We have performed low energy cathodoluminescence spectroscopy (CLS) measurements on nanometer scale particles of SiO2. We investigated both hydrophobic and hydrophilic SiO2 specimens under ultrahigh vacuum (UHV) conditions in order to control surface chemical adsorption. CLS yielded evidence for energy levels deep in the band gap of these materials. Specifically, a set of spectral peaks appeared at similar to 1.2-1.3, 1.6-1.9, and similar to 2.7 eV in both hydrophobic and hydrophilic SiO2. The appearance of these features at energies well below the band edge of SiO2 (8.9 eV) is indicative of traps in the band gap which may play a role in the charge transfer process. We observed a strong intensity dependence of the features on incident electron beam energy with 1 (more surface) versus 2 keV (more bulk) excitation. This feature also displayed an increase with hydrophobicity, with particle size, as well as with additional surface chemical treatment. The 2.75-2.95 eV feature increase with larger hydrophobic particle size suggests that chemical conditions as well as surface area contribute to the peak intensity. Furthermore, particle size also affects peak energies as well, indicative of quantum size effects. In addition, they provide significant evidence for deep levels in wide band gap insulating SiO2 playing a role in triboelectric contact charging.