Microwave Assisted Method on the Morphology of Aluminium Doped ZnO Nanocrystals

Abstract:

This study investigated the effect of aluminium dopant on ZnO morphologies synthesized by microwave assisted method. The precursors used were Zn (NO₃)₂.6H₂O, NaOH and AlCl₃.6H₂O. The conditions for microwave heating were 160 and 640W, 10 min with 5s ON/15s OFF step. Microwave assisted heating generates heat to activate the formation of ZnO. Phase study was carried by X-ray diffraction which confirmed the formation of wurtzite structure of ZnO for all synthesized conditions. Microstructure was studied by a scanning electron microscope which revealed different crystal morphologies of ZnO at different amount of Al doping concentrations. ZnO rod was about 3-5 μm in length and 200 500 nm in cross section with hexagonal crystal plane. During microwave heating, nucleation of ZnO rods started at a point leading growth into larger flowers. In this work, it was suggested that Al acted as a nucleating agent and affected the c-axis orientation for ZnO crystal growth. Small needles/rod-like crystals were observed probably due to fast nucleation and a decrease of growth on (002) plane.

• Periodical: Key Engineering Materials (Volume 608)
• Pages: 153-158
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.608.153
• Online since: April 2014
• Authors: Pat Sooksaen*, Malin Rapp, Kanokporn Potharin
• Keywords: Absorption, Microwave, Morpholoy, Zinc Oxide (ZnO)

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