Modulation of bandgap and electrical conductivity in europium doped single ZnO nanorod device

We investigate the effect of europium doping on the optical properties and electrical conductivity of hydrothermally grown ZnO nanorods. The widening of optical bandgap with europium doping occurs because of the Burstein-Moss effect upto 0.8% and bandgap renormalization is observed at higher concentration. The temperature-dependent resistivity measurements of the individual nanorods reveal that the intrinsic electrical conductivity is a combination of thermally activated and nearest-neighbor hopping conduction processes at high and low-temperature regimes, respectively. We can successfully correlate that the modulation of carrier concentration in the defect D and D− bands can tune both bandgap and electron transport in Eu doped ZnO nanorods.