Evolution of Colloidal Plasmonic Heterostructures from Traditional Semiconductor Nanocrystals to Lead Halide Perovskites: A Review

Abstract

Plasmonic heterostructures refer to the class of hybrid nanostructures where two or more nanocrystals (NCs) are chemically bonded, at least one of which is plasmonic. The light concentration property of plasmons is used to manipulate the light−matter interaction in the resulting heterostructures for applications in the fields of nanoscience, photonics, catalysis, and biology among many others. With the advancement of colloidal synthesis, plasmonic heterostructures have a versatile landscape of their own in the last couple of decades. In particular, after the discovery of semiconductor plasmonic NCs (In 2 O 3 , CdO, Cu 2−x S, etc.) and halide perovskite NCs (CsPbX 3 , X: Cl, Br, I), the possibility of heterostructures expanded multifold. Nevertheless, challenges remain in successfully synthesizing phase pure structures, optimizing the right geometry and composition for applications, or more fundamentally, observing plasmonic properties despite the formation of heterostructures. In this Review, we briefly review the progress of the colloidal plasmonic heterostructures in terms of synthesis, optical properties, and applications. We discuss these aspects in the traditional noble metal nanoparticle-based compounds, followed by semiconductor plasmonic and halide perovskite heterostructures. We specifically focus on the current challenges faced by the research community in the field of plasmonic halide perovskites and how fundamental design principles can bypass the current limitations.