Synthesis of Cr 2O 3/TNTs nanocomposite and its photocatalytic hydrogen generation under visible light irradiation

Abstract

A novel Cr 2O 3/TNTs nanocomposite was prepared by loaded suitable amount of amorphous Cr 2O 3 on titanate nanotubes (TNTs) via hydrothermal reaction and impregnation process. XRD, SEM and TEM results demonstrated that the amorphous Cr 2O 3 nanoparticles were homogeneously dispersed on the surface of TNTs. The diffuse reflectance UV–visible absorption spectra exhibited that the spectral response of TNTs was extended to visible light region by coupled with Cr 2O 3. The 2.5Cr 2O 3/TNTs nanocomposite showed the highest activity of hydrogen generation by photocatalytic water-splitting under visible light irradiation ( λ > 400 nm). The high activity of H 2 evolution for Cr 2O 3/TNTs nanocomposites was associated with the donor level in the forbidden band of TNTs semiconductor provided by dopant Cr 3+ and a probably photocatalytic mechanism was proposed.