Evolution of ZnO Nanoflower-Like Structure Formation and Growth during Synthesis and Paste Preparation
ZnO nanoflowers were synthesized by co-precipitation method at low temperature (80°C) for dye-sensitized solar cell applications. ZnO nanostructures were grown at various pH values from Zinc nitrate tetrahydrate [Zn (NO3)2.4H2O], HMTA (Hexamethylenetetramine) and Potassium Hydroxide (KOH). The results indicate that by increasing pH from 6 to 12, the ZnO morphology evolves from aggregrated particles, prism-like and eventually flower-like structures. According the Scherrer equation the particle size of (100), (002), and (101) peaks tends to drop as the pH increased. HMTA is known as an effective reductant to produce hexagonal ZnO rods of various lengths and cross-sections. Low HMTA led to smaller petal and further addition caused the petal became wider. Annealing temperature should not be higher than 200°C.
Risa Suryana, Kuwat Triyana, Khairurrijal, Heru Susanto and Sutikno
M. Iqbal et al., "Evolution of ZnO Nanoflower-Like Structure Formation and Growth during Synthesis and Paste Preparation", Advanced Materials Research, Vol. 1123, pp. 219-222, 2015