Nb₂O₅ coating of glass fibres applied by chemical vapour deposition

Abstract

In this study, the chemical vapour deposition (CVD) technique is used to modify the surface of Li 2 O-ZrO 2 -BaO-SiO 2 glass fibre with Nb 2 O 5 , using NbCl 5 as the precursor. Glass fibres were coated as follows: without thermal pretreatment but followed by air exposure after the reaction with NbCl 5 ; without thermal treatment followed by water hydrolysis, with thermal treatment at 300uC for 2 h and air exposure; and finally, with thermal treatment and hydrolysis in water. The best result was obtained with the fibre chemically modified with Nb 2 O 5 after heat treatment followed by water hydrolysis. This procedure resulted in fibres coated with a homogeneous layer of Nb 2 O 5 without cracks. The fibres were characterised by scanning electron microscopy and energy dispersive X-ray spectroscopy. The fibres were evaluated in the qualitative determination of a mixture of methanol, ethanol and 1-butanol by solid phase microextraction and gas chromatography, yielding better results than those of the fibre coated with Nb 2 O 5 prepared by metallo-organic decomposition.

Polymorphs of Nb2O5 Compound and Their Electrical Energy Storage Applications

“…Other studies using the CVD method provide an excellent alternative to the production of layered Nb 2 O 5 , especially for fiber coating applications [114]. For example, Silveira et al exposed glass fiber to air after reacting with NbCl 5 , heat treating at 300 • C for 2 h, and heat treating and hydrolyzing in water to achieve a well-coated glass fiber with Nb 2 O 5 [115].…”

Effect of CVD carbon coatings on properties of SiC fibres

“…As a promising reinforcement for CMCs, the SiC fibre requires an appropriate coating on its surface, because the coatings can weak the interfaces and brings a good fracture mode for the composites. 4 Among the different kinds of interface coating suggested recently, [5][6][7][8][9][10][11][12] carbon is recognised as one of the most commonly used and effective coating materials. For example, the flexural strength of Chemical vapour deposition (CVD) carbon-coated Nicalon SiC fibres reinforced Si-C-O composite was found to be five times higher than that of the uncoated Nicalon SiC fibres reinforced composite.…”

“…Among the different kinds of interface coating suggested recently, 5-12 carbon is recognised as one of the most commonly used and effective coating materials. For example, the flexural strength of Chemical vapour deposition (CVD) carbon-coated Nicalon SiC fibres reinforced Si–C–O composite was found to be five times higher than that of the uncoated Nicalon SiC fibres reinforced composite.…”

Chemically deposited magnesium hydroxide thin film

“…Nowadays, thin films are considered as a highly promising material for biomedical, energy, optical, sensing related applications [1][2][3][4] as well as for corrosion protection of magnesium alloys. [5][6][7][8] In this regard, magnesium oxide is a very important protective material that can be in situ formed from the magnesium hydroxide [Mg(OH) 2 ] thin film 9 precursors.…”