Electrical and Optical Properties of Well-Aligned Ho3+-Doped ZnO Nanorods as an Alternative Transparent Conducting Oxide

In this study, the impacts of doping concentration on the crystal structure, morphology, electrical, and optical properties of Ho3+-doped zinc oxide (ZnO) nanorod (NR) arrays were studied. Structural and morphological characterizations showed that the Ho3+-doped ZnO NRs were crystallized in the (002) direction, and that they had a homogeneous distribution on the substrate. The crystallite sizes of the samples were between 50 nm and 65 nm. SEM analysis showed that every sample was hexagonal in shape. For the 1 and 5 mol.% Ho3+-doped ZnO NRs, the values for electrical conductivity were found to be 1.41 x 10(-7) and 8.29 x 10(-6) (omega cm)(-1) at 25 degrees C and 1.70 x 10(-5) and 1.24 x 10(-3) (omega cm)(-1) at 300 degrees C, respectively. The optical transmittances were between 80 and 93% for all the samples in the region from 400 to 1000 nm. The optical band gap values were determined to be between 3.180 and 3.195 eV.

Automated summary

This study investigated the effects of doping concentration on the crystal structure, morphology, electrical, and optical properties of Ho3+-doped zinc oxide nanorod arrays. The Ho3+-doped ZnO nanorods exhibited crystallization in the (002) direction with homogeneous distribution on the substrate. Variations in Ho3+ doping concentration resulted in differences in electrical conductivity and optical transmittance of the samples.