2D/1D Bi12O17Cl2/β-Bi2O3 heterojunction photocatalysts with boosted photocatalytic performance

Abstract

Novel 2D/1D Bi₁₂O₁₇Cl₂/β-Bi₂O₃ heterostructures were synthesized by calcining Bi(OHC₂O₄)·2H₂O/BiOCl precursors. Bi₁₂O₁₇Cl₂ nanosheets grow vertically on the β-Bi₂O₃ rods by crystallographically oriented epitaxial nucleation and growth, which increases the interface quality and then provides the smallest penetration barrier for electron–hole pair transfer at interfaces. The photocatalytic results show that Bi₁₂O₁₇Cl₂/β-Bi₂O₃ displays higher photocatalytic activity than β-Bi₂O₃ porous rods and Bi₁₂O₁₇Cl₂ nanosheets for degrading methyl orange (MO) and phenol under solar light irradiation. This outstanding photocatalytic activity is ascribed to the formation of a 2D/1D Bi₁₂O₁₇Cl₂/β-Bi₂O₃ heterostructure. This unique configuration results in the exposure of almost the entire surface of the 2D Bi₁₂O₁₇Cl₂ nanosheets and increases the charge separation and transfer rate. Radical scavenger experiments prove that the photogenerated holes and ˙O₂⁻ play key roles in the photodegradation process.