The development of functional microstructures with designed hierarchical and complex morphologies and large free active surfaces offers new potential for improvement of the pristine microstructures properties by the synergistic combination of microscopic as well as nanoscopic effects. In this contribution, dedicated methods of transmission electron microscopy (TEM) including tomography are used to characterize the complex hierarchically structured hybrid GaN/ZnO:Au microtubes containing a dense nanowire network on their interior. The presence of an epitaxially stabilized and chemically extremely stable ultrathin layer of ZnO on the inner wall of the produced GaN microtubes is evidenced. Gold nanoparticles initially trigger the catalytic growth of solid solution phase (Ga1- x Znx )(N1- x Ox ) nanowires into the interior space of the microtube, which are found to be terminated by AuGa-alloy nanodots coated in a shell of amorphous GaOx species after the hydride vapor phase epitaxy process. The structural characterization suggests that this hierarchical design of GaN/ZnO microtubes could offer the potential to exhibit improved photocatalytic properties, which are initially demonstrated under UV light irradiation. As a proof of concept, the produced microtubes are used as photocatalytic micromotors in the presence of hydrogen peroxide solution with luminescent properties, which are appealing for future environmental applications and active matter fundamental studies.

中文翻译：

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先进的混合GaN / ZnO纳米结构微管，用于由紫外线驱动的荧光微电机。

具有设计的层级和复杂形态以及大的自由活性表面的功能性微结构的发展，通过微观和纳米效应的协同组合，为改善原始微结构的性质提供了新的潜力。在此贡献中，包括断层扫描在内的透射电子显微镜（TEM）专用方法被用来表征内部包含密集纳米线网络的复杂的分层结构混合GaN / ZnO：Au微管。已证明在所生产的GaN微管的内壁上存在外延稳定且化学上极其稳定的ZnO超薄层。金纳米粒子最初会触发固溶相（Ga1- x Znx）（N1- x Ox）纳米线向微管内部空间的催化生长，发现它们在氢化物气相外延工艺之后被包覆在非晶态GaOx物种壳中的AuGa合金纳米点终止。结构表征表明，这种GaN / ZnO微管的分层设计可以提供显示改进的光催化性能的潜力，该性能最初在紫外线照射下得到了证明。作为概念证明，在具有发光特性的过氧化氢溶液的存在下，所生产的微管被用作光催化微电机，这对于将来的环境应用和活性物质基础研究具有吸引力。结构表征表明，这种GaN / ZnO微管的分层设计可以提供显示改进的光催化性能的潜力，该性能最初在紫外线照射下得到了证明。作为概念证明，在具有发光特性的过氧化氢溶液的存在下，所生产的微管被用作光催化微电机，这对于将来的环境应用和活性物质基础研究具有吸引力。结构表征表明，这种GaN / ZnO微管的分层设计可以提供显示改进的光催化性能的潜力，该性能最初在紫外线照射下得到了证明。作为概念证明，在具有发光特性的过氧化氢溶液的存在下，所生产的微管被用作光催化微电机，这对于将来的环境应用和活性物质基础研究具有吸引力。