Recent advances and applications of ionic liquids-based photonic materials

Beyond the traditional applications as electrolytes and solvents, ionic liquids (ILs) have emerged as building blocks or components of various advanced functional photonic materials. ILs as a platform give a chance to modify the physicochemical properties of materials for the intended applications because of their unique properties and structural varieties. These also offer some fascinating features due to the synergetic interaction among the ionic components. Beyond the traditional use of ILs, the active research field has recently triggered several novel photonic materials for versatile advanced optoelectronic applications. In the last few decades, it stimulated advanced applications in photon upconversion, white light generation, bioimaging, sensing, nonlinear optics, etc. An overview of ILs-based photonic materials, including their mechanism, primary material systems, and how they are used in diverse applications with merits and demerits, are also discussed in this review. Some potential directions are also out looked to explore this emerging research topic. We anticipate that this article will enable researchers to quickly access the most current knowledge in the fast-expanding field of ILs-based photonic materials. This will also pave the way for researchers to plan and fabricate new ILs-based photonic materials for versatile applications.