A multi-quartz-enhanced photothermal spectroscopy (M-QEPTS) based trace gas detection method is reported for the first time. Different from traditional QEPTS sensor employing a single quartz tuning fork (QTF) as a photothermal detector, two QTFs were used in M-QEPTS to increase the signal amplitude by adding the generated piezoelectric signals. The coating film of the QTFs was removed in order to improve the laser absorption and transmission. Acetylene (C₂H₂) was chosen as the target analyte. Wavelength modulation spectroscopy (WMS) and 2nd harmonic detection were utilized for the concentration detection. Limit of detection (LoD) of 0.97 ppm was achieved with a 1 second integration time for the M-QEPTS sensor, which realized a 1.51 times signal enhancement compared to a traditional QEPTS sensor employing a single QTF. By using an Allan deviation analysis approach, LoD of 0.19 ppm for an optimum integration time of 200 s was obtained.

首次报道了基于多石英增强光热光谱（M-QEPTS）的痕量气体检测方法。与采用单个石英音叉（QTF）作为光热探测器的传统QEPTS传感器不同，M-QEPTS使用两个QTF，通过添加生成的压电信号来增加信号幅度。去除QTF的涂层膜以改善激光吸收和传输。选择乙炔(C ₂ H ₂ )作为目标分析物。波长调制光谱（WMS）和二次谐波检测用于浓度检测。 M-QEPTS 传感器的积分时间为 1 秒，检测限 (LoD) 为 0.97 ppm，与采用单个 QTF 的传统 QEPTS 传感器相比，信号增强了 1.51 倍。通过使用艾伦偏差分析方法，获得了 0.19 ppm 的 LoD，最佳积分时间为 200 秒。