Figure 6

XPS spectra for APTMS-treated silica nanoparticles: (a) APTMS-1, (b) APTMS-2, and (c) APTMS-3 (yellow: -NH3+, blue: -NH2).

XPS spectra for APTMS-treated silica nanoparticles: (a) APTMS-1, (b) APTMS-2, and (c) APTMS-3 (yellow: -NH3+, blue: -NH2).