Synthesis Approaches of Zinc Oxide Nanoparticles: The Dilemma of Ecotoxicity

Table 1

Physical properties of ZnO nanoparticles.

Physical appearance	White, colorless, odorless solid
Crystalline structure	Wurtzite
Molecular Weight	81.38 g/mol
Electron effective mass	60
Melting Point	1,975°C
Density	5.47 g/cm^2
Isoelectric point	9.5–10
Space group	-P63mc
Standard molar entropy	43.9 J·K^−1mol^−1
Standard enthalpy of formation	−348.0 kJ/mol