In this study, we have developed a facile chemical bath deposition (CBD) method to grow p-type Cu₂O nanoparticles on n-type TiO₂ nanowire arrays (TiO₂ NWAs) to fabricate TiO₂/Cu₂O core/shell heterojunction nanowire arrays (TiO₂/Cu₂O core/shell NWAs). When used as photoelectrode, the fabricated TiO₂/Cu₂O core/shell NWAs show improved photoelectrochemical (PEC) water splitting activity to pure TiO₂ NWAs. The effects of the CBD cycle times on the PEC activities have been studied. The TiO₂/Cu₂O core/shell heterojunction nanowire array photoelectrode prepared by cycling 5 times in the CBD process achieves the highest photocurrent of 2.5 mA cm⁻², which is 2.5 times higher than that of pure TiO₂ NWAs. In addition, the H₂ generation rate of this photoelectrode reaches to 32 μmol h⁻¹ cm⁻², 1.7 times higher than that of pure TiO₂ NWAs. Furthermore, the TiO₂/Cu₂O core/shell heterojunction nanowire array photoelectrode shows excellent photostability and achieves a stable photocurrent of over 2.3 mA cm⁻² during long light illumination time of 5 h. The enhanced photocatalytic activity of TiO₂/Cu₂O core/shell heterojunction nanowire array photoelectrode is attributed to the synergistic actions of TiO₂ and Cu₂O for improving visible light harvesting, and efficient transfer and separation of photogenerated electrons and holes.

在这项研究中，我们已经开发了一种简便的化学浴沉积（CBD）方法，以在n型TiO ₂纳米线阵列（TiO ₂ NWAs）上生长p型Cu ₂ O纳米颗粒，以制造TiO ₂ / Cu ₂ O核/壳异质结纳米线阵列（TiO ₂ / Cu ₂ O核/壳NWA）。当用作光电极时，制成的TiO ₂ / Cu ₂ O核/壳NWA表现出对纯TiO ₂ NWA改善的光电化学（PEC）水分解活性。已经研究了CBD循环时间对PEC活性的影响。TiO ₂ / Cu ₂通过在CBD过程中循环5次而制备的O核/壳异质结纳米线阵列光电极实现了2.5 mA cm ^-2的最高光电流，这是纯TiO ₂ NWA的2.5倍。另外，该光电极的H ₂产生率达到32μmolh ^-1  cm ^-2，是纯TiO ₂ NWA的1.7倍。此外，TiO ₂ / Cu ₂ O核/壳异质结纳米线阵列光电极表现出优异的光稳定性，并且在5小时的长时间光照下实现了超过2.3mA cm ^-2的稳定光电流。TiO的增强的光催化活性₂ / Cu ₂ O核/壳异质结纳米线阵列光电极归因于TiO ₂和Cu ₂ O的协同作用，以改善可见光的收集，以及光生电子和空穴的有效转移和分离。