A facile route to silver–cadmium sulfide core–shell nanoparticles and their nonlinear optical properties

• Ag@CdS core–shell nanoparticles were synthesized by a reversed micelle method.
• The CSNPs were found to exhibit an obvious nonlinear response at room temperature.
• The refraction index of the CSNPs increase ten times as that of pure CdS NPs.

The synthesis of silver–cadmium sulfide core–shell nanoparticles (Ag@CdS CSNPs) with positional and morphological control still remains a challenge because of the large lattice mismatch between the two components. In this paper, Ag@CdS CSNPs with controllable core morphology and shell thickness were synthesized by using a reversed micelle method. Z-scan measurements show that the synthesized CSNPs exhibit an obvious nonlinear response at room temperature. Both the nonlinear absorption coefficient and refraction index of the CSNPs increase tens of times as those of the pure CdS shell counterparts, which result from the large local field enhancement of localized surface plasmon of cubic Ag core.