Defect-rich ultrathin heterovalent tin oxide (Sn₂O₃) nanosheets with dominant polar (100) facets were synthesized via a facile hydrothermal method for the first time. The structure, morphology, chemical state, bandgap, defects, and specific surface area of these Sn₂O₃ nanosheets were characterized by XRD, FE-SEM, TEM, XPS, UV–Vis, PL, N₂-adsorption, respectively. Taking inspiration from the morphology, defects, and exposed facets that facilitate adsorption-interaction of molecules on the surface, gas and humidity sensors were fabricated based on Sn₂O₃ nanosheets. The gas sensor response to 200 ppm ethanol at 200 °C is as high as 70.1, and response and recovery times are only 6 s and 3 s, respectively. At room temperature, the humidity sensor exhibits a response up to 2.76 × 10³ with a small humidity hysteresis of 1.95%, and the response and recovery times are divided into 27 s and 124 s, respectively. Additionally, both gas and humidity sensors demonstrate excellent repeatability and stability. Finally, gas and humidity sensing mechanisms of the Sn₂O₃ sensor have been discussed. This work provides a practical candidate for gas and humidity sensors and further develops a new promising application for heterovalent metal oxides in electrical sensory devices.

首次通过简便的水热法合成了具有主要极性 (100) 晶面的富含缺陷的超薄异价氧化锡 (Sn ₂ O ₃ ) 纳米片。这些Sn ₂ O ₃纳米片的结构、形貌、化学状态、带隙、缺陷和比表面积分别通过XRD、FE-SEM、TEM、XPS、UV-Vis、PL、N ₂吸附表征。受形貌、缺陷和暴露面的启发，这些表面促进了分子在表面上的吸附相互作用，基于 Sn ₂ O ₃制造了气体和湿度传感器纳米片。气体传感器在 200 °C 下对 200 ppm 乙醇的响应高达 70.1，响应时间和恢复时间分别仅为 6 s 和 3 s。在室温下，湿度传感器表现出高达 2.76 × 10 ³的响应，具有 1.95% 的小湿度滞后，响应时间和恢复时间分别分为 27 s 和 124 s。此外，气体和湿度传感器均表现出出色的可重复性和稳定性。最后，讨论了 Sn ₂ O ₃传感器的气体和湿度传感机制。这项工作为气体和湿度传感器提供了一个实用的候选者，并进一步开发了异价金属氧化物在电传感设备中的新应用。