The fabrication and characterization of dye-sensitized solar cells with a branched structure of ZnO nanowires

To maximize dye absorption and improve energy conversion efficiency, we adopted a branched structure for single crystalline ZnO nanowires in dye-sensitized solar cells (DSSCs). The high-density branched structures of these ZnO nanowires were incorporated by a two-step seeding with zinc acetate dihydrate seeds. The ZnO nanowire DSSCs exhibited an overall efficiency of ∼0.46%. This represented a 35% improvement compared to the ZnO nanowire DSSCs with pillar-shaped ZnO nanowires. Our current density-voltage (J-V) characterizations suggest that the current densities and power conversion efficiencies were improved by increasing the surface area with these branched structures of ZnO nanowires in DSSCs.