It is still challenging to produce superoxide and hydroxyl radicals through activating molecular oxygen under broad-spectrum light in environmental photocatalysis. In this work, nitrogen-doped graphene quantum dots (N-GQDs) modified BiO_2-x nanosheets were successfully fabricated and exhibited superior performance in light-harvesting, electron-hole pair separation, and full-spectrum driven molecular oxygen activation. The hybridized photocatalyst with a N-GQDs weight ratio of 0.4wt% (GBO-0.4) exhibited an excellent photocatalytic activity toward tetracycline degradation with a 4.0-fold, 2.9-fold and 5.5-fold higher reaction rate under full-spectrum, visible and near-infrared light irradiations than that of pure BiO_2-x, respectively. The enhanced photocatalytic performance was ascribed to the electron collection effect and up-conversion photoluminescence properties of the N-GQDs as well as the synergistic effects of the developed nanojunction. Efficient molecular oxygen activation was achieved via the construction of a bulk-to-surface channel between BiO_2-x and N-GQDs. DFT calculations were also used to explore the geometric and electronic structure variations of BiO_2-x after the introduction of N-GQDs. The high photostability and mineralization ability toward tetracycline degradation confirm the promising application prospects of the N-GQDs/BiO_2-x photocatalyst. This work provides a rational strategy for designing 0D/2D nanoscale heterostructure photocatalysts with improved full-spectrum photoactivity for environmental applications.

在环境光催化下，通过在广谱光下活化分子氧来产生超氧化物和羟基自由基仍然具有挑战性。在这项工作中，成功地制备了氮掺杂石墨烯量子点（N-GQDs）修饰的BiO _2-x纳米片，并在光收集，电子-空穴对分离和全光谱驱动的分子氧活化方面表现出优异的性能。N-GQDs重量比为0.4wt％（GBO-0.4）的杂化光催化剂对四环素降解表现出优异的光催化活性，在全光谱，可见光和可见光下的反应速率分别高4.0倍，2.9倍和5.5倍。比纯BiO _2-x的近红外光照射， 分别。增强的光催化性能归因于N-GQD的电子收集效应和上转换光致发光特性，以及发达的纳米结的协同效应。通过在BiO _2-x和N-GQD之间建立从表面到表面的通道，可以实现有效的分子氧活化。在引入N-GQD之后，DFT计算还用于探索BiO _2-x的几何和电子结构变化。对四环素降解的高光稳定性和矿化能力证实了N-GQDs / BiO _2-x的应用前景光催化剂。这项工作为设计用于环境应用的具有改善的全光谱光活性的0D / 2D纳米级异质结构光催化剂提供了合理的策略。