Effects of electron donors on the performance of plasmon-induced photovoltaic cell

In this paper, charge separation of Au-TiO₂ nanocomposites under visible light irradiation is investigated by transient absorption spectroscopy (TAS), as well as steady-state absorbance studies. The effects of electron donors on the performance of plasmon-induced photovoltaic cell are studied by employing three kinds of donors: [Fe(CN)₆]^4-, Fe²⁺, and ferrocenecarboxylic acid, since the apparent formal potential of [Fe(CN ₆]⁴- and ferrocenecarboxylic acid is more negative and more positive than that of Fe²⁺, respectively, providing the opportunity to determine the influence of donors on the open-circuit photovoltage and short-circuit photocurrent. The experimental results indicate that both the open-circuit photovoltage and the short-circuit photocurrent are not simply dependent on the apparent formal potential of the donors. In addition, transient absorbance measurements show that the regeneration rates of the oxidized gold nanoparticles decreases in the order: Fe²⁺ > ferrocenecarboxylic acid > [Fe(CN)₆]^4-.