1. Introduction
Structural colors have attracted conspicuous interest due to their fascinating potential in the applications of sensors, optical data storage, information encryption, and display devices. Now, vivid structural colors can be generated through the interaction of light with periodic structures—most of their period () is comparable to the light wavelength[1–3]. Although as frequently suggested that the structural colored materials show superior stability compared with the colored chemical dyes and pigments, their stability at high temperature (e.g., ) is intrinsically poor due to the large surface area of the sub-micrometer structures. Furthermore, nearly all of the current structural colors materials are built on substrates with the surface exposed to the environment, and this is inevitably detrimental to the structure stability. Stable structural colors at high temperature will be critical for storing the information for a long time[4]. Various techniques have been developed to fabricate desirable periodic structures for modulating the light field and producing structural colors, such as self-assembly and nanolithography[5–14]. However, complicated procedures are generally needed in most of the traditional fabrication methods, and limited scalability and lack of robustness still remain major challenges for the real-world applications.