Sandwich-like Cu1.94S–ZnS–Cu1.94S nanoheterostructure: structure, formation mechanism and localized surface plasmon resonance behavior

In this communication, a thermolysis route is developed to synthesize novel Cu1.94S–ZnS–Cu1.94S nanoheterostructures with interesting sandwich-like architectures, taking Cu1.94S nanoplates as precursors. Evidently, the trimeric nanostructure is formed by a three-stage process, which includes the Zn-oleate induced assembling of Cu1.94S nanoplate couples, the heteronucleation and growth of a ZnS layer between two Cu1.94S plates dominated by interfacial diffusion, and the catalyst assisted axial growth of ZnS nanorod following the solution–liquid–solid mechanism. With epitaxial growth of ZnS nanocrystal between two Cu1.94S nanoplates, the localized surface plasmon resonance frequency of Cu1.94S shifts from 1875 to 1323 nm, indicating that this new material is potentially applicable as a light absorbing agent in laser photothermal therapy. The reported growth mechanism may provide new strategies for designing and fabricating various technologically important polymeric nanoheterostructures. (paper)