TEM images and size distribution diagrams of GNPs. They were synthesized at boiling state under addition of different NaOH content of (A1) 3.1 mM, (A2) 4.4 mM, (A3) 5.3 mM, and (A4) 6.6 mM, respectively. Scale bar: 50 nm.
Li et al. Nanoscale Research Letters 2011 6:440 doi:10.1186/1556-276X-6-440