As a well-known semiconductor that can catalyse the oxygen evolution reaction, TiO₂ has been extensively investigated for its solar photoelectrochemical water properties. Unmodified TiO₂ shows some issues, particularly with respect to its photoelectrochemical performance. In this paper, we present a strategy for the controlled deposition of controlled amounts of GaO_xN_y cocatalysts on TiO₂ 1D nanowires (TiO₂@GaO_xN_y core–shell) using atomic layer deposition. We show that this modification significantly enhances the photoelectrochemical performance compared to pure TiO₂ NW photoanodes. For our most active TiO₂@GaO_xN_y core–shell nanowires with a GaO_xN_y thickness of 20 nm, a photocurrent density up to 1.10 mA cm⁻² (at 1.23 V vs. RHE) under AM 1.5 G irradiation (100 mW cm⁻²) has been achieved, which is 14 times higher than that of unmodified TiO₂ NWs. Furthermore, the band gap matching with TiO₂ enhances the absorption of visible light over unmodified TiO₂ and the facile oxygen vacancy formation after the deposition of GaO_xN_y also provides active sites for water activation. Density functional theory studies of model systems of GaO_xN_y–modified TiO₂ confirm the band gap reduction, high reducibility and ability to activate water. The highly efficient and stable systems of TiO₂@GaO_xN_y core–shell nanowires with ALD deposited GaO_xN_y demonstrate a good strategy for the fabrication of core–shell structures that enhance the photoelectrochemical performance of readily available photoanodes.

中文翻译：

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通过原子层沉积用GaOxNy修饰一维TiO2纳米线，以增强TiO2 @ GaOxNy核壳纳米线的光电化学性能

作为能够催化氧释放反应的众所周知的半导体，TiO ₂的太阳能光电化学水性质已被广泛研究。未改性的TiO ₂表现出一些问题，特别是在其光电化学性能方面。在本文中，我们提出了一种利用原子层沉积法在TiO ₂ 1D纳米线上（TiO ₂ @GaO _x N _y核-壳）控制沉积受控量的GaO _x N _y助催化剂的策略。我们表明，与纯TiO ₂ NW光阳极相比，这种修饰显着增强了光电化学性能。对于我们最活性的TiO_2条@GaO _x N _y核-壳纳米线，GaO _x N _y厚度为20 nm，在AM 1.5 G辐照下（100 mW cm ^-2），光电流密度高达1.10 mA cm ^-2（在1.23 V vs. RHE时））已实现，比未改性的TiO ₂ NW高14倍。此外，与TiO ₂匹配的带隙增强了未改性TiO ₂的可见光吸收，并在沉积GaO _x N _y之后形成了容易形成的氧空位还提供了活化水的活性部位。GaO _x N _y改性的TiO ₂模型系统的密度泛函理论研究证实了带隙减小，高还原性和活化水的能力。TiO 2的高效和稳定的系统₂ @GaO _X Ñ _ý芯-壳纳米线沉积ALD高_X Ñ _ÿ证明对能够增强容易获得的光阳极的光电化学性能核-壳结构的制造一个好策略。