Fabrication of bimetallic inlaid working electrode for highly efficient dye sensitized solar cells

Abstract

Gold nanoparticles (AuNPs) including Au-Pink, Au-Orange, Au-Purple, Au-Blue were synthesized using chemical reduction method, their optical and morphological properties were characterized and they were used in PV devices. The active layer of dye-sensitized solar cells having titanium dioxide (TiO2) solid microsphere (MS) made up of nanoparticles granules were coated with AuNPs. This Au-TiO2 MS hybrid DSSC boosted light harvesting, charge separation, and improved the charge transportresulting in an improvement of both short circuit current and open circuit voltage. The power conversion was boosted 16% compared to the control photoanode of TiO2 solid microsphere. Further enhancement in the short circuit current was observed during the incorporation of both Au and Ag, bi-metallic nanoparticles in the TiO2 matrix. An overall photo to electron conversion efficiency of 8.73% was obtained due to the plasmonic cooperation effect of TiO2-Ag-Au hybrid structures, which is 65% increase over pure TiO2 DSSCs. The local electrified intensity enhancement around the individual Ag, Au nanoparticles and plasmonic coupling of the Ag-Au combination have been used to explain these results with finite-difference time-domain simulation.