Bicarbonate-triggered in-situ epitaxial construction of lattice matched NaBiO3/Bi2O2CO3 Z-scheme heterojunction for enhanced photocatalytic degradation of organic pollutants: Boosted carrier separation and mechanism insight

Conventional methods often construct heterojunctions with lattice mismatch and disordered interfaces, suppressing interfacial charge-transfer and weakening photocatalytic activity. Although epitaxial construction could obtain lattice-matched heterojunctions and then boost their carrier separation, constructing such structures under mild conditions remains challenging. Herein, we successfully prepare a lattice matched NaBiO 3 /Bi 2 O 2 CO 3 (NBO/BOC) of 95.8% by a facile bicarbonate (HCO 3 - )-triggered in-situ epitaxial strategy, which removes 98.2% metronidazole, representing an 8.25-fold enhancement over the HCO 3 - -free control, with an apparent reaction rate constant of 0.004   min -1 . Detailed characterizations and experiments results demonstrate that this high removal activity derives from the highly lattice-matched of NBO/BOC heterojunction. That is, the lattice-matched heterointerface in NBO/BOC ensures efficient Z-scheme band coupling and enhances interfacial charge transfer under the coordination of the built-in electric field, boosting photocatalytic degradation activity of the pollutant. These findings demonstrate a sustainable strategy that leverages an inherent wastewater component to self-construct efficient photocatalytic heterojunctions for pollutant degradation.