[Retracted] Heavy Metal Removal from Aqueous Effluents by TiO₂ and ZnO Nanomaterials

Table 2

Removal performance of ZnO for common heavy metals pollutants [5, 46].

Ion	Removal performance		Removal mechanism
	Visible light	UV light
Ag (I)	Inadequate	Acceptable	Adsorption and redox
Cr (VI)	Medium	Inadequate	Adsorption and redox
Pb (II)	Medium	Acceptable	Adsorption and redox
Mn (II)	Inadequate	Inadequate	Adsorption
Cu (II)	Acceptable	Acceptable	Adsorption
Cd (II)	Inadequate	Inadequate	Adsorption
Ni (II)	Inadequate	Inadequate	Adsorption