Complementary effect of components in a hybrid photocatalyst is an essential factor for improving solar energy-conversion efficiency, yet the underlying correlation between nitrogen-doped carbon quantum dots (N-CQDs) and oxygen vacancy (OV) is still ambiguous. Herein, using BiOBr nanosheets as model photocatalyst, we studied the specific roles of N-CQDs and OV in antibiotic photodegradation over full-spectrum. Electrons were overwhelmingly collected on N-CQDs rather than OV, achieving prominent separation of photo-excitons. However, OV could extend the congenitally optical absorption boundary of BiOBr to maximum utilizing the up-converted photons by N-CQDs. Moreover, active radical tests revealed that N-CQDs mainly regulated the single-electron reduction of dissolved oxygen to produce superoxide radicals (O₂⁻) and OV mainly drove the robust H₂O₂ generation via two-electron reduction of the chemisorbed oxygen molecules. Although partial O₂⁻ were consumed as the raw of H₂O₂, a Photo-Fenton like reaction could transform H₂O₂ into hydroxyl radicals (OH) to provide more powerful oxidizing force. This work provides an in-depth understanding on the complementary roles of N-CQDs and OV and is helpful for designing highly efficient metallic oxide catalysts for photocatalytic pollutant removal.

杂化光催化剂中各组分的互补作用是提高太阳能转化效率的必要因素，但氮掺杂碳量子点（N-CQDs）与氧空位（OV）之间的潜在相关性仍然不明确。在本文中，我们使用BiOBr纳米片作为模型光催化剂，研究了N-CQD和OV在全光谱抗生素光降解中的特定作用。电子被压倒在N-CQD而非OV上，从而实现了光激子的显着分离。但是，OV可以利用N-CQD上转换的光子将BiOBr的本征光吸收边界扩展到最大。此外，活性自由基测试表明，N-CQD主要调节溶解氧的单电子还原以产生超氧自由基（O ₂⁻）和OV主要通过化学吸附的氧分子的两电子还原驱动强劲的H ₂ O ₂生成。虽然局部ö ₂ ^-被消耗为H的原料₂ Ô ₂，光芬顿样反应可能改变ħ ₂ ö ₂为羟基自由基（OH），以提供更强大的氧化力。这项工作提供了对N-CQD和OV的互补作用的深入理解，并有助于设计用于去除光催化污染物的高效金属氧化物催化剂。