Ternary Hybrid Nanostructures of Au-CdS-ZnO Grown via a Solution-Liquid-Solid Route Using Au-ZnO Catalysts

Hybrid nanostructures have been the focus of many researches in recent years due to their unique properties. These heterostructures commonly possess multifunctionality and in some cases there is a synergy between their different components that leads to enhanced, and even novel, properties. Currently, the most common strategy for the synthesis of such heterostructures is a multistep seeded growth that is based on heterogeneous nucleation of the nanostructure components. While this method enabled the synthesis of a wide range of heterostructures, it is still constrained by surface chemistry considerations that limit the material combinations, morphologies, and configurations that can be attained. It is therefore important to find additional synthetic strategies that can improve the control over such features. In our work we succeeded to synthesize Au-CdS-ZnO hybrid nanostructures by a non-conventional strategy that combines two different synthetic approaches: seeded growth and solution-liquid-solid (SLS) growth. Each of these synthetic routes is used for growing a different domain of the final heterostructure, where ZnO rods are grown first on Au nanoparticles via heterogeneous nucleation while CdS is later grown between these two domains via SLS, using the Au tip of the preformed Au-ZnO as a catalyst. Such combination of synthetic approaches for the formation of hybrid nanostructures have the potential for achieving novel material compositions and configurations and therefore can contribute to expanding the variety of these systems and increasing their complexity.