The controlled modification of the electronic properties of ZnO nanorods via transition metal doping is reported. A series of ZnO nanorods were synthesized by chemical bath growth with varying Co content from 0 to 20 atomic % in the growth solution. Optoelectronic behavior was probed using cathodoluminescence, time-resolved luminescence, transient absorbance spectroscopy, and the incident photon-to-current conversion efficiency (IPCE). Analysis indicates the crucial role of surface defects in determining the electronic behavior. Significantly, Co-doping extends the light absorption of the nanorods into the visible region, increases the surface defects, shortens the non-radiative lifetimes, while leaving the radiative lifetime constant. Furthermore, for 1 atomic % Co-doping the IPCE of the ZnO nanorods is enhanced. These results demonstrate that doping can controllably tune the functional electronic properties of ZnO nanorods for applications.
@article{arxiv.2006.16740,
title = {Optical properties and carrier dynamics in Co-doped ZnO nanorods},
author = {Aswathi K. Sivan and Alejandro Galan-Gonzalez and Lorenzo Di Mario and Nicolas Tappy and Javier Hernandez-Ferrer and Daniele Catone and Stefano Turchini and Ana M. Benito and Wolfgang K. Maser and Simon Escobar Steinvall and Anna Fontcuberta i Morral and Andrew Gallant and Dagou A. Zeze and Del Atkinson and Faustino Martelli1},
journal= {arXiv preprint arXiv:2006.16740},
year = {2020}
}