Ex-situ doping of ZnO structures as potential random lasers

Zinc oxide (ZnO) nanorods were formed on a glass substrate using chemical bath deposition (CBD) method for three hours at 96 °C. Doping of aluminum (Al) was realised by dipping into aluminum nitrate solution. XRD spectra shows reduced (002) peak related to the crystallinity of the synthesized ZnO with increasing doping concentrations. Doping with 35 mM exhibited highest Al concentration of 11.78 %. An apparent shift in bandgap energy with increasing doping concentration provides further evidence of doping occurring in the sample. Random lasing was observed at a pumping threshold of 9.0 mW and spectral width of 1.09 nm. Overall results indicate promising potential for random lasing to occur in ZnO nanorods doped under ex-situ doping conditions.