초록 |
Triplet-triplet annihilation upconversion(TTA-UC) is a photochemical process wherein two or more low-energy photons are converted to a high-energy photon through special energy transfer mechanism. Herein, we report a strategy to enhance the efficiency of TTA-UC through light-scattering effect induced by silica microparticles(SM) embedded in polymeric films. By incorporating monodisperse uniform silica microparticles of 950 nm, which were synthesized by Stöber-based seeded growth method, into UC polymeric films, the UC intensity in the 430–570 nm was enhanced by as much as 64% when irradiated by 635 nm laser. Incorporation of SM in UC layer is shown to enhance the triplet-triplet annihilation(TTA) efficiency, which results in 1.5-fold increase of the ΦUC, by scattering light source and thus increasing the number of excited photons to be utilized in TTA-UC process. |