In this study, the GaN/ZnO heterojunction and ZnO–NiO p–n junction core/shell nanocolumns were fabricated based on GaN nanocolumns. During the water splitting measurements, the photocurrent of GaN/ZnO/NiO (GZN) nanocolumns is 2.1 times higher than that of GaN nanocolumns. The enhancement is mainly due to the heterojunction between GaN and ZnO and the p–n junction between ZnO and NiO, which build strong built-in electric fields to accelerate the separation of photogenerated carriers. Besides, the refractive index of NiO and ZnO is smaller than that of GaN, which can facilitate the light absorption of GZN nanocolumns and improve the water splitting performance. Our work has greatly improved the photocatalytic efficiency of GaN for water splitting applications.

中文翻译：

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使用GaN / ZnO / NiO核/壳纳米柱有效增强光催化水分解

在这项研究中，基于GaN纳米柱制造了GaN / ZnO异质结和ZnO-NiO p-n结核/壳纳米柱。在水分解测量期间，GaN / ZnO / NiO（GZN）纳米柱的光电流是GaN纳米柱的光电流的2.1倍。增强的主要原因是GaN和ZnO之间的异质结以及ZnO和NiO之间的p–n结，它们建立了强大的内置电场，从而加速了光生载流子的分离。另外，NiO和ZnO的折射率小于GaN的折射率，这可以促进GZN纳米柱的光吸收并改善水分解性能。我们的工作大大提高了GaN在水分解应用中的光催化效率。