All-vanadium photoelectrochemical flow cell, which combines the vanadium redox flow battery and the photoelectrochemical flow cell, is a promising technology to store solar energy in reversible redox pairs. The development of a high-performance photoanode is vital to promote the storage of solar energy. In this work, we developed a self-doped TiO₂ photoanode and applied it to a microfluidic all-vanadium photoelectrochemical flow cell (μVPFC). The self-doped TiO₂ photoanode was simply prepared by annealing the TiO₂ photoanode with NaBH₄ in the nitrogen atmosphere, by which the self-dopant led to the formation of a disordered layer on the surface and created a mid-band. As a result, the light absorption region was extended and the electron-hole pair separation efficiency was enhanced, promoting the capability of the μVPFC with the self-doped TiO₂ photoanode. The superiority of the self-doped TiO₂ photoanode was confirmed by its excellent photoelectrochemical performance and vanadium ion conversion rate. The μVPFC with the self-doped TiO₂ photoanode yielded an average photocurrent density as high as 0.064 mA·cm⁻² in 6-h operation, which was much higher than the reported TiO₂ and Ti₂O₃ photoanodes and presented the improvements by approximately 167% and 60%, respectively. In addition, intensifying the intensity of light and concentration of vanadium ion enabled the performance of the μVPFC with the self-doped TiO₂ photoanode to be promoted.

将钒氧化还原液流电池和光电化学液流电池相结​​合的全钒光电化学液流电池是一种以可逆氧化还原对存储太阳能的有前途的技术。高性能光阳极的开发对于促进太阳能的存储至关重要。在这项工作中，我们开发了一种自掺杂的 TiO _{2 光}阳极并将其应用于微流体全钒光电化学流通池 (μVPFC)。自掺杂 TiO _{2 光}阳极通过将 TiO _{2 光}阳极与 NaBH ₄退火来简单地制备在氮气氛中，自掺杂剂导致在表面上形成无序层并产生中带。结果，扩大了光吸收区域，提高了电子-空穴对分离效率，提高了具有自掺杂 TiO _{2 光}阳极的 μVPFC 的性能。自掺杂TiO _{2 光}阳极的优越性通过其优异的光电化学性能和钒离子转化率得到证实。带有自掺杂 TiO ₂光阳极的 μVPFC在 6 小时运行中产生高达 0.064 mA·cm ^-2的平均光电流密度，远高于报道的 TiO ₂和 Ti ₂ O ₃光阳极，并分别显示了大约 167% 和 60% 的改进。此外，增强光强度和钒离子浓度能够促进具有自掺杂 TiO _{2 光}阳极的 μVPFC 的性能。