New efficient lighting device. Part 1. hybrid materials based on inorganic aerogel and metal-organic phosphor

A novel luminescent organic-inorganic hybrid material LightSil (hereinafter referred to as HM-LS) has been fabricated. Tris (8-hydroxyquinolate)aluminum (Alq(3)) purified by vacuum sublimation to 99.999 wt% was used as an organic phosphor. Silica aerogel was used as an inorganic matrix. Alq(3) intercalation into aerogel structure did not strongly influence on the HM-LS morphology characteristics comparing with the pure aerogel, which indicated that the intercalation had proceed on the molecular level. An aerogel based hybrid was supercritical dried in a carbon dioxide environment under a pressure of 120 bar, at 40 degrees C at a carbon dioxide consumption of 500 g/h. The synthesis conditions (TEOS:2-propanol ratio) has been optimized to make the HM-LS sample with the best photoluminescence (PL) characteristics. Analysis of the PL spectra showed that the PL peak maximum of HM-LS shifted to longer wavelengths, and the HM-LS spectrum itself broadened by 64%: FWHMAlq3 = 73 nm, FWHMHM-LS = 113 +/- 3 nm relative to Alq(3) powder PL spectrum. The latter indicated on a change in the electronic structure of Alq(3) in HM-LS in comparison with the nominally pure Alq(3) and this proved the formation of a new hybrid material.

Automated summary

A novel luminescent organic-inorganic hybrid material, HM-LS, has been fabricated by intercalating Alq(3) into a silica aerogel matrix. The optimized synthesis conditions resulted in HM-LS with improved photoluminescence characteristics compared to pure Alq(3).