Electrochemical growth of ZnO nanowires on atomic layer deposition coated polystyrene sphere templates

We report on the electrochemical growth of n-type ZnO NWs on thin films of atomic layer deposited ZnO on polystyrene spheres. The development of crystal agglomerates during ALD is shown to control the diameter of nanowires obtained by electrochemical deposition. Increasing the thickness of the ALD coating from 20 nm to 100 nm increases the crystallite size from about 10 nm to 22 nm on the polystyrene spheres as well as the maximum agglomerate size from 80 nm to 190 nm of the coatings. Subsequent electrochemical deposition with identical parameters showed that the resulting ZnO nanowire diameter is almost 1:1 related to the agglomerate dimensions of the ALD coating. This effect offers another degree of freedom in synthesizing transparent, high surface, tailored urchin-inspired building blocks having applications in solar cells and low wetting coatings.