Fast and reliable semiconductor hydrogen sensors are crucially important for the large-scale utilization of hydrogen energy. One major challenge that hinders their practical application is the elevated temperature required, arising from undesirable surface passivation and grain-boundary-dominated electron transportation in the conventional nanocrystalline sensing layers. To address this long-standing issue, in the present work, we report a class of highly reactive and boundary-less ultrathin SnO₂ films, which are fabricated by the topochemical transformation of 2D SnO transferred from liquid Sn–Bi droplets. The ultrathin SnO₂ films are purposely made to consist of well-crystallized quasi-2D nanograins with in-plane grain sizes going beyond 30 nm, whereby the hydroxyl adsorption and grain boundary side-effects are effectively suppressed, giving rise to an activated (101)-dominating dangling-bond surface and a surface-controlled electrical transportation with an exceptional electron mobility of 209 cm² V^–1 s^–1. Our work provides a new cost-effective strategy to disruptively improve the gas reception and transduction of SnO₂. The proposed chemiresistive sensors exhibit fast, sensitive, and selective hydrogen sensing performance at a much-reduced working temperature of 60 °C. The remarkable sensing performance as well as the simple and scalable fabrication process of the ultrathin SnO₂ films render the thus-developed sensors attractive for long awaited practical applications in hydrogen-related industries.

中文翻译：

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具有表面激活二维纳米颗粒的超薄无边界 SnO2 薄膜可实现快速、灵敏的氢气传感


快速可靠的半导体氢传感器对于氢能的大规模利用至关重要。阻碍其实际应用的一个主要挑战是所需的高温，这是由于传统纳米晶传感层中不良的表面钝化和晶界主导的电子传输引起的。为了解决这个长期存在的问题，在目前的工作中，我们报告了一类高反应性和无边界超薄 SnO ₂ 薄膜，该薄膜是通过从液体 Sn 转移的 2D SnO 的拓扑化学转变而制成的。双滴。超薄 SnO ₂ 薄膜特意由晶化良好的准二维纳米颗粒组成，面内晶粒尺寸超过 30 nm，从而有效抑制羟基吸附和晶界副作用，从而得到上升到活化的 (101) 主导的悬空键表面和表面控制的电传输，其电子迁移率高达 209 cm ² V ^–1 s ^–1 .我们的工作提供了一种新的具有成本效益的策略，可以颠覆性地改善 SnO ₂ 的气体接收和转导。所提出的化学电阻传感器在大幅降低的 60 °C 工作温度下表现出快速、灵敏和选择性的氢传感性能。超薄 SnO ₂ 薄膜卓越的传感性能以及简单且可扩展的制造工艺使得由此开发的传感器对于氢相关行业期待已久的实际应用具有吸引力。