Table 1.

ZnO synthesis and resultant morphology

Techniques	ZnO morphology	References
Microwave decomposition	Sphere	Jalal et al. [9]
Simple wet chemical route	Nano and micro-flowers, dumbbell shaped, rice flakes, and rings	Ramani et al. [129]
Deposition process	Dumbbell- and rod-shaped ZnO
Simple precipitation method	Nano-flakes	Kumar et al. [146]
Hydrothermal synthesis	Hexagonal prismatic rods	Stanković et al. [36]
Solvothermal method	Nano-flowers, nanorods, nano-spheres	Talebian et al. [77]
Microwave hydrothermal method	Mulberry-like	Ma et al. [78]
Hydrothermal technique	Nanorods	Hafez et al. [147]