Comparison of synthesis techniques for zinc oxide nanoparticles: advantages and disadvantages.

Synthesis technique	Advantages	Disadvantages
Sol–gel method	(1) Precise control over nanoparticle size	(1) Requires high temperatures
	(2) Uniform particle size distribution	(2) May involve toxic chemicals
	(3) Versatile synthesis conditions	(3) Energy-intensive process
Hydrothermal synthesis	(1) Rapid synthesis	(1) High-pressure conditions
	(2) High purity of nanoparticles	(2) Limited control over particle shape
	(3) Scalable for industrial production	(3) Energy-intensive process
Green synthesis	(1) Environmentally friendly	(1) Relatively longer synthesis times
	(2) Cost-effective	(2) Variability in nanoparticle properties
	(3) Biocompatible	(3) Limited scalability for industrial use