Qu Fengdong, Zhang Shendan, Huang Chaozhu, Guo Xuyun, Zhu Ye, Thomas Tiju, Guo Haichuan, Attfield J Paul, Yang Minghui
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China.
Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
Angew Chem Int Ed Engl. 2021 Mar 15;60(12):6561-6566. doi: 10.1002/anie.202015856. Epub 2021 Feb 16.
Semiconducting metal oxides (SMOXs) are used widely for gas sensors. However, the effect of ambient humidity on the baseline and sensitivity of the chemiresistors is still a largely unsolved problem, reducing sensor accuracy and causing complications for sensor calibrations. Presented here is a general strategy to overcome water-sensitivity issues by coating SMOXs with a hydrophobic polymer separated by a metal-organic framework (MOF) layer that preserves the SMOX surface and serves a gas-selective function. Sensor devices using these nanoparticles display near-constant responses even when humidity is varied across a wide range [0-90 % relative humidity (RH)]. Furthermore, the sensor delivers notable performance below 20 % RH whereas other water-resistance strategies typically fail. Selectivity enhancement and humidity-independent sensitivity are concomitantly achieved using this approach. The reported tandem coating strategy is expected to be relevant for a wide range of SMOXs, leading to a new generation of gas sensors with excellent humidity-resistant performance.
半导体金属氧化物（SMOXs）被广泛用于气体传感器。然而，环境湿度对化学电阻器基线和灵敏度的影响仍是一个很大程度上未解决的问题，这降低了传感器的准确性，并给传感器校准带来了复杂性。本文提出了一种通用策略，通过用由金属有机框架（MOF）层隔开的疏水聚合物涂覆SMOXs来克服水敏性问题，该MOF层可保护SMOX表面并起到气体选择性功能。使用这些纳米颗粒的传感器装置即使在湿度在很宽范围内变化[0-90%相对湿度（RH）]时也显示出近乎恒定的响应。此外，该传感器在低于20%RH时具有显著性能，而其他防水策略通常会失效。使用这种方法可同时实现选择性增强和与湿度无关的灵敏度。所报道的串联涂层策略预计与广泛的SMOXs相关，从而产生具有优异耐湿性的新一代气体传感器。
