Dependence of the refractive index of transparent ZrO2–SiO2 aerogels on the density and zirconium content.

In this work ZrO 2 –SiO 2 aerogels with ZrO 2 content of 3, 6 and 10 mol. % in the form of transparent blocks were synthesized using the sol-gel method. The possibility of introducing ZrO 2 into a SiO 2 aerogel without considerable decline of the optical characteristics of the material was shown for the first time. Aerogel samples were studied by several techniques including UV–Vis, ATR-FTIR spectroscopy and nitrogen adsorption, the refractive index was determined using beam tests ("Extracted beams" of the VEPP-4M complex). It was shown that the addition of ZrO 2 to SiO 2 aerogel increases the refractive index without increasing of the aerogel density. For the first time, the possibility of obtaining highly transparent ZrO 2 –SiO 2 aerogel blocks with acceptable optical characteristics for radiator in Cherenkov detectors has been demonstrated. This result makes it possible to achieve high refractive indices in the production of aerogel blocks for Cherenkov detectors to increase their performance. [ABSTRACT FROM AUTHOR]