Development of Single-Crystal α-Al2O3 Fibers by Vapor-Liquid-Solid Deposition (VLS) from Aluminum and Powdered Silica

Valcárcel, Víctor; Souto, Alejandro; Guitián, Francisco

doi:10.1002/(sici)1521-4095(199801)10:2<138::aid-adma138>3.0.co;2-a

Cited by 103 publications

(45 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1−3 Various bottom-up approachessuch as vapor− liquid−solid (VLS) 4 and vapor−solid (VS) 5 growthand topdown techniquessuch as nanocarving 6 and electrospinning 7 have been described. Among these techniques, electrospinning is probably the most versatile, because it allows the fabrication of fibrous mats from a wide variety of both organic and/or inorganic materials.…”

Section: ■ Introductionmentioning

confidence: 99%

Hierarchically Structured Metal Oxide/Silica Nanofibers by Colloid Electrospinning

Horzum

Muñoz‐Espí

Glaßer

et al. 2012

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

We present herein a new concept for the preparation of nanofibrous metal oxides based on the simultaneous electrospinning of metal oxide precursors and silica nanoparticles. Precursor fibers are prepared by electrospinning silica nanoparticles (20 nm in diameter) dispersed in an aqueous solution of poly(acrylic acid) and metal salts. Upon calcination in air, the poly(acrylic acid) matrix is removed, the silica nanoparticles are cemented, and nanocrystalline metal oxide particles of 4−14 nm are nucleated at the surface of the silica nanoparticles. The obtained continuous silica fibers act as a structural framework for metal oxide nanoparticles and show improved mechanical integrity compared to the neat metal oxide fibers. The hierarchically nanostructured materials are promising for catalysis applications, as demonstrated by the successful degradation of a model dye in the presence of the fibers. KEYWORDS: catalysis, ceria, electrospinning, lithium cobalt oxide, metal oxide, nanoparticles ■ INTRODUCTIONBecause of their large ratio of surface area to volume and interconnected porosity, metal oxide meshes have been proposed for applications in catalysis, energy storage, and sensors.1−3 Various bottom-up approachessuch as vapor− liquid−solid (VLS) 4 and vapor−solid (VS) 5 growthand topdown techniquessuch as nanocarving 6 and electrospinning 7 have been described. Among these techniques, electrospinning is probably the most versatile, because it allows the fabrication of fibrous mats from a wide variety of both organic and/or inorganic materials. 8,9 Moreover, it allows for control over the diameter, morphology, porosity, alignment, and composition of the resulting fibers. 10,11Calcination of electrospun mats obtained from metal oxide precursors is a commonly used approach because of its facility and potential for upscaling. The calcination process is usually applied to mixtures of polymers/metal oxide precursors and it is based on an oxidative conversion of the polymeric component by heat treatment. There are many successful examples in literature for the fabrication of inorganic fibers by calcination of precursor materials prepared by sol−gel, 12−18 polymer-based sol−gel processes, 19−22 or from electrospinning of polymer dispersions in the presence of ex situ formed colloids.23−27 Upon increase of the temperature, metal oxide crystals nucleate and grow while the polymeric component undergoes degradation. 28,29 In the electrospinning of inorganic precursor, one has to take into account that the calcination leads almost automatically to a shrinkage of the fibers because the polymer template is removed. After calcination, the nanofibers are usually more brittle 30 because of their thinner section and the internal stress generated by the shrinkage. Therefore, an additional material that is not mechanically or chemically affected by the calcination process needs to be incorporated in the fibers during the electrospinning.The recently reviewed electrospinning of colloids 31 has been explored for the ...

show abstract

Section: ■ Introductionmentioning

confidence: 99%

Hierarchically Structured Metal Oxide/Silica Nanofibers by Colloid Electrospinning

Horzum

Muñoz‐Espí

Glaßer

et al. 2012

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…Research interests in metal oxide nanowires commenced in 1990s. Up to now, there have been a considerable number of reports on success in the synthesis of 1-dimensional nanocrystalline structured nanowires of various metal oxides, such as CuO (Wang, Zhan et al 2001;Jiang, Herricks et al 2002), MgO (Ma and Bando 2003), ZnO (Tian, Voigt et al 2003;Vayssieres 2003;Heo, Norton et al 2004;Wang, Song et al 2007;Manoharan, Desai et al 2008), TiO 2 (Lakshmi, Partissi et al 1997;Li and Wang 1999;Li and Xia 2003;Wu, Shih et al 2005;Wu, Shih et al 2006), Al 2 O 3 (Valcarcel, Souto et al 1998;Xiao, Han et al 2002), Ga 2 O 3 (Wu, Song et al 2000), In 2 O 3 (Li, Zhang et al 2003), SnO 2 (Dai, Pan et al 2001), Sb 2 O 5 (Guo, Wu et al 2000), V 2 O 5 (Chen, Sun et al 2002), BaTiO 3 (Urban, Spanier et al 2003), etc. The methodology of synthesis is now well developed.…”

Section: Introductionmentioning

confidence: 99%

“…The methodology of synthesis is now well developed. Reported techniques include vapor-solid phase technique (Valcarcel, Souto et al 1998;Wu, Song et al 2000;Jiang, Herricks et al 2002;Ma and Bando 2003;Wu, Shih et al 2005;Wu, Shih et al 2006), chemical solution deposition (sol-gel) (Lakshmi, Partissi et al 1997;Urban, Spanier et al 2003), template etching (Xiao, Han et al 2002), percipitation (Tian, Voigt et al 2003;Vayssieres 2003), micro-emulsion (Guo, Wu et al 2000), flux growth (Dai, Pan et al 2001) and others. These are well reviewed by Shangkar et al (Shankar and Raychaudhuri 2005).…”

Section: Introductionmentioning

confidence: 99%

Metal Oxide Nanowires – Structural and Mechanical Properties

Lian¹,

Sow²,

Lim³

et al. 2011

Nanowires - Fundamental Research

View full text Add to dashboard Cite

“…13 ANWs have recently been prepared by vapor-liquid-solid growth, 14 hydrothermal synthesis, 15 16 arc-plasma, 17 and high-temperature oxidization; 18 however, other methods, such as chemical etching porous alumina membranes (PAMs) in NaOH solutions to get ANWs or ANTs, were also reported by Han and Xu. 19 20 In this work, we report a convenient and inexpensive way to produce a high yield of ANWs and ANTs by etching PAMs in phosphoric acid solution * Author to whom correspondence should be addressed.…”

Section: Introductionmentioning

confidence: 99%

A Facile Approach to Synthesize Alumina Nanostructures at Room Temperature

Li¹,

Ma²,

Cao³

2010

j nanosci nanotechnol

View full text Add to dashboard Cite

Alumina nanostructures, nanowires, and semicolumn nanotubes with high aspect ratios were synthesized by the chemical etching of porous alumina membranes (PAMs) in phosphoric acid solution. The morphology and structure of alumina nanostructures were analyzed by scanning electron microscopy (SEM), energy dispersive spectrum (EDS), and X-ray diffraction (XRD), respectively. The results showed that the typical features of highly flexible nanostructures were around 20-40 nm in diameter and around 100 m in length. EDS analysis indicated that the nanostructures were constructed by aluminum oxide. The crystalline structure of the alumina nanostructures was amorphous, which was in accordance with that of the PAMs. Furthermore, the morphology of the PAMs was characterized in detail by atomic force microscope (AFM) and SEM. On the basis of AFM and SEM observations, a possible formation mechanism of alumina nanostructures was discussed, and the inhomogeneous dissolution between the triple points and the side walls was considered to be the essential factor deciding the formation of nanostructures.

show abstract

Development of Single-Crystal α-Al2O3 Fibers by Vapor-Liquid-Solid Deposition (VLS) from Aluminum and Powdered Silica

Cited by 103 publications

References 1 publication

Hierarchically Structured Metal Oxide/Silica Nanofibers by Colloid Electrospinning

Hierarchically Structured Metal Oxide/Silica Nanofibers by Colloid Electrospinning

Metal Oxide Nanowires – Structural and Mechanical Properties

A Facile Approach to Synthesize Alumina Nanostructures at Room Temperature

Contact Info

Product

Resources

About