Controllable Synthesis of Vapor-Liquid-Solid Grown GaN Nanowires for Photoelectrochemical Water Splitting Applications

High quality single crystalline GaN nanowires with large aspect ratio (>100) are synthesized on n-type Si (111) substrate via Au-catalyzed vapor-liquid-solid process. Morphology, crystal structure, and optical property of the as-synthesized GaN nanowires are characterized by means of X-ray diffraction, scanning/transmission electron microscopy, UV-vis diffuse reflection spectroscopy, and room temperature photoluminescence. The results indicate that the as-prepared GaN nanowires with a large aspect ratio are well crystallized in the hexagonal wurtzite structure, and a slight blue shift appears in both the absorption edge and emission peak probably due to the quantization effect. Photocatalytic H2evolution over the as-prepared GaN nanowires is performed with the incorporation of Pt or Rh as the cocatalyst, exhibiting greatly enhanced capability compared to the GaN powder tested under the same conditions. Moreover, photocatalytic CO2reduction over the GaN nanowires is also successfully realized using Pt or Rh as the cocatalyst, depending on which the products show a strong selectivity inherently related to the reductive electrons transferred by cocatalyst.

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Growth of GaN nanowires through a pyrolysis method with vapor–liquid–solid mechanism

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2006.07.131 ◽

2007 ◽

Vol 201 (9-11) ◽

pp. 5578-5581 ◽

Cited By ~ 3

Author(s):

Jie Zhan ◽

Rujun Liu ◽

Xiaopeng Hao ◽

Xutang Tao ◽

Minhua Jiang

Keyword(s):

Vapor Liquid Solid ◽

Gan Nanowires ◽

Pyrolysis Method ◽

Vapor Liquid Solid Mechanism ◽

Vapor Liquid

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Vapor-liquid-solid growth of GaN nanowires by reactive sputtering of GaAs

10.1063/1.4791229 ◽

2013 ◽

Author(s):

P. Mohanta ◽

P. Chaturvedi ◽

S. S. Major ◽

R. S. Srinivasa

Keyword(s):

Reactive Sputtering ◽

Vapor Liquid Solid ◽

Gan Nanowires ◽

Vapor Liquid Solid Growth ◽

Vapor Liquid

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Self-branching in GaN Nanowires Induced by a Novel Vapor-Liquid-Solid Mechanism

MRS Proceedings ◽

10.1557/proc-1058-jj04-03 ◽

2007 ◽

Vol 1058 ◽

Author(s):

Chang-Yong Nam ◽

Douglas Tham ◽

John E. Fischer

Keyword(s):

Chemical Vapor ◽

Building Blocks ◽

Direct Reaction ◽

Vapor Liquid Solid ◽

Practical Applications ◽

Gan Nanowires ◽

Vapor Liquid Solid Mechanism ◽

Vls Growth ◽

And Migration ◽

Vapor Liquid

ABSTRACTNanowires have great potential as building blocks for nanoscale electrical and optoelectronic devices. The difficulty in achieving functional and hierarchical nanowire structures poses an obstacle to realization of practical applications. While post-growth techniques such as fluidic alignment might be one solution, self-assembled structures during growth such as branches are promising for functional nanowire junction formation. In this study, we report vapor-liquid-solid (VLS) self-branching of GaN nanowires during AuPd-catalyzed chemical vapor deposition (CVD). This is distinct from branches grown by sequential catalyst seeding or vapor-solid (VS) mode. We present evidence for a VLS growth mechanism of GaN nanowires different from the well-established VLS growth of elemental wires. Here, Ga solubility in AuPd catalyst is limitless as suggested by a hypothetical pseudo-binary phase diagram, and the direct reaction between NH3 vapor and Ga in the liquid catalyst induce the nucleation and growth. The self-branching can be explained in the context of the proposed VLS scheme and migration of Ga-enriched AuPd liquid on Ga-stabilized polar surface of mother nanowires. This work is supported by DOE Grant No. DE-FG02-98ER45701.

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