Plasma-reduced Pd/GO samples prepared in different pH values. (a) pH = 4, (b) pH = 5, (c) pH = 6, (d) pH = 7, (e) pH = 10 and (f) a zoom-in image of (c) with a cross-section analysis which shows the height of graphene and peaks arising from Pd nanoparticles. The scale of images (a) to (e) are 4 μm × 4 μm, and image (f) is 400 nm × 400 nm.
Yu et al. Nanoscale Research Letters 2012 7:234 doi:10.1186/1556-276X-7-234