Photoelectrochemical (PEC) water-splitting using solar energy holds great promise for the renewable energy future, and a key challenge in the development of industry viable PEC devices is the unavailability of high-efficient photoanodes. Herein, we designed a TiO₂ model photocatalyst with nano-groove pattern and different surface orientation using low-energy Ar⁺ irradiation and photoetching of TiO₂, and significantly improved the intrinsic activity for PEC water oxidation. High-resolution transmission electron microscopy directly manifests that the grooves consist of highly stepped surface with < 110 > steps and well-crystallized. Transient absorption spectroscopy reveals the groove surface that allows for increased recovery lifetime, which ensures promoted electron-hole separation efficiency. Surface photovoltage directly shows the carrier separation and transportation behaviors, verified by selective photodeposition, demonstrating the groove surface on TiO₂ contributes to electron-hole separation. This work proposes an efficient and scalable photoanode strategy, which potentially can open new opportunities for achieving efficient PEC water oxidation performance.

使用太阳能的光电化学 (PEC) 水分解为可再生能源的未来带来了广阔的前景，而开发工业可行的 PEC 设备的一个关键挑战是无法获得高效的光阳极。在此，我们设计了一种具有纳米凹槽图案和不同表面取向的 TiO ₂模型光催化剂，使用低能 Ar ⁺照射和 TiO ₂光刻，并显着提高了 PEC 水氧化的内在活性。高分辨率透射电子显微镜直接表明凹槽由具有<110>台阶且结晶良好的高度阶梯状表面组成。瞬态吸收光谱揭示了凹槽表面，可延长恢复寿命，从而确保提高电子-空穴分离效率。表面光电压直接显示载流子分离和传输行为，通过选择性光沉积验证，表明 TiO ₂上的凹槽表面有助于电子 - 空穴分离。这项工作提出了一种高效且可扩展的光阳极策略，这可能为实现高效的 PEC 水氧化性能开辟新的机会。