Fig. 7

Cathodoluminescence data from a single ZnO NR transferred to a Si substrate. a A spectrum from the entire NR. b An SEM image of the investigated NR was recorded simultaneously with the luminescence data. The growth direction is along the arrow. c Hyperspectral luminescence map recorded along the line in b. The x-axis is the wavelength, the y-axis in the spatial position and the intensity is plotted in false color scale, as indicated in the figure. Note that the intensity of the defect band around 620 nm is enhanced by a factor of 4