The efficiency of hole extraction and transfer at electrode/electrolyte interface is one of the most important bottlenecks of BiVO₄ photoanodes for photoelectrochemical (PEC) water splitting. Here, a huge improvement of surface charge transfer efficiency (η_surface) of BiVO₄ photoanode was achieved by surface modification of oxygen vacancy-abundant carbon quantum dots (O_V-CQDs), in which the O_V-CQDs serve as superfast hole transport channel for the fact that the abundant O_V in O_V-CQDs could induce the outward driving forces for hole trapping and migration at electrode/electrolyte interface. The O_V-CQDs/BiVO₄ shows the η_surface value of 74.3% at 0.65 V vs. RHE (V_RHE), which is 7.1 and 3.3 times higher than BiVO₄ and CQDs/BiVO₄, respectively. Besides, the O_V-CQDs efficiently promote the bulk charge separation and UV-vis light harvesting of BiVO₄. Therefore, the O_V-CQDs/BiVO₄ exhibits remarkable photocurrent densities of 2.76 mA cm^-2 at 0.65 V_RHE and 4.01 mA cm^-2 at 1.23 V_RHE, which are 12.5 and 3.4 times higher than BiVO₄, 3.5 and 2.6 times higher than CQDs/BiVO₄, respectively.

电极/电解质界面的空穴提取和转移效率是BiVO _{4 光}阳极用于光电化学（PEC）水分解的最重要瓶颈之一。在这里，BiVO _{4 光}阳极的表面电荷转移效率（η_表面）的巨大提高是通过氧空位丰富的碳量子点（O _V -CQDs）的表面改性实现的，其中 O _V -CQDs 作为超快空穴传输O _V -CQDs 中丰富的 O _V可以诱导电极/电解质界面处空穴捕获和迁移的向外驱动力。O _V -CQDs/BiVO_图4显示了在0.65V时74.3%的η_表面值vs.RHE (V _RHE )，分别是BiVO ₄和CQDs/BiVO _{4 的}7.1和3.3倍。此外，O _V -CQDs 有效地促进了 BiVO ₄的体电荷分离和紫外可见光收集。因此，O _V -CQDs/BiVO ₄表现出显着的光电流密度，在0.65 V _{RHE 下}为2.76 mA cm ^-2，在1.23 V _{RHE 下}为4.01 mA cm ^-2，分别是BiVO _{4 的}12.5 倍和3.4 倍，分别是BiVO _{4 的}3.5 倍和2.6 倍。高于 CQDs/BiVO ₄， 分别。