Enhancing the UV Emission in ZnO-CNT Hybrid Nanostructures via the Surface Plasmon Resonance of Ag Nanoparticles

The crystal quality and surface states are two major factors that determine optical properties of ZnO nanoparticles (NPs) synthesized through nonaqueous sol-gel routes, and both are strongly dependent on the growth conditions. In this work, we investigate the influence of the different growth temperatures (240 and 300 degrees C) on the morphology, structural and crystal properties of ZnO NP. The effects of conjoining ZnO NP with carbon nanotubes (CNT) and the role of surface states in such a hybrid nanostructure are studied by optical emission and absorption spectroscopy. We demonstrate that depending on the synthesis conditions, activation or passivation of certain surface states may occur. Next, silver nanoparticles are incorporated into ZnO-CNT nanostructures to explore the plasmon-exciton coupling effect. The observed enhanced excitonic and suppressed defect-related emissions along with blue-shifted optical band gap suggest an intricate interaction of Burstein-Moss, surface plasmon resonance and surface band-bending effects behind the optical phenomena in hybrid ZnO-CNT-Ag nanocomposites.

Automated summary

The study investigated the effects of different growth temperatures on the morphology, structure, and crystal properties of ZnO nanoparticles, as well as the optical properties of hybrid ZnO-CNT-Ag nanocomposites. The research demonstrated that under different synthesis conditions, activation or passivation of certain surface states may occur, leading to complex interactions of optical phenomena in the nanocomposites.