Design and fabrication of polyaniline/Bi2MoO6 nanocomposites for enhanced visible-light-driven photocatalysis

Abstract

The facile synthesis of polyaniline/Bi₂MoO₆ (PANI_x/Bi₂MoO₆) nanocomposites for visible-light-driven degradation of rhodamine B (RhB) was developed via in situ polymerization of PANI on the surface of Bi₂MoO₆ nanosheets as robust photocatalysts. The molecular PANI layers covered the surface of flower-like Bi₂MoO₆ microspheres consisting of ultrathin nanosheets (13.8 ± 1.6 nm) and exerted no impact on the intrinsic crystallinity of Bi₂MoO₆. The PANI/Bi₂MoO₆ exhibited enhanced visible light absorbance, improved photoelectrochemical performance and remarkably increased photocatalytic efficiency in the degradation of RhB. The synergistic effect of the well-matched band structures of Bi₂MoO₆ and PANI coupled with the molecular PANI layers for excellent hole transfer and accessible active sites contributed to the enhanced separation efficiency of photogenerated charge carriers and the boosted photocatalytic activity for RhB removal. Mechanism studies indicated that the photoinduced holes and superoxide radicals played essential roles in the enhanced photocatalytic performance. The optimized photodegradation rate for RhB was up to ∼100% during 120 min in the case of PANI_0.5/Bi₂MoO₆, which revealed the first-order kinetics with a high apparent rate constant of 0.0335 min⁻¹ and acceptable recycling stability. This work sheds light on the application of Bi₂MoO₆-based photocatalysts with superior photocatalytic activity in environmental remediation.