Visible-light responsive ZnSe-anchored mesoporous TiO 2 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 TiO ₂ for visible-light-driven photocatalytic reduction of Cr(VI) ions. The 7.9 nm ZnSe nanoparticles were attached to TiO ₂ surfaces 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 m ² g ^-1 . The impregnation of ZnSe amended the visible-light absorption of TiO ₂ due 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/TiO ₂ was achieved at 177 μ mol min ^-1 . This photocatalytic activity is higher than the common Degussa P25 and pristine TiO ₂ by 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/TiO ₂ has also shown photocatalytic stability for five consecutive runs.
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