Strategic design of Cu/TiO2-based photoanode and rGO-Fe3O4-based counter electrode for optimized plasmonic dye-sensitized solar cells

The current research work demonstrates the modification of both functional electrodes of a plasmonic dye-sensitized solar cell (PDSSC) to fabricate a low-cost and efficient solar device. The copper-doped titania (Cu/TiO2) nanocomposite and hybrid magnetite nanoparticles decorated reduce graphene oxide (rGO/Fe3O4) nanocomposite were produced by a facile single step wet synthesis approach by utilizing non-toxic and cost-efficacious precursors. The as-synthesized nanocomposites were comprehensively analyzed by using scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, thermogravimetric analysis and UV–Vis spectroscopic techniques to evidently confirm the formation of Cu/TiO2 and hybrid rGO/Fe3O4 nanocomposites successfully. The photovoltaic parameters of the PDSSCs were investigated by measuring J-V characteristics and IPCE spectra. The Cu/TiO2 nanocomposite based photoanode demonstrated power conversion efficiency (PCE) of 3.89% with platinum (Pt) and 2.20% with hybrid rGO/Fe3O4 counter electrodes (CEs) respectively in PDSSCs. The hybrid rGO/Fe3O4 CE based PDSSC approached to 57% of the efficiency of the traditional platinum electrode with Cu/TiO2 and 70% with that of pristine TiO2 based photoanodes. The reasonable enhancement in efficiency might be ascribed to uniform dispersion of catalytic Fe3O4 nanoparticles on the surface of rGO nanosheets and due to plasmonic effect of Cu nanoparticles. The results suggested that the synergistic combination of modified functional electrodes in plasmonic DSSCs exhibited a reasonable efficiency and thus could prove to be as an effective substituent of traditional and expensive Pt.