppm H-2 gas. The present sensors with exceptional performance toward hydrogen gas have potential use as Si-based hydrogen gas sensors.