To derive the mechanism of HP-NCs decomposition, let's consider the radical formation upon illumination, as shown by EPR measurements. In HPs, photogenerated electrons in the conduction band (CB) can be absorbed by oxygen, leading to the formation of •O2 free radicals. Similarly, photogenerated holes in the valence band (VB) can convert OH-ions to •OH radicals. Therefore, we can infer the decomposition mechanism is based on photoinduced radical production in HPs, as described in Table .