Summary: | Owing to its high electron mobility, zinc oxide represents a promising alternative to titanium dioxide as the working electrode material in dye-sensitized solar cells (DSCs). When zinc oxide is grown into 1-D nanowire arrays and incorporated into the working electrode of DSCs, enhanced electron dynamics and even a decoupling of electron transport (τ<sub>d</sub>) and electron lifetime (τ<sub>n</sub>) have been observed. In this work, DSCs with working electrodes composed of solution-grown, unarrayed ZnO nanorods are investigated. In order to determine whether such devices give rise to similar decoupling, intensity modulated photocurrent and photovoltage spectroscopies are used to measure τ<sub>d </sub>and τ<sub>n</sub>, while varying the illumination intensity. In addition, ZnO nanorod-based DSCs are compared with ZnO nanoparticle-based DSCs and nanomaterial shape is shown to affect electron dynamics. Nanorod-based DSCs exhibit shorter electron transport times, longer electron lifetimes, and a higher τ<sub>n</sub>/τ<sub>d</sub> ratio than nanoparticle-based DSCs.
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