Table 4.

CuO-np and CuO-np-C₁₈ compared to the other materials for Congo Red photochemical removal.

Type of nanoparticles	Source of irradiation	Photochemical removal, %	Reference
ZnO	Sun light	85	[46]
CuO nano sheets	UV lamp	12	[14]
BiGdWO6	Sun light	90	[47]
TiO2	Hg lamp	100	[48]
Nanocomposite films	High pressure Hg lamp	85	[49]
CuO-np	Sun light	90	This work
CuO-np-C18	Sun light	95	This work