“…In waste with azo dyes, such as MO dye, complete degradation can result in the formation of carbon dioxide and water, avoiding unwanted products. Numerous semiconductors (isolated or in heterostructure form) are used as photoactive and photoelectroactive materials, such as zinc oxide, 11,13 titanium dioxide, 4,5 bismuth vanadate, 14,15 silver phosphate/ bismuth oxobromide, 16 reduced graphene oxide/graphitic carbon nitride, 17 reduced graphene oxide/ferric oxide, 12 cerium dioxide-ferric oxide, 18 copper (I) oxide-copper (II) oxide, 19 p-silver sulphide/n-silver indium sulphide 20 and copper pyrovanadate, 10 among others. In semiconductor materials, the charge carriers' generation during an electronic excitation with a specific wavelength will stimulate the electron density in the conduction band (CB) and the density of the holes in the valence band (VB).…”