Developing Z-scheme Bi₂MoO₆@α-MnO₂ beaded core-shell heterostructure in photoelectrocatalytic treatment of organic...

Photoelectrocatalysis (PEC) oxidation technology with the combination of electrocatalysis and photocatalysis is an ideal candidate for treatment of dyeing wastewater containing multifarious intractable organic compounds with high chroma. Constructing high-quality heterojunction photoelectrodes can effectively suppress the recombination of photo-generated carriers, thereby achieving efficient removal of pollution. Herein, a beaded Bi₂MoO₆@α-MnO₂ core-shell architecture with tunable hetero-interface was prepared by simple hydrothermal-solvothermal process. The as-synthesized Bi₂MoO₆@α-MnO₂ had larger electrochemically active surface area, smaller charge transfer resistance and negative flat band potential, and higher separation efficiency of e^-/h⁺ pairs than pure α-MnO₂ or Bi₂MoO₆. It is noteworthy that the as-synthesized Bi₂MoO₆@α-MnO₂ showed Z-scheme heterostructure as demonstrated by the free radical quenching experiments. The optimized Bi₂MoO₆@α-MnO₂-2.5 exhibited the highest degradation rate of 88.64% in 120 min for reactive brilliant blue (KN-R) and accelerated stability with long-term(∼10000s) at the current density of 50 mA cm^-2 in 1.0 mol L^-1 H₂SO₄ solution. This study provides valuable insights into the straightforward preparation of heterogeneous electrodes, offering a promising approach for the treatment of wastewater in various industrial applications.