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Palladium-Decorated Hydrogen-Gas Sensors Using Periodically Aligned Graphene Nanoribbons
journal contribution
posted on 2014-08-13, 00:00 authored by Yusin Pak, Sang-Mook Kim, Huisu Jeong, Chang Goo Kang, Jung Su Park, Hui Song, Ryeri Lee, NoSoung Myoung, Byoung Hun Lee, Sunae Seo, Jin Tae Kim, Gun-Young JungPolymer residue-free graphene nanoribbons (GNRs) of 200 nm
width at 1 μm pitch were periodically generated in an area of
1 cm2 via laser interference lithography using a chromium
interlayer prior to photoresist coating. High-quality GNRs were evidenced
by atomic force microscopy, micro-Raman spectroscopy, and X-ray photoelectron
spectroscopy measurements. Palladium nanoparticles were then deposited
on the GNRs as catalysts for sensing hydrogen gases, and the GNR array
was utilized as an electrically conductive path with less electrical
noise. The palladium-decorated GNR array exhibited a rectangular sensing
curve with unprecedented rapid response and recovery properties: 90%
response within 60 s at 1000 ppm and 80% recovery within 90 s in nitrogen
ambient. In addition, reliable and repeatable sensing behaviors were
revealed when the array was exposed to various gas concentrations
even at 30 ppm.