Spirobenzopyran-based photochromic nanohybrids with photoswitchable fluorescence

The preparation and performance characterization of about 40 nm spirobenzopyran-based photochromic nanohybrids with photoswitchable fluorescence are presented. The nanohybrids were fabricated by means of a modified miniemulsion polymerization process, in which hydrophobic spirobenzopyran and the matched fluorescent dyes are intermolecularly hybridized and embedded in the nanoscale crosslinked polymeric matrix. The obtained nanohybrids with high relative fluorescence quantum yield (Q) exhibited superior fluorescent photoswitchable performance due to the effective photoinduced intermolecular energy transfer, and also the thermal stability of photomerocyanine was improved.