Visible-light responsive ZnSe-anchored mesoporous TiO2 heterostructures for boosted photocatalytic reduction of Cr(VI)

The accumulation of Cr(VI) ions in water can cause serious influences on the environment and human health. This work reports a humble synthesis of ZnSe nanoparticles anchored to the sol-gel prepared TiO2for visible-light-driven photocatalytic reduction of Cr(VI) ions. The 7.9 nm ZnSe nanoparticles were attached to TiO2surfaces at a content of 1.0-4.0 wt% as experiential by TEM investigation. The designed nanocomposite unveiled mesostructured surfaces exhibiting surface areas of 176-210 m2g-1. The impregnation of ZnSe amended the visible-light absorption of TiO2due to the bandgap decrease from 3.14 to 2.90 eV. The photocatalytic reduction of Cr(VI) applying the optimized portion of 3.0 wt% ZnSe/TiO2was achieved at 177μmol min-1. This photocatalytic activity is higher than the common Degussa P25 and pristine TiO2by 20 and 30 times, respectively. The improved performance is signified by the efficient interfacial separation of charge carriers by the introduction of ZnSe. This innovative ZnSe/TiO2has also shown photocatalytic stability for five consecutive runs.