New BaTi[sub.0.96]Cu[sub.0.02]X[sub.0.02]O[sub.3] Photocatalysts for Dyes Effluent Remediation: Broad Visible Light Response

The problem of industrial dyes depollution has pushed the scientific research community to identify novel photocatalysts with high performance. Herein, new photocatalysts composed of BaTiO[sub.3], BaTi[sub.0.96]Cu[sub.0.04]O[sub.3], BaTi[sub.0.96]Cu[sub.0.02]V[sub.0.02]O[sub.3] and BaTi[sub.0.96]Cu[sub.0.02]Nb[sub.0.02]O[sub.3] powders were prepared by solid-state reaction. The structural analysis of the samples confirmed the formation of the BaTiO[sub.3] structure. The splitting of (002) and (200) planes verified the formation of the tetragonal phase. The XRD peaks shifted, and the unit cell volume expansion verified the substitution of the Ti[sup.4+] site by Cu[sup.2+], V[sup.4+] and Nb[sup.5+] ions. The morphological measurements showed that the addition of (Cu, V) and (Cu, Nb) ions changes the particles’ morphology of BaTiO[sub.3], reducing its grains size. After the incorporation of (Cu, V) and (Cu, Nb) ions, the band gap of BaTiO[sub.3] was reduced from 3.2 to 2.84 and 2.72 eV, respectively. The modification of BaTiO[sub.3] by (Cu, Nb) ions induced superior photocatalytic properties for methyl green and methyl orange with degradation efficiencies of 97% and 94% during 60 and 90 min under sunlight irradiation, respectively. The total organic carbon results indicated that the BaTi[sub.0.96]Cu[sub.0.02]Nb[sub.0.02]O[sub.3] catalyst has a high mineralization efficiency. In addition, it possesses a high stability during three cycles. The high photodegradation efficiency of Bi[sub.0.96]La[sub.0.02]Gd[sub.0.02]FeO[sub.3] was related to the wide-ranging visible light absorption.