Figure 1.

a Schematic 3D illustration of n-ZnO NTs/p-GaN heterostructures LED device b I–V characteristics of the ZnO NTs–based light-emitting diode with threshold voltage ~5 V

Sadaf et al. Nanoscale Research Letters 2010 5:957-960   doi:10.1007/s11671-010-9588-z