Core-Shell Micro- and Nano-Structures for The Modification of Light-Surface Interactions

Controlling how a material interacts with light is key to optimizing its optical properties to fit a desired function or application. The most straightforward approach is to chemically or physically modify the surface exposed to incident light. An effective method of surface modification is based on the addition of core-shell structures at the surface. Of particular importance to many technological applications are core-shell structures with dimensions comparable to the wavelengths of light extending from the UV up to the near-IR region of the electromagnetic spectrum, which coincides with the major part of the solar spectrum. Surface modification approaches to tailor the optical properties of materials in this range of wavelengths are increasingly relevant in the context of materials and devices used in sustainable energy applications, such as solar cells and heat-reflective paints. These materials are useful to mitigate the current energy and climate crises by allowing for enhanced energy harvesting and improved thermal management, respectively. Here, recent progress in the fabrication and application of core-shell micro-/nano-structures for the modification of light interaction with surfaces is highlighted. Some limitations and future directions for the design of core-shell materials are also discussed. Surfaces modified with hybrid core-shell micro-/nano-structures can strongly interact with incident light and thereby influence the material's optical properties. This review summarizes recent progress in the preparation of core-shell micro-/nano-structures for reflective, anti-reflective and stimuli-responsive applications, with the goal of enhancing the optical performance. The core-shell design strategies and fabrication methods are discussed in relation to the desired application.image