Polydopamine-based photonic crystal structures

Abstract

Active photonic crystals (PC) or photonic crystal heterostructures have many applications such as chemical and biological sensors, active colour displays, structural colour printing and fluorescence enhancement. However, photonic crystal structures with the different functions mentioned above require different preparation methods, and some of them require sophisticated instruments for specific production processes. Thus, development of a simple way or a useful platform for conveniently fabricating specific photonic crystal structures with different functions is highly desirable and significant. Herein, by exploiting the self-polymerization of dopamine, we successfully introduced polydopamine (PDA) into silica opaline templates and produced PDA photonic crystal structures. Based on the utilization of the unique properties of PDA such as reactivity, reductive ability, powerful adhesive capability as well as carbonizable feature, PDA-based photonic crystal structures provide a very useful platform for further convenient fabrication of multifunctional photonic crystal structures with a variety of potential applications. Due to the virtually unlimited variety provided by the active secondary reactions of PDA, the post-modification of PDA-based photonic crystals can readily afford photonic crystal based chemical or biological sensors. The reductive as well as adhesive ability of PDA provides another tremendous opportunity to produce photonic crystal heterostructures with various metals, metal oxides, polymer or semiconductor nanoparticles. As a demonstration, PDA/Ag/PDA and PDA/Pt/PDA opaline structures were prepared by PDA-assisted metallization or adsorption, respectively, which could find promising application in fluorescence enhancement of organic dyes or chemical solvent sensors. More importantly, the carbonizable feature of PDA allows for efficiently producing carbon inverse opaline films as well as metal particle doped carbon inverse opaline films by carbonizing the corresponding PDA, PDA/Ag/PDA or PDA/Pt/PDA photonic structures, which may show various potential applications in catalysis and energy conversion.