Figure 2
From: Silica nanoparticle aggregation in calcite replacement reactions
Secondary electron images of amorphous silica sphere geometry and microstructures. (a) Polished surface of a twinned crystal with alternating sphere array orientation in an A-B-A-B pattern. Dashed lines highlight the {018} twin planes (TP). (b) HF acid-etched spheres show a concentric layering. Arrows highlight ~30 nm-sized subparticles. Scale bars: (a) 1 µm, (b) 100 nm.
