AI 中文总结
本文提出利用LED光热激发等离激元金纳米颗粒化学电阻器，动态调控气体吸附平衡，通过差分信号检测VOC并提升基线稳定性。
AI 中文摘要
准静态传感，即相对于事先在参考气体中观察到的基线信号，测量由分析物存在引起的传感器信号变化，是化学电阻传感中定性和定量分析物识别的现有技术水平。然而，这种方法容易受到基线漂移的影响，特别是对于廉价的微型化即时检测传感器，使用参考气体进行重复校准是不可行的。为了获取可靠的基线信息，需要在分析物和参考气体之间进行主动切换，这限制了微型化实现。传感器的动态激励提供了一种替代方案：通过外部刺激，传感器以受控方式可逆地偏离平衡，记录并解释依赖于存在的分析物的瞬态传感器响应。激励和响应信号的关联可以减少基线漂移的影响，此外，传感器响应中的动态特征可能包含有价值的信息。特别是光激活是一种强大且可能可微型化的方法，用于扰动吸附过程并因此诱导动力学。在这项工作中，我们报告了通过匹配等离激元共振的LED激发对混合型化学电阻金纳米颗粒复合材料进行光热加热，以动态移动分析物吸附平衡并以高度受控的方式诱导动态传感器响应。我们证明了这些传感器响应能够通过解释差分信号分量来检测挥发性有机化合物（VOC），并且该方法提高了化学电阻器的基线稳定性。
英文摘要
Quasi-static sensing, i.e., measurement of a sensor signal change induced by analyte presence with respect to a baseline signal observed in a reference gas beforehand, is the state of the art for qualitative and quantitative analyte identification in chemiresistive sensing. However, this approach is prone to baseline drift and, especially for inexpensive miniaturized point-of-care sensors, repeated calibration with reference gas is not feasible. To access reliable baseline information, active switching between analyte and reference gas would be required, causing a limitation for miniaturized implementation. Dynamic excitation of sensors offers an alternative: Via external stimuli the sensor is reversibly driven out of equilibrium in a controlled way, and the resulting transient sensor response, which is dependent on analytes present, is recorded and interpreted. Correlation of excitation and response signals can reduce effects of baseline drift and furthermore, dynamic features in sensor responses may contain valuable information. Especially light activation is a powerful and potentially miniaturizable approach to agitate sorption processes and therefore induce dynamics. In this work we report photothermal heating of hybrid, chemiresistive gold nanoparticle composites via LED excitation matching the plasmon resonance, to dynamically shift the analyte sorption equilibrium and induce dynamic sensor responses in a highly controlled way. We demonstrate that these sensor responses enable the detection of volatile organic compounds (VOC) via interpretation of differential signal components and that this approach improves the chemiresistors' baseline stability.
