Article ID: M2016026
In this work, the facile synthesis of Ag/CuInS2 composite nanoparticles (NPs) with a core-shell structure is demonstrated for the first time. In our procedure, the pre-formed Ag NPs were subsequently coated with a CuInS2 shell through the thermal decomposition of the metal thiolate complex. The Ag/CuInS2 composite NPs took Ag core-CuInS2 shell structures (Ag@CuInS2) when an oleic acid-oleylamine mixture was used as the co-surfactant. High-resolution transmission electron microscopy (TEM) indicated the epitaxial growth of the CuInS2 shell on the Ag NPs. In the extinction spectrum of the Ag@CuInS2 NPs, the localized surface plasmon resonance (LSPR) peak of the Ag core broadened and red-shifted to 2.21 eV, confirming that the LSPR can be tuned by the CuInS2 shell. Finite-difference time-domain (FDTD) simulations indicated the enhancement of the electric field in the CuInS2 shell region and the surface of the Ag@CuInS2 NPs. This enhancement effect may improve the efficiency of incident light absorption in CuInS2 quantum dot sensitized solar cells.