Controlling Circularly Polarized Luminescence Using Helically Structured Chiral Silica as a Nanosized Fused Quartz Cell

Abstract

Circularly polarized luminescence (CPL) is typically achieved with a chiral luminophore. However, using a helical nanosized fused quartz cell consisting of chiral silica, we could control the wavelength and helical sense of the CPL of an achiral luminophore. Chiral silica with a helical nanostructure was prepared by calcining a mixture of polyhedral oligomeric silsesquioxane (POSS)-functionalized isotactic poly(methacrylate) (it-PMAPOSS) and a small amount of chiral dopant. The chiral silica encapsulated functional molecules, including luminophores, along the helical nanocavity, leading to induced circular dichroism (ICD) and induced circularly polarized luminescence (iCPL). Because chiral silica can act as a helical nanosized fused quartz cell, it can encapsulate not only the luminophore but also solvent molecules. By changing the solvent in the luminophore-containing nanosized fused quartz cell, the wavelength of the CPL was controlled. This method provides an effective strategy for designing novel CPL-active materials.

Chiral Transfer of Linear Polysiloxane with Preferred-Handed Helical Conformation

“…We reported the preparation of POSS-functionalized polymethacrylate with isotactic configuration ( it -PMAPOSS) using anionic polymerization. it -PMAPOSS forms preferred-handed helical conformation when mixed with a small amount of chiral dopant, and the helical conformation can be kept during the calcination process, leading to a chiral silica. , Moreover, the chiral silica acts as a fused-quartz nanocell, and it encapsulates a luminophore in the helical nanocavity, leading to a circularly polarized luminescence (CPL) . However, these approaches require the use of moisture-sensitive TEOS or non-cost-effective POSS.…”