Enhanced photocurrent production by bio-dyes of photosynthetic macromolecules on designed TiO2 film

The macromolecular pigment-protein complex has the merit of high efficiency for light-energy capture and transfer after long-term photosynthetic evolution. Here bio-dyes of A. platensis photosystem I (PSI) and spinach light-harvesting complex II (LHCII) are spontaneously sensitized on three types of designed TiO 2 films, to assess the effects of pigment-protein complex on the performance of bio-dye sensitized solar cells (SSC). Adsorption models of bio-dyes are proposed based on the 3D structures of PSI and LHCII and the size of particles and inner pores in the TiO 2 film. PSI shows its merit of high efficiency for captured energy transfer, charge separation and transfer in the electron transfer chain (ETC) and electron injection from F B to the TiO 2 conducting band. After optimization, the best short current (J SC ) and photoelectric conversion efficiency (η) of PSI-SSC and LHCII-SSC are 1.31 mA cm -2 and 0.47% and 1.51 mA cm -2 and 0.52%, respectively. The potential for further improvement of this PSI based SSC is significant and could lead to better utilization of solar energy.