The evaluation of selectivity/cross-sensitivity is one of the most important tests for gas sensor development, particularly that based on chemiresistive technology. It is known that chemiresistive gas sensors suffer from low selectivity when they provide sensitivity to several analytes. Typically, selectivity testing involves independently assessing a sensor’s response to a specific gas. However, there is a growing need to evaluate performance with interfering gases or gas mixtures since gas sensors are always exposed to gas mixtures in practice. Despite the great importance of selectivity characterization, currently, there are no standard methods of selectivity tests at conditions when target gas coexists with interfering gas compounds, which mimics real conditions. We outlined the four main methods researchers use to evaluate the cross-sensitivity of gas sensors. It highlights key aspects of selectivity test performance, assessment methodologies, and procedure features, attempting to classify them by their distinct characteristics. This review covers the essentials of gas properties, adsorption and desorption processes, and gas molecule interactions. Finally, we tried to address the lack of standardized protocols for evaluating chemiresistive gas sensors’ cross-sensitivity to interfering gases and guide researchers.

中文翻译：

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化学电阻气体传感器的交叉灵敏度：性质、方法和特性：系统评价


选择性/交叉灵敏度的评估是气体传感器开发中最重要的测试之一，尤其是基于化学电阻技术的传感器。众所周知，化学电阻气体传感器在对多种分析物敏感时选择性低。通常，选择性测试涉及独立评估传感器对特定气体的响应。然而，由于气体传感器在实践中总是暴露在气体混合物中，因此越来越需要评估干扰气体或气体混合物的性能。尽管选择性表征非常重要，但目前还没有在目标气体与干扰气体化合物共存的条件下进行选择性测试的标准方法，这模拟了真实条件。我们概述了研究人员用来评估气体传感器交叉灵敏度的四种主要方法。它强调了选择性测试性能、评估方法和程序特征的关键方面，并试图根据它们的不同特征对它们进行分类。这篇综述涵盖了气体特性、吸附和解吸过程以及气体分子相互作用的基本要素。最后，我们试图解决缺乏标准化协议来评估化学电阻气体传感器对干扰气体的交叉敏感性并指导研究人员的问题。