Bi₂Se₃, Bi₂Te₃ quantum dots-sensitized rutile TiO₂ nanorod arrays for enhanced solar photoelectrocatalysis in azo dye degradation

Abstract

Abstract Rutile TiO 2 nanorod arrays vertically aligned on conductive fluorine-doped tin oxide glass are optimized for photocatalysis in terms of the density and diameter of nanorods by tuning the concentration of Ti precursor and reaction time during the hydrothermal process. Quantum dots (QDs) of V 2 VI 3 ( V = Bi; VI = Se, Te) topographic insulators are then employed as sensitizers to enhance the visible-light response of TiO 2 . Electrochemical measurements show that the decoration of Bi 2 Se 3 or Bi 2 Te 3 significantly increases the photocurrent due to the enhanced light harvesting properties and the charge carrier separation capability mediated by the topographic isolation effect of V 2 VI 3 QDs. Photoelectrocatalytic (PEC) activity evaluation is conducted towards the decoloration of azo dyes, including methyl orange and methylene blue under the sunlight irradiation. The elaborated Bi 2 Se 3 /TiO 2 nanorod array exhibits the superior PEC performances, presenting shows great potentials in environmental remediation.