Speaker
Level for award<br> (Hons, MSc, <br> PhD, N/A)?
PhD
Apply to be<br> considered for a student <br> award (Yes / No)?
Yes
Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?
Yes
Please indicate whether<br>this abstract may be<br>published online<br>(Yes / No)
Yes
Main supervisor (name and email)<br>and his / her institution
Francis B Dejene
Abstract content <br> (Max 300 words)<br><a href="http://events.saip.org.za/getFile.py/access?resId=0&materialId=0&confId=34" target="_blank">Formatting &<br>Special chars</a>
Key words: Semiconductor, Gallium, ZnO, DSSCs
Ga-doped ZnO (ZnO:Ga) nanoparticles were synthesized by precipitation reflux method. The effects of varying [Ga]/[Zn] doping ratios on the morphology, luminescence and optical properties of ZnO:Ga were investigated. Ga-doped ZnO transparent conducting materials have gained much interest in recent years due to their low resistivity, high transmittance, nontoxicity and resource availability [1]. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were performed for the nanoparticles. It was found that SEM images increased in size by increasing the [Ga]/[Zn] ratio up to 2 mol.% then reduced in size at higher doping ratios (3-5 mol.%). The diffraction patterns showed hexagonal wurtzite structure of ZnO. The crystallinity and crystallite sizes increased by increasing doping ratios to 2 mol. %, but decreased as doping ratios increased to 5%. The total reflectance spectra of ZnO:Ga samples are similar and show reflectance of 9–14% in the spectral region of 350 –700 nm. The % transmittance of ZnO:Ga in the UV region, was observed to increase with doping levels then reduce at higher % doping. Similarly, the highest excitonic peak emissions were seen at 2% [Ga]/[Zn] ratio from the PL spectra.
Reference: [1] M. Netrvalova, I. Novotny, L. Prusakova, V. Tvarozek, and P. Sutta, “Influence of deposition regime on physical properties of gallium-doped zinc oxide films,” Vacuum, vol. 86, no. 6, pp. 707–710, 2012.
