Figure 1.

(a) Schematic representation of a photocatalytic reaction mediated by a semiconductor nanocrystal. Photoexcited electrons migrate to the surface and reduce an electron acceptor (A), while the holes oxidize an electron donor (D). This process is in competition with electron–hole recombination pathways. (b) Energy level diagram for a photocatalytic reaction, indicating energetic requirements for valence and conduction band edges (E_VB and E_CB) with respect to reduction potentials of the donor and acceptor (E(D⁺/D) and E(A/A⁻)).