Non-additional carbon source one-step synthesis of Bi₂O₂CO₃-based ternary composite for efficient Z-scheme...

Bi₂O₂CO₃-based ternary composite materials are generally synthesized by two- or multi-step method and special precursor of CO₃^2- is usually utilized in synthesis of Bi₂O₂CO₃, which are time-consuming, laborious and relatively costly. In this paper, for the first time, a facile one-step solvothermal method is used to fabricate Z-scheme Bi₂O₂CO₃/Bi/Bi₂WO₆ ternary composites. Interestingly, ethylene glycol not only acts as solvent for the reaction system, but also reduced Bi³⁺ into metallic Bi and itself is oxidized to CO₃^2-, which could construct Bi₂O₂CO₃. On this occasion, Bi₂O₂CO₃/Bi/Bi₂WO₆ ternary composites are obtained after one-step method. High resolution transmission electron microscopy clearly reveals each component in composites. The as-prepared samples could be applied in various photocatalytic activities. Under solar light irradiation, Bi₂O₂CO₃/Bi/Bi₂WO₆ composites exhibited prominent photodegradation performances for both ciprofloxacin and bisphenol A. Meanwhile, these composites could also be used in efficient photoreduction of CO₂. The efficient photocatalytic activity could be mainly ascribed to Z-scheme electron transfer mechanism in ternary composites, which is determined by surface redox reactions, active species trapping experiment, electron spin resonance spectrum.