Disentangling surface and bulk properties of Ta(3)N(5) photoanodes.

Surface and bulk defect characteristics critically influence the photoelectrochemical performance of Ta(3)N(5) photoanodes, with surface properties varying significantly by precursor chemistry.

• Why it matters: Understanding the distinct roles of surface and bulk defects is vital for designing stable, high-efficiency photoelectrodes, yet their individual contributions are often unclear.
• What they did: Depth-sensitive analyses of Ta(3)N(5) films prepared from different precursors revealed that surfaces are oxygen-enriched and structurally disordered, with defect densities depending on precursor chemistry, and surface treatments can improve performance.
• The result: Removing disordered surface layers enhances crystallinity, hydrophilicity, and stability, demonstrating that interfacial and defect engineering can lead to more durable, high-performance Ta(3)N(5) photoelectrodes.