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Quantum dot (QD) functionalized nanowire arrays are attractive structures for low cost high efficiency solar cells. QDs
have the potential for higher quantum efficiency, increased stability and lifetime compared to traditional dyes, as well as
the potential for multiple electron generation per photon. Nanowire array scaffolds constitute efficient, low resistance
electron transport pathways which minimize the hopping mechanism in the charge transport process of quantum dot
solar cells. However, the use of liquid electrolytes as a hole transport medium within such scaffold device structures
have led to significant degradation of the QDs. In this work, we first present the synthesis uniform single crystalline ZnO
nanowire arrays and their functionalization with InP/ZnS core-shell quantum dots. The structures are characterized using
electron microscopy, optical absorption, photoluminescence and Raman spectroscopy. Complementing
photoluminescence, transmission electron microanalysis is used to reveal the successful QD attachment process and the
atomistic interface between the ZnO and the QD. Energy dispersive spectroscopy reveals the co-localized presence of
indium, phosphorus, and sulphur, suggestive of the core-shell nature of the QDs. The functionalized nanowire arrays are
subsequently embedded in a poly-3(hexylthiophene) hole transport matrix with a high degree of polymer infiltration to
complete the device structure prior to measurement.
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