Zinc oxide and zinc hydroxide formation via aqueous precipitation: Effect of the preparation route and lysozyme addition

Abstract

h i g h l i g h t s g r a p h i c a l a b s t r a c tAqueous precipitation products of Zn(NO 3 ) 2 and NaOH were prepared. Synthesis route and lysozyme addition affected morphology of the products. Aqueous precipitation products of Zn(NO 3 ) 2 and NaOH obtained by changing the method of combining the reactants and by using lysozyme as an additive were investigated. In the case of single addition method, octahedral ε-Zn(OH) 2 and plate-like b-Zn(OH) 2 structures formed in the absence and in the presence of lysozyme, respectively. Calcination of these Zn(OH) 2 samples at 700 C yielded porous ZnO structures by conserving the template crystals. When zinc source was added dropwise into NaOH solution, predominantly clover-like ZnO crystals were obtained independent of lysozyme addition. Mixed spherical and elongated ZnO morphology was observed when NaOH was added dropwise into Zn(NO 3 ) 2 solution containing lysozyme. Lysozyme contents of the precipitation products were estimated as in the range of~5e20% and FTIR indicated no significant conformational change of lysozyme in the composite. These results suggest that lysozyme-ZnO/Zn(OH) 2 composite materials may have a value as an antibacterial material.

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Carbon Nano‐Onion and Zinc Oxide Composites as an Electron Transport Layer in Inverted Organic Solar Cells

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The green synthesis of Ag/ZnO in montmorillonite with enhanced photocatalytic activity

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