Impact of Anionic Dopant Precursor on Nanostructured ZnO thin Films Surface Morphologies

The aim of this study is to investigate the impact of an anionic precursor [N2 gas and triethyleneamine (TEA) as nitrogen dopant source] to prepare anionic doped ZnO thin films surface morphologies, via a novel route - hydrothermal solution deposition at low temperature. The effect of dopant concentration under both with and without pH control was studied. The less populated doped ZnO crystal nearly had the same band gap as compared to undoped ZnO thin films. The photocatalytic activity of selected doped ZnO thin films were studied for the degrdation of 10 mg L-1 Methylene Blue under UV irradiation of 254nm. Based on the 1st order reaction rate constant results the morphology N2:S2-MS has shown highest degradation followed by N:S1-MS. Overall, the photocatalytic activity order is N2:S2-MS andgt; N:S1-MS andgt; N:S2-CG andgt; N:S1-CG. In general, a significant variation in surface morphologies, crystal size and population, porosity and orientation were observed. This tailored-made variation enabled the doped ZnO thin films to successfully degrade the waste methylene blue effluents.