Sensitive Room Temperature Photoluminescence-Based Sensing of H₂S with Novel CuO–ZnO Nanorods

Novel CuO nanoparticle-capped ZnO nanorods have been produced using a pulsed laser deposition (PLD) method. These nanorods are shown to grow by a CuO–nanoparticle-assisted vapor–solid–solid (V–S–S) mechanism. The photoluminescence (PL) accompanying ultraviolet illumination of these capped nanorod samples shows large variations upon exposure to trace quantities of H₂S gas. The present data suggest that both the Cu-doped ZnO stem and the CuO capping nanoparticle contribute to optical H₂S sensing with these CuO–ZnO nanorods. This study represents the first demonstration of PL-based H₂S gas sensing, at room temperature, with sub-ppm sensitivity. It also opens the way to producing CuO–ZnO nanorods by a V-S-S mechanism using gas-phase methods other than PLD