Graphene oxide-Li⁺@C₆₀ donor-acceptor composites for photoenergy conversion

An ionic endohedral metallofullerene (Li⁺@C₆₀) with mild hydrophilic nature was combined with graphene oxide (GO) to construct a donor-acceptor composite in neat water. The resulting composite was characterised by UV-Vis and Raman spectroscopy, powder X-ray diffraction, dynamic light scattering measurements and transmission electron microscopy. Theoretical calculations (DFT at the B3LYP/6-31(d) level) were also utilized to gain further insight into the composite formation. As detected by electron paramagnetic resonance spectroscopy, photoexcitation of the GO-Li⁺@C₆₀ composite results in electron transfer from GO to the triplet excited state of Li⁺@C₆₀, leading to photocurrent generation at the OTE/SnO₂ electrode.