Dual Plasmonic Au-Cu_2-x S Nanocomposites: Design Strategies and Photothermal Properties

Coupling two different materials to create a hybrid nanostructured system is a powerful strategy for achieving synergistically enhanced properties and advanced functionalities. In the case of Au and Cu_2-x S, their combination on the nanoscale results in dual plasmonic Au-Cu_2-x S nanocomposites that exhibit intense photon absorption in both the visible and the near-infrared spectral ranges. Their strong light-absorbing properties translate to superior photothermal transduction efficiency, making them attractive in photothermal-based applications. There are several nanostructure configurations that are possible for the Au-Cu_2-x S system, and the successful fabrication of a particular architecture often requires a carefully planned synthetic strategy. In this Minireview, the different synthetic approaches that can be employed to produce rationally designed Au-Cu_2-x S nanocomposites are presented, with a focus on the experimental protocols that can lead to heterodimer, core-shell, reverse core-shell, and yolk-shell configurations. The photothermal behavior of these materials is also discussed, providing a glimpse of their potential use as photothermally active agents in therapeutic and theranostic applications.