Metal catalyst-assisted growth of GaN nanowires on graphene films for flexible photocatalyst applications

• Published in: Current applied physics Vol. 14; no. 11; pp. 1437 - 1442
• Main Authors: Park, Jun Beom, Kim, Nam-Jung, Kim, Yong-Jin, Lee, Sang-Hyup, Yi, Gyu-Chul
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2014; 한국물리학회
• Subjects: Catalysts; Foils; Gallium nitrides; GaN; Graphene; Nanostructure; Nanowire; Nanowires; Nickel; Photocatalysis; Photocatalyst; 물리학; Nanowire; GaN; Graphene; Photocatalyst
• ISSN: 1567-1739; 1878-1675
• DOI: 10.1016/j.cap.2014.08.007

We report the growth of high-areal-density GaN nanowires on large-size graphene films using a nickel (Ni) catalyst-assisted vapor-liquid-solid (VLS) method. Before the nanowire growth, the graphene films were prepared on copper foils using hot-wall chemical vapor deposition and transferred onto SiO2/Si substrates. Then, for catalyst-assisted VLS growth, Ni catalyst layers with thickness of a few nanometers were deposited on the graphene-coated substrates using a thermal evaporator. We investigated the effect of the Ni catalyst thickness on the formation of GaN nanowires. Furthermore, the structural and optical characteristics of GaN nanowires were investigated using X-ray diffraction, transmission electron microscopy, and photoluminescence spectroscopy. The GaN nanowires grown on graphene films were transferred onto polymer substrates using a simple lift-off method for applications as flexible photocatalysts. Photocatalysis activities of the GaN nanowires prepared on the flexible polymer substrates were investigated under bending conditions.