Extended functionality of ZnO nanotetrapods by solution-based coupling with CdS nanoparticles

Coupled nanostructures with "spotted" and "core-shell" morphologies have been obtained by a controlled heterogeneous nucleation of cadmium sulfide nanoparticles (CdS-NPs) onto the surface of zinc oxide nanotetrapods (ZnO-TPs). This result has been obtained by means of a modified chemical bath deposition reaction, without the need of any surfactant and surface passivating agents. The coupled nanostructure has been demonstrated to form an active p-n type-II heterojunction, clearly affecting the functional properties of ZnO nanostructures, as in gas-sensing or photocatalysis applications.