Research & Reviews: Journal of Material Sciences
MenuISSN:2321-6212
ISSN:2321-6212
Dimitar Shandurkov, Nina Danchova and Denis Paskalev, and Stoyan Gutzov
Sofia University St. Kliment Ohridski, Bulgaria
Posters & Accepted Abstracts: Res. Rev. J Mat. Sci
Sol-gel technology is an advanced physico-chemical method for production of oxide ceramics, glasses, thin film coatings or aerogels. The starting chemicals /liquid precursors as tetraethoxysilane � TEOS/ allow homogenization at molecular level, production of rare chemical compositions and modification of their surface properties [1 - 5]. Aerogels are advanced solid sol-gel materials with extremely low thermal conductivity down to 0.01 W/m K; low density (bellow 0.1 g / cm3) and porosity at about 95%. There are two general strategies for preparation of aerogel particles depending on drying conditions, supercritical and subcritical drying [1, 2]. In the Department of Physical Chemistry, University of Sofia, a novel subcritical preparation scheme based on controlled drying at 0.2-0.5 atm and 40-70 oC was developed. The sol-gel scheme allows preparation both of aerogel microgranules and nanopowders. Recently, we also developed a new technique for incorporation of strongly red emitting complexes / Eu(III) phenanthroline nitrate / into silica aerogels leading to multicolour emiting powders [1, 2]. The technique was also applied to incorporate [Tb(phen)2](NO3)3 and Eu(III) � DMF complexes into aerogel powders. Physicochemical properties of the powders obtained are shown bellow, SBET and Dav are surface area and mean pore diameter, respectively. Cabot Lumira� aerogel granules (sample 5) are given for comparison.Recent Publications: 1. S. Gutzov, N. Danchova, S. I. Karakashev, M. Khristov, J. Ivanova, J. Ulbikas, Preparation and thermal properties of chemically prepared nanoporous silica aerogels, J Sol-Gel Sci Technol 70 (2014) 511-516. 2. S. Gutzov, N. Danchova, R. Kirilova, V. Petrov, S. Yordanova, Preparation and luminescence of silica aerogel composites containing an europium (III) phenanthroline nitrate complex, Journal of Luminescence 183 (2017) 108�112. 3. J.C.G. Bunzli, On the design of highly luminescent lanthanide complexes, Coordin Chem Rev 293 (2015) 19-47. 4. Preparation and spectral properties of europium hudrogensquarate microcrystals, T. Kolev, N. Danchova, D, Shandurkov, S. Gutzov, submitted to Spectrochimica Acta A (2017) 5. N. Danchova, S. Gutzov, Functionalization of Sol-Gel Zirconia Composites with Europium Complexes, Z Naturforsch B 69(2) (2014) 224-230.
Dimitar Shandurkov studies Physical and theoretical chemistry at the Faculty of Chemistry and Pharmacy, Sofia University “St. Kliment Ohridski”. He possess experience in the sol-get chemistry, hybrid optical materials, obtained at the Department of Physical Chemistry. In addition, he has a strong background in computational chemistry and applied mathematics.
Email:dimitar.shandurkov@gmail.com