Fig. 4. TEM images of cCVD Si reference nanoparticles (a and b), pH 7.4 treated after 200 min (c and d) and pH 8.0 treated after 200 min (e and f), with elemental analysis based on EELS data to visualize elemental distribution, Si (a, c and e), O (b, d and f). Regions are imaged to see the hollow and dense nanoparticles in one frame. At pH 8.0, hollow nanoparticles are the main configuration, and the TEM images showing both hollow and dense nanoparticles are not representative of the sample.
