Cadmium sulfide silver nanoplate hybrid structure: Synthesis and fluorescence enhancement

Semiconductor-noble metal hybrid nanostructures are of current interest in the development of bioimaging agents. To enhance photoluminescence of cadmium sulfide nanoparticles via surface plasmon mode coupling, cadmium sulfide conjugated silver nanoplates (denoted as CdS-Ag NP) have been prepared by a forward-reverse cation exchange method. The morphology, crystallinity, and atomic composition of the CdS-Ag NP have been investigated by energy dispersive X-ray spectroscopy and high-resolution transmission electron spectroscopy, and the CdS-Ag NP can be described as Cd²⁺-rich CdS nanoparticles covalently bonded to the surfactant of Ag nanoplates. Photoluminescence enhancement of CdS measured is attributed to the matching between the emission bands of cadmium sulfide and the tailor-made localized surface plasmons resonance bands provided by the Ag NP. Application of the CdS-Ag NP in cell imaging has also been demonstrated.