In this work, a novel Bi₂S₃/Bi₅O₇I p-n heterojunction with three-dimensional rod-like nanostructure was successfully constructed through an in-situ topotactic ion exchange approach. A possible evolution mechanism from Bi₅O₇I nanobelts (NBs) into Bi₂S₃/Bi₅O₇I rod-like heterostructures (BSI RHs) was proposed, depicting the self-assembly process of internal Bi₅O₇I NBs and outside networks interwoven by Bi₂S₃ nanorods (NRs), which abided by the Ostwald ripening and epitaxial growth. Owing to the formation of p-n heterojunction and rich oxygen vacancies (OVs), the visible-light absorption ability and separation of photogenerated charge carriers of BSI RHs were highly promoted, leading to a greatly improved photocatalytic ability than that of Bi₂S₃ and Bi₅O₇I. BSI-1 exhibited the strongest photocatalytic performance, and almost all rhodamine B (RhB) and Pseudomonas aeruginosa (P. aeruginosa) can be thoroughly removed within 90 min. Moreover, a possible photocatalytic mechanism of BSI RHs was proposed based on the tests of active species trapping, electron spin resonance (ESR), photoelectrochemistry (PEC), and photoluminescence (PL) combined with the density functional theory (DFT) simulated computation, validating the dominating roles of ∙O₂⁻ and h⁺ during the photocatalytic process. This work is expected to motivate further efforts for developing novel heterostructures with highly efficient photocatalytic performances, which presents a promising application prospect in the fields of energy and environment.

在这项工作中，通过原位拓扑离子交换方法成功构建了具有三维棒状纳米结构的新型Bi ₂ S ₃ /Bi ₅ O ₇ I pn异质结。_{提出了从 Bi 5} O ₇ I 纳米带 (NBs) 到 Bi ₂ S ₃ /Bi ₅ O ₇ I 棒状异质结构 (BSI RHs)的可能演化机制，描述了内部 Bi ₅ O ₇ I NBs的自组装过程和外部网络由 Bi ₂ S ₃交织纳米棒（NRs），遵循奥斯特瓦尔德成熟和外延生长。由于pn异质结的形成和富氧空位（OVs），BSI RHs的可见光吸收能力和光生电荷载流子的分离得到了极大的促进，与Bi ₂ S ₃和Bi相比，光催化能力大大提高₅ O ₇ I. BSI-1 表现出最强的光催化性能，几乎所有的罗丹明 B (RhB) 和铜绿假单胞菌( P. aeruginosa) 可在 90 分钟内彻底清除。此外，基于活性物质捕获、电子自旋共振（ESR）、光电化学（PEC）和光致发光（PL）测试，结合密度泛函理论（DFT）模拟计算，提出了BSI RHs可能的光催化机理，验证了∙O ₂ ^-和 h ⁺在光催化过程中的主要作用。这项工作有望激发人们进一步努力开发具有高效光催化性能的新型异质结构，这在能源和环境领域具有广阔的应用前景。