Direct synthesis of beta gallium oxide nanowires, nanobelts, nanosheets and nanograsses by microwave plasma

ABSTRACTWe have synthesized highly crystalline β-gallium oxide tubes, nanowires, and unique one-dimensional structures in the form of nanopaintbrushes using molten gallium and microwave plasma containing a mixture of monoatomic oxygen and hydrogen. Multiple nucleation and growth of gallium oxide nanostructures occurred directly out of molten gallium upon exposure to an appropriate composition of hydrogen and oxygen in the gas phase. Gallium oxide nanowires were 20 to 100 nm thick and tens to hundreds of microns long. In addition to these morphologies, we also report for the first time, non-template based synthesis of novel 2-D networks of crystalline gallium oxide nanowires and nanotubes. Demonstration of this technique with gallium oxide certainly presents a new route for synthesis of nanostructures of other important metal oxides such as indium oxide, tin oxide, and zinc oxide.

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Controlled Fabrication of Quality ZnO NWs/CNTs and ZnO NWs/Gr Heterostructures via Direct Two-Step CVD Method

Nanomaterials ◽

10.3390/nano11071836 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1836

Author(s):

Nicholas Schaper ◽

Dheyaa Alameri ◽

Yoosuk Kim ◽

Brian Thomas ◽

Keith McCormack ◽

...

Keyword(s):

Direct Synthesis ◽

Chemical Vapor ◽

Single Walled Carbon Nanotubes ◽

Materials Synthesis ◽

Oxide Nanowires ◽

Cvd Method ◽

Thermal Actuators ◽

Potential Applications ◽

Walled Carbon Nanotubes ◽

Scalable Production

A novel and advanced approach of growing zinc oxide nanowires (ZnO NWs) directly on single-walled carbon nanotubes (SWCNTs) and graphene (Gr) surfaces has been demonstrated through the successful formation of 1D–1D and 1D–2D heterostructure interfaces. The direct two-step chemical vapor deposition (CVD) method was utilized to ensure high-quality materials’ synthesis and scalable production of different architectures. Iron-based universal compound molecular ink was used as a catalyst in both processes (a) to form a monolayer of horizontally defined networks of SWCNTs interfaced with vertically oriented ZnO NWs and (b) to grow densely packed ZnO NWs directly on a graphene surface. We show here that our universal compound molecular ink is efficient and selective in the direct synthesis of ZnO NWs/CNTs and ZnO NWs/Gr heterostructures. Heterostructures were also selectively patterned through different fabrication techniques and grown in predefined locations, demonstrating an ability to control materials’ placement and morphology. Several characterization tools were employed to interrogate the prepared heterostructures. ZnO NWs were shown to grow uniformly over the network of SWCNTs, and much denser packed vertically oriented ZnO NWs were produced on graphene thin films. Such heterostructures can be used widely in many potential applications, such as photocatalysts, supercapacitors, solar cells, piezoelectric or thermal actuators, as well as chemical or biological sensors.

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Unconventional Gallium Oxide Nanowires

Small ◽

10.1002/smll.200500022 ◽

2005 ◽

Vol 1 (8-9) ◽

pp. 883-888 ◽

Cited By ~ 41

Author(s):

Jinhua Zhan ◽

Yoshio Bando ◽

Junqing Hu ◽

Fangfang Xu ◽

Dmitri Golberg

Keyword(s):

Gallium Oxide ◽

Oxide Nanowires

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Gas Phase Production of Metal Oxide Nanowires Using a Microwave Plasma Reactor

ECS Meeting Abstracts ◽

10.1149/ma2008-01/21/771 ◽

2008 ◽

Keyword(s):

Metal Oxide ◽

Gas Phase ◽

Microwave Plasma ◽

Plasma Reactor ◽

Oxide Nanowires ◽

Metal Oxide Nanowires ◽

Phase Production

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Nanoweb Formation: 2D Self-Assembly of Semiconductor Gallium Oxide Nanowires/Nanotubes

Advanced Functional Materials ◽

10.1002/adfm.200304391 ◽

2003 ◽

Vol 13 (7) ◽

pp. 576-581 ◽

Cited By ~ 25

Author(s):

U.M. Graham ◽

S. Sharma ◽

M.K. Sunkara ◽

B.H. Davis

Keyword(s):

Self Assembly ◽

Gallium Oxide ◽

Oxide Nanowires

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Extremely non-equilibrium oxygen plasma for direct synthesis of metal oxide nanowires on metallic substrates

Journal of Physics D Applied Physics ◽

10.1088/0022-3727/44/17/174028 ◽

2011 ◽

Vol 44 (17) ◽

pp. 174028 ◽

Cited By ~ 18

Author(s):

Miran Mozetic

Keyword(s):

Metal Oxide ◽

Oxygen Plasma ◽

Direct Synthesis ◽

Oxide Nanowires ◽

Metallic Substrates ◽

Metal Oxide Nanowires ◽

Equilibrium Oxygen ◽

Non Equilibrium

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Synthesis and Cathodoluminescence of β-Ga2O3 Nanowires with Holes

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.18184 ◽

2008 ◽

Vol 8 (3) ◽

pp. 1284-1287

Author(s):

Xitian Zhang ◽

Zhuang Liu ◽

Suikong Hark

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Vapor Deposition ◽

Gallium Oxide ◽

Chemical Vapor ◽

Oxide Nanowires ◽

X Ray ◽

Transmission Electron ◽

Reactive Surfaces ◽

Scanning Electron

Gallium oxide nanowires were synthesized on Si (001) substrate by chemical vapor deposition, using a Ga/Ga2O3 mixture as a precursor and Au as a catalyst. The structure of the as-synthesized products was examined by X-ray powder diffraction and high-resolution transmission electron microscopy, and found to be monoclinic β-Ga2O3. The morphologies of the β-Ga2O3 nanowires were characterized by scanning electron microscopy. The majority of the nanowires contain holes along their length, but a few were also found without holes. The holes are believed to be formed by the reaction of adsorbed Ga droplets on reactive terminating surfaces of the nanowires. For nanowires where these reactive surfaces are not exposed, the reaction of Ga is retarded. Cathodoluminescence (CL) of the nanowires was measured. Three emission bands centered at 376, 454, and 666 nm, respectively, were observed.

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