Severe bulk charge recombination, sluggish oxygen evolution rection (OER) kinetics and poor visible light harvesting are still the technical bottlenecks of famous TiO₂ photoanode for photoelectrochemical (PEC) water splitting. Here, a novel CQDs/E-TiO₂ photoanode was designed based on the accurately electrochemical reduction of TiO₂ (E-TiO₂, Ti⁴⁺ + e^- → Ti³⁺) and further modification of oxygen vacancy (O_V)-rich carbon quantum dots (CQDs) for synergistically improving PEC performance. The electrochemical reduction creates modreate O_V in TiO₂, which increase the majority carrier density and provide photoinduced charge traps for sharply increasing the bulk charge separation efficiency (η_bulk). The CQDs modification dramatically improves the surface charge transfer efficiency (η_surface) by serving as oxygen evolution catalysts (OECs), because the abundant O_V in CQDs greatly promote the OER kinetics. Additionally, the visible light harvesting of TiO₂ is significantly improved after CQDs modification. Near-complete bulk charge separation (η_bulk = 94.7%) is achieved for E-TiO₂ at 1.23 V vs. RHE (V_RHE), which is 4.0 times higher than that of TiO₂. The CQDs/E-TiO₂ shows the η_surface of 56.0% at 0.40 V_RHE, which is 7.2 times higher than E-TiO₂. Therefore, the CQDs/E-TiO₂ exhibits remarkable photocurrent densities of 1.50 mA cm^-2 at 0.60 V_RHE and 2.55 mA cm^-2 at 1.23 V_RHE, which are 27.0 and 10.0 times higher than TiO₂, 3.5 and 1.5 times higher than E-TiO₂, respectively.

严重的体电荷复合、缓慢的析氧反应（OER）动力学和较差的可见光捕获仍然是著名的用于光电化学（PEC）水分解的TiO _{2 光}阳极的技术瓶颈。在此，基于 TiO ₂ (E-TiO ₂ , Ti ⁴⁺ + e ^- → Ti ³⁺ )的精确电化学还原和氧空位 ( _OV )- 的进一步改性，设计了一种新型 CQDs/E-TiO _{2 光}阳极富碳量子点 (CQD) 可协同提高 PEC 性能。电化学还原在 TiO _{2 中}产生适度的 O _V，这增加了多数载流子密度和用于急剧提高堆积的电荷分离效率（光诱导提供电荷陷阱η_散装）。该变形例CQDs显着地提高表面电荷转移效率（η_表面由作为析氧催化剂（嗅鞘细胞）），因为丰富Ó _V在CQDs极大地促进了OER动力学。此外，在 CQDs 改性后，TiO ₂的可见光捕获得到显着改善。接近完全散装电荷分离（η_散装= 94.7％）为E-的TiO实现₂ 1.23 V，相对于RHE（V _RHE），这比的TiO更高4.0倍₂. CQDs/E-TiO ₂在0.40 V _{RHE 下}显示56.0%的η_表面，比E-TiO ₂高7.2倍。因此，CQDs/E-TiO ₂表现出显着的光电流密度，在 0.60 V _{RHE 下}为 1.50 mA cm ^-2，在 1.23 V _{RHE 下}为2.55 mA cm ^-2，分别是 TiO _{2 的}27.0 和 10.0 倍，分别高出3.5 和 1.5 倍分别比 E-TiO ₂。