Hydrogen Production by Photoreforming of Renewable Substrates

Figure 5

Electron transfer paths in dye-sensitized TiO₂. 1: dye (S) excitation; 2: electron injection from the excited dye to TiO₂ conduction band (CB); 3: electron entrapment into Pt particles; 4: H⁺ reduction and H₂ evolution over the metallic site; 5: regeneration of the oxidized dye by an electron donor (D); 6: electron recombination in the oxidized dye. Readapted from [1].