Bi-based semiconductors have been regarded to be an ideal platform in photocatalytic CO₂ reduction to fuels. However, the insufficient charge transfer efficiency greatly restricts their practical application. Herein, we fabricated 1D/2D hierarchical heterostructures by the hybridization of Bi₄O₅Br₂ and rod-like MOF-derived MoS₂ anchored in nitrogen-doped porous carbon (NPC-MoS₂) using Mo-MOF as a precursor followed by sulfidation and typical solvothermal process. Compared to pristine Bi₄O₅Br₂ nanosheet and NPC-MoS₂ nanorod, the 5 wt% NPC-MoS₂@Bi₄O₅Br₂ p-n heterojunction exhibits distinctly enhanced photocatalytic activity under light illumination due to the increased light absorption capability and more effective charge transfer efficiency. X-ray photoelectron spectroscopy and photoelectrochemical analysis imply that a built-in electric field on interfaces is created to form p-n heterojunctions which drive the photoinduced electrons transferred from NPC-MoS₂ to Bi₄O₅Br₂. Finally, the type-II charge transfer mechanism is proposed which promotes separation of the charges and provides suitable conduction band to reduce CO₂ much efficiently. In a word, this work provides a new insight into the establishment of hierarchical p-n heterostructures for photocatalysis.

Bi基半导体被认为是光催化CO ₂还原为燃料的理想平台。然而，电荷转移效率不足极大地限制了它们的实际应用。在此，我们使用 Mo-MOF 作为前驱体，通过Bi ₄ O ₅ Br ₂和棒状 MOF 衍生的 MoS 2的杂化制造了 1D/2D 分级异质结构，该MoS ₂锚定在氮掺杂多孔碳 (NPC-MoS ₂ ) 中。硫化和典型的溶剂热过程。与原始 Bi ₄ O ₅ Br ₂纳米片和 NPC-MoS ₂纳米棒相比，5 wt% NPC-MoS ₂ @Bi_{由于增加的光吸收能力和更有效的电荷转移效率， 4} O ₅ Br ₂ p-n异质结在光照下表现出明显增强的光催化活性。X 射线光电子能谱和光电化学分析表明，在界面上产生了内置电场以形成pn异质结，从而驱动光生电子从 NPC-MoS ₂转移到 Bi ₄ O ₅ Br ₂。最后，提出了促进电荷分离并提供合适的导带以减少CO _{2的II型电荷转移机制。}效率很高。总之，这项工作为建立用于光催化的分级pn异质结构提供了新的见解。