Fabrication of large Pt nanoparticles-decorated rGO counter electrode for highly efficient DSSCs

An overview of the preparation and application of counter electrodes for DSSCs

Dye-sensitized solar cells (DSSCs) are potential products for the next generation of photovoltaic technology, which is one of the research hotspots in photovoltaics. The counter electrode in DSSCs collects electron in the external circuit and catalyzes the reduction of the redox electrolyte and hole transport in the solid electrolyte. Thus, it undoubtedly has an important impact on the photovoltaic performance, long-term stability, and cost of DSSCs. In this work, the materials of counter electrodes are classified into metals, carbon materials, conductive polymers, and inorganic compounds. The preparation, mechanism, conversion efficiency, and properties of counter electrodes are reviewed.

Enhanced Efficiency of Dye-Sensitized Solar Cells Based on Polymer-Assisted Dispersion of Platinum Nanoparticles/Carbon Nanotubes Nanohybrid Films as FTO-Free Counter Electrodes

In this study, polymer-assisted dispersants are used to stabilize the nanohybrids of platinum nanoparticles (PtNPs)/carbon nanotubes (CNTs) through non-covalent bond forces. These dispersants aim to replace the florine-doped tin oxide (FTO) glass in traditional dye-sensitized solar cells (DSSCs) as counter electrodes. The large specific surface area, high conductivity, and redox potential of PtNPs/CNT nanohybrids are used as the basis to utilize them as the counter electrode material to fabricate a dye-sensitized solar cell. The conductivity results indicate that the resistance of the PtNP/CNT nanohybrid film can be reduced to 7.25 Ω/sq. When carbon nanotubes are mixed with platinum nanoparticles at a weight ratio of 5/1, the photoelectric conversion efficiency of DSSCs can reach 6.28%. When using the FTO-containing substrate as the counter electrode, its conversion efficiency indicates that the micro-/nano-hybrid material formed by PtNPs/CNTs also exhibits an excellent photoelectric conversion efficiency (8.45%) on the traditional FTO substrate. Further, a large-area dye-sensitive cell is fabricated, showing that an 8 cm × 8 cm cell has a conversion efficiency of 7.95%. Therefore, the traditional Pt counter electrode can be replaced with a PtNP/CNT nanohybrid film, which both provides dye-sensitive cells with a high photoelectric conversion efficiency and reduces costs.