Improved performance of dye-sensitized solar cells using dual-function TiO2 nanowire photoelectrode.

Optics express

PubMedID: 26406757

Akbar ZA, Oh JH, Hadmojo WT, Yang SJ, Do YR, Jang SY. Improved performance of dye-sensitized solar cells using dual-function TiO2 nanowire photoelectrode. Opt Express. 2015;23(19):A1280-7.
A unique, hierarchically structured, aggregated TiO2 nanowire (A-TiO2-nw) is prepared by solvothermal synthesis and used as a dual-functioning photoelectrode in dye-sensitized solar cells (DSSCs). The A-TiO2-nw shows improved light scattering compared to conventional TiO2 nanoparticles (TiO2-np) and dramatically enhanced dye adsorption compared to conventional scattering particles (CSP). The A-TiO2-nw is used as a scattering layer for bilayer photoelectrodes (TiO2-np/A-TiO2-nw) in DSSCs to compare the cell performance to that of devices using state-of-the-art photoelectrode architectures (TiO2-np/CSP). The DSSCs fabricated using bilayers of TiO2-np/A-TiO2-nw show improved power conversion efficiency (9. 1%) and current density (14. 88 mA cm-2) compared to those using single-layer TiO2-np (7. 6% and 11. 84 mA cm-2) or TiO2-np/CSP bilayer structures (8. 7% and 13. 81 mA cm-2). The unique contribution of the A-TiO2-nw layers to the device performance is confirmed by studying the incident photon-to-current efficiency. The enhanced external quantum efficiencies at approximately 520 nm and 650 nm clearly reveal the dual functionality of A-TiO2-nw. These unique properties of A-TiO2-nw may be applied in other devices utilizing light-scattering n-type semiconductor.