Europium incorporated in silica matrix obtained by sol-gel: luminescent materials

Abstract

In this work we report some aspects of the chemistry involved in the preparation of modified silicon oxide by the sol-gel process. Europium III compounds were used as luminescent probe. An organic-inorganic hybrid was obtained by hydrolysis of tetraethylorthosilicate (TEOS) and 3-aminopropyltriethoxysilane (APTS). The Eu III compounds were added in different ways. In the first, silica was prepared in the presence of Eu III, and in the second, Eu III was added on the silica surface. These materials were studied by luminescence, infrared spectroscopy and termogravimetric analysis. The results obtained for the hybrid material show different behavior for Eu III emission, which could be excited by the antenna effect and the influence of the surrounding in the luminescence quenching. The thermogravimetric data present different mass loss in samples to range temperature 50 - 150 °C. Thermogravimetric and infrared spectra showed that inorganic polymers incorporated the organic part

The influence of addition of a catalyst and chelating agent on the properties of titanium dioxide synthesized via the sol–gel method

“…A typical sol-gel method is based on hydrolysis and condensation of the precursor (inorganic metal salts or metal organic compounds such as metal alkoxides) [24]. This process can be employed for the synthesis of functionalized inorganic oxides with controlled particle size and shape [35][36][37][38][39][40][41][42]. In the sol-gel method, control of the reactivity of the metal alkoxides used as precursors is very important in order to obtain sols and gels with desirable properties.…”

New synthesis strategies for effective functionalization of kaolinite and saponite with silylating agents

“…The conditions employed in the preparation of these materials depend on the inorganic matrix [15][16][17][18][19][20][21][22][23]. On the other hand, various organofunctional alkoxysilanes have been extensively employed for functionalization of inorganic matrices, such as aminoalkoxysilane [20,[24][25][26], methacrylatealkoxysilane [16,27], glycidylalkoxysilane [9,26], polydimethylsiloxanes [28,29], and others [30][31][32][33]. The so-called silanization process occurs by the reaction between the inorganic matrix and the alkoxysilanes, whose alkoxy groups react with the OH groups present on the surface of the solids producing the hybrid organo-inorganic material after hydrolysis and condensation [34,35].…”

Preparation of a GdCaAl3O7 matrix by the non-hydrolytic sol–gel route

“…The material was synthesized via a modification of the method described by Acosta et al [18,23,37]. AlCl 3 (1.0 g) and ethanol (EtOH 20 ml) were reacted with CaCl 2 (0.276 g), EuCl 3 (2.5 mL), and GdCl 3 (22.5 mL).…”

“…The sol-gel derived glass materials are of great importance because of their countless applications in non-linear optics and optical key, catalysis, solar cells, and chemical and biological sensors [13][14][15]. The main characteristic of the hydrolytic sol-gel process is the formation of stable oxide materials, which have many important applications [15][16][17][18][19][20][21][22][23][24][25][26][27][28].…”