Quantitative measurement of the nitrogen oxide mixture (NO_x, usually of NO and NO₂) usually relies on sophisticated, space-consuming, and expensive spectroscopy techniques such as gas chromatography (GC), Fourier-transform infrared spectroscopy (FTIR), and chemi-luminescence detection (CLD). The direct and portable measurement solutions are lacking in this regard. In this work, by utilizing the bimodular sensing strategy, we successfully demonstrated the differential measurement of NO_x with errors smaller than 8.3%, by correlating the sensor electrical and electrochemical responses. The effective detection is successfully displayed in the low-concentration ranges of 1–10 ppm for NO and 100 ppb–1 ppm for NO₂, where weak competitive gas co-adsorption mitigated the cross-sensitivities compared to the higher-concentration range. Based on the electron occupation with negligible competitive adsorption, the accurate theoretic prediction of the mixture responses versus component concentration relieves the reliance on repeated calibration and empirical functions. With the miniaturized size and simplified electrical feedthrough, the single bimodular nanorod sensor provides a promising solution for direct and portable NO_x analysis at low concentrations.

中文翻译：

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使用单个双模块 ZnO 纳米棒传感器进行低浓度 NOx 气体分析

氮氧化物混合物（NO _x，通常为 NO 和 NO ₂）的定量测量通常依赖于复杂、占用空间和昂贵的光谱技术，例如气相色谱 (GC)、傅里叶变换红外光谱 (FTIR) 和化学- 发光检测（CLD）。在这方面缺乏直接和便携的测量解决方案。在这项工作中，通过利用双模块传感策略，我们通过关联传感器电学和电化学响应，成功地展示了误差小于 8.3%的 NO _x的差分测量。在 NO 1–10 ppm 和 NO ₂ 100 ppb–1 ppm 的低浓度范围内成功显示有效检测，与较高浓度范围相比，较弱的竞争性气体共吸附减轻了交叉敏感性。基于具有可忽略竞争吸附的电子占据，混合物响应与组分浓度的准确理论预测减轻了对重复校准和经验函数的依赖。随着小型化的尺寸和简化电馈通，所述单个纳米棒双模块传感器提供直接和便携式NO一个有前途的解决方案_X在低浓度的分析。