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Title: Synthesis and optoelectronic properties of ultrathin Ga 2 O 3 nanowires
Gallium oxide (Ga 2 O 3 ) and its most stable modification, monoclinic β-Ga 2 O 3 , is emerging as a primary material for power electronic devices, gas sensors and optical devices due to a high breakdown voltage, large bandgap, and optical transparency combined with electrical conductivity. Growth of β-Ga 2 O 3 is challenging and most methods require very high temperatures. Nanowires of β-Ga 2 O 3 have been investigated extensively as they might be advantageous for devices such as nanowire field effect transistors, and gas sensors benefiting from a large surface to volume ratio, among others. Here, we report a synthesis approach using a sulfide precursor (Ga 2 S 3 ), which requires relatively low substrate temperatures and short growth times to produce high-quality single crystalline β-Ga 2 O 3 nanowires in high yields. Even though Au- or Ag-rich nanoparticles are invariably observed at the nanowire tips, they merely serve as nucleation seeds while the nanowire growth proceeds via supply and local oxidation of gallium at the substrate interface. Absorption and cathodoluminescence spectroscopy on individual nanowires confirms a wide bandgap of 4.63 eV and strong luminescence with a maximum ∼2.7 eV. Determining the growth process, morphology, composition more » and optoelectronic properties on the single nanowire level is key to further application of the β-Ga 2 O 3 nanowires in electronic devices. « less
Authors:
; ;
Award ID(s):
1904843
Publication Date:
NSF-PAR ID:
10231056
Journal Name:
Journal of Materials Chemistry C
Volume:
8
Issue:
33
Page Range or eLocation-ID:
11555 to 11562
ISSN:
2050-7526
Sponsoring Org:
National Science Foundation
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