Figure 1.

SEM images of colloidal carbon spheres produced by the one-step approach by heating at 180 °C for 4 h under various concentrations:a1.5 M,b1.0 M,c0.6 M,d0.4 M,e0.2 M, andf0.1 M

Chen et al. Nanoscale Research Letters 2009 4:971-976   doi:10.1007/s11671-009-9343-5