This Account reviews our main achievements in the field of excited-state pr
operties of fullerene derivatives. The photosensitizing and electron-accept
or features of some relevant classes of functionalized fullerene materials
are highlighted, considering the impact of functionalization on fullerene c
haracteristics. In addition, the unique optimization in terms of redox pote
ntials, water-solubility, and singlet oxygen generation is presented for se
veral novel fullerene-based materials.