Refractory organic pollutants' degradation efficiency strongly depends on the amount of intermediate active species (hydroxyl radical and superoxide radical) in the photoelectrocatalytic (PEC) process. Here, the various amount of Sn₃O₄ nanosheets is adhered to the surface of Co₃O₄ nanowires by a simple hydrothermal process to assemble the Co₃O₄-Sn₃O₄ hierarchical nanoflower-tree architecture. The as-obtained Co₃O₄-Sn₃O₄-2.0 (2 mmol tin salt precursor) photoelectrodes exhibited superior PEC dye degradation efficiency than bare Co₃O₄ photoelectrode because the Co₃O₄-Sn₃O₄-2.0 hierarchical architecture has large electrochemical active, fast interfacial carrier transport, low electrochemical resistance, a proper bandgap, high electron-hole separation efficiency, and electron-deficient surface. Especially, Co₃O₄-Sn₃O₄-2.0 hierarchical architecture can promote the generation of intermediate active species (hydroxyl radical and superoxide radical) as the demonstration from the energy band structures, which play the predominant role in the PEC process. Additionally, the electron-deficient surface enhances the interaction with active species and increases stability during the PEC process. Overall, Co₃O₄-Sn₃O₄-2.0 architecture demonstrated the best PEC degradation rate (~87.5% in 2 h) and long-term stability (~13,000 s) in 0.1 mol/L Na₂SO₄ toward the accelerated degradation of reactive brilliant blue KN-R. The present work provides a feasible and straightforward route to obtain highly efficient PEC photoanode through a rational combination of Co₃O₄ and Sn₃O₄ with proper energy band tuning, which will guide other heterojunction designs.

难降解有机污染物的降解效率在很大程度上取决于光电催化（PEC）过程中中间活性物质（羟基自由基和超氧化物自由基）的数量。在此，通过简单的水热工艺将各种数量的Sn ₃ O ₄纳米片粘附到Co ₃ O ₄纳米线的表面，以组装Co ₃ O ₄ -Sn ₃ O ₄分层纳米花树结构。所获得的Co ₃ O ₄ -Sn ₃ O ₄ -2.0（2 mmol锡盐前体）光电极表现出比裸Co优异的PEC染料降解效率。₃ O ₄光电极，因为Co ₃ O ₄ -Sn ₃ O ₄ -2.0分层结构具有大的电化学活性，快速的界面载流子传输，低的电化学电阻，适当的带隙，高的电子-空穴分离效率和电子不足的表面。特别地，Co ₃ O ₄ -Sn ₃ O ₄-2.0分层结构可以促进中间活性物质（羟基自由基和超氧化物自由基）的产生，这是从能带结构中证明的，它们在PEC过程中起主要作用。此外，缺电子的表面增强了与活性物质的相互作用，并增加了PEC过程中的稳定性。总体而言，Co ₃ O ₄ -Sn ₃ O ₄ -2.0体系在0.1 mol / L Na ₂ SO _4中表现出最佳的PEC降解率（2小时内约87.5％）和长期稳定性（约13,000 s）。促进活性艳蓝KN-R的加速降解。本工作为通过合理结合能带调谐的Co ₃ O ₄和Sn ₃ O ₄的合理组合提供了一种获得高效PEC光电阳极的可行而直接的途径，这将指导其他异质结设计。