Hydrogen (H₂) sensing is crucial in a wide variety of areas, such as industrial, environmental, energy and biomedical applications. However, engineering a practical, reliable, fast, sensitive and cost-effective hydrogen sensor is a persistent challenge. Here we demonstrate hydrogen sensing using aluminum-doped zinc oxide (AZO) metasurfaces based on optical read-out. The proposed sensing system consists of highly ordered AZO nanotubes (hollow pillars) standing on a SiO₂ layer deposited on a Si wafer. Upon exposure to hydrogen gas, the AZO nanotube system shows a wavelength shift in the minimum reflectance by ∼13 nm within 10 minutes for a hydrogen concentration of 4%. These AZO nanotubes can also sense the presence of a low concentration (0.7%) of hydrogen gas within 10 minutes. Their rapid response time even for a low concentration, the possibility of large sensing area fabrication with good precision, and high sensitivity at room temperature make these highly ordered nanotube structures a promising miniaturized H₂ gas sensor.

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使用铝掺杂的 ZnO 超表面进行氢气传感

氢 (H ₂ ) 传感在工业、环境、能源和生物医学应用等广泛领域至关重要。然而，设计一种实用、可靠、快速、灵敏且具有成本效益的氢传感器是一项持久的挑战。在这里，我们演示了使用基于光学读出的铝掺杂氧化锌 (AZO) 超表面进行氢传感。所提出的传感系统由高度有序的 AZO 纳米管（空心柱）组成，位于 SiO _2上层沉积在硅晶片上。在氢气浓度为 4% 的情况下，AZO 纳米管系统在 10 分钟内显示出最小反射率的波长偏移约 13 nm。这些 AZO 纳米管还可以在 10 分钟内感应到低浓度 (0.7%) 氢气的存在。即使在低浓度下它们的快速响应时间、高精度的大传感区域制造的可能性以及室温下的高灵敏度使得这些高度有序的纳米管结构成为有前途的小型化 H ₂气体传感器。