A novel approach to fabricate an ordered array of ZnO nanoflowers, consisting of uniform polymer cores
of 100s of nanometer diameter decorated with ZnO nanorods of 10s of nanometer diameter, is presented.
The 2-stage method combines the formation of ZnO seed layer by pulsed laser deposition (PLD) onto a
colloidally assembled polystyrene sphere monolayer and the subsequent hydrothermal growth of ZnO
nanowires (NWs). The main advantages of this methodology are low cost and the large area scalability
of perfectly ordered hierarchical structures. More importantly, the process enables a versatile control
of dimensions and morphologies of ZnO NWs as well as control of the core diameter by changing the
polystyrene sphere diameter. A strong improvement of light scattering by such arrays is observed, offering
promise as building blocks in different types of solar cells and potentially useful for a wide variety of
applications in optoelectronic devices.