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Relevance of sol–gel transition and spinodal decomposition for hierarchical porosity structure of monolithic alumina
(2021-01-01)
In situ techniques were used to investigate the hierarchical porous structure of alumina monoliths formed by the combined processes of sol–gel transition and spinodal phase separation. The addition of low molecular weight ...
Broadband NIR emission in novel sol-gel Er3+-doped SiO 2-Nb2O5 glass ceramic planar waveguides for photonic applications
(2013-01-01)
This paper reports on the sol-gel preparation and structural and optical characterization of new Er3+-doped SiO2-Nb 2O5 nanocomposite planar waveguides. Erbium-doped (100-x)SiO2-xNb2O5 waveguides were deposited on ...
Evolution of the fractal structure during sintering of SnO2 compacted sol-gel powder
(1995-04-28)
The structural evolution during sintering of compacted SnO2 sol-gel powder was investigated using nitrogen adsorption isotherm analysis. Results show that for sintering temperatures up to 400°C the samples have a fractal ...
A surface modification for hydrogen storage intermetallic particles by sol-gel method
(2001-12-01)
A new process for the surface modification of hydrogen storage intermetallic particles used as anode material in secondary batteries is proposed in this article. The copper oxide particles coverage obtained by the sol-gel ...
Influência da catálise ácida e básica na preparação da sílica funcionalizada pelo método sol-gel
(Sociedade Brasileira de Química, 2002-02-01)
Some aspects of the chemistry involved in the preparation and characterization of functionalized silicon oxide by sol-gel method are considered in this work. The synthesis was performed with different silicon alcoxide ...
Ultraviolet excitation of photoconductivity in thin films of sol-gel SnO2
(Elsevier B.V., 2005-01-01)
Tin dioxide (SnO2) thin film photoconductivity spectra were measured for a large temperature range using a deuterium source, the intensity of photocurrent spectra in the range 200-400 nm is temperature dependent, and the ...
Zirconia foams prepared by integration of the sol-gel method and dual soft template techniques
(Elsevier B.V., 2008-11-01)
This paper presents a new method to produce basic zirconium sulfate foams showing hierarchic porosity, based on a dual pores templating process by oil drops and gas bubbles dispersed into a hydrosol, followed by its fast ...
Europium incorporated in silica matrix obtained by sol-gel: luminescent materials
(ABM, ABC, ABPol, 2003-12)
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 ...
Er rare-earth ion incorporation in sol-gel SnO2
(ABM, ABC, ABPol, 2003-12)
Er-doped SnO2 thin films and xerogels are obtained by sol-gel technique. In order to understand the Er³+ rare-earth ion activity in SnO2 matrix, a characterization of Er incorporation is done through emission and excitation ...