title: A simple low temperature synthesis route for ZnO-MgO core-shell nanowires.
abstract: We report a hydrothermal synthesis method for MgO shell coatings directly onto the surface of ZnO nanowire arrays. The entire process can be carried out below 100 °C. The MgO shells are produced by the addition of 10 mM magnesium nitrate with 0.2 M sodium hydroxide in water, resulting in a shell thickness of up to 8 nm, verified by high resolution transmission electron microscopy. The viability of the MgO layer as a functional element of optoelectronic devices was tested on solid-state organic hole-transporter based dye-sensitized solar cells. Incorporation of the MgO shell into the solar cell resulted in substantive efficiency improvements of over 400% in comparison to the pristine ZnO nanowire based photovoltaics, indicating that electrons can efficiently tunnel through the 'insulating' MgO shell.
authors.affiliation: Nanoscience Centre, Department of Engineering, The University of Cambridge, 11 J J Thomson Avenue, Cambridge CB3 0FF, UK.
authors.forename: N O V
authors.initials: NO
authors.lastname: Plank
authors.forename: H J
authors.initials: HJ
authors.lastname: Snaith
authors.forename: C
authors.initials: C
authors.lastname: Ducati
authors.forename: J S
authors.initials: JS
authors.lastname: Bendall
authors.forename: L
authors.initials: L
authors.lastname: Schmidt-Mende
authors.forename: M E
authors.initials: ME
authors.lastname: Welland