Temporal evolution of tellurium emission lines in a capillary dielectric barrier discharge after hydride generation
Temporal evolution of tellurium emission lines in a capillary dielectric barrier discharge after hydride generation
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DOI：
10.1016/j.sab.2020.105936
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发表时间：
2020-09
期刊：
影响因子：
--
通讯作者：
S. Burhenn;J. Kratzer;J. Franzke
中科院分区：
文献类型：
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作者：
S. Burhenn;J. Kratzer;J. Franzke
在分析化学领域，介质阻挡放电(DBD)是一种广泛使用的痕量元素检测工具。由于在大多数DBD设备中等离子体具有良好的光学可达性，因此检测元素的一种方法是光发射光谱。此外，借助于时间分辨光学发射光谱，可以利用DBD的周期性来洞察等离子体发射的演化。作为分析物，碲通过氢化物发生被引入毛细管DBD。用与光谱仪相连的ICCD相机记录了放电的时间分辨宽带光谱。这使得能够同时跟踪沿放电周期的几个等离子体物种的发射。碲的最大发射信号明显滞后于放电气体氦的发射和氢背景的发射。通过记录的宽带谱表明，在放电周期中，两条被选择的碲线的比例发生了变化，这也导致了这两条线的信噪比不同。了解达到信号与背景比的最佳条件的时间点使得能够记录清楚的碲线光谱，而不需要额外的背景减去。
In the field of analytical chemistry, the dielectric barrier discharge (DBD) is a widely used tool for trace element detection. Due to the good optical accessibility of the plasma in most DBD devices, one way to detect elements is optical emission spectrometry. Moreover, by means of temporally resolved optical emission spectrometry, the periodicity of the DBD can be utilized in order to get insight into the evolution of the plasma emission. Serving as analyte, tellurium was introduced into a capillary DBD via hydride generation. Temporally resolved broad band spectra of the discharge were recorded with an ICCD-camera coupled to a spectrograph. This enables to simultaneously track the emission of several plasma species along the discharge cycle. The maximum emission signal from tellurium was significantly delayed to the emission of the discharge gas helium and the hydrogen background. By means of the recorded broad band spectra it was shown that the ratio of two selected tellurium lines changed during the discharge cycle, which also resulted in different signal to noise ratios for both lines. The knowledge of the point in time at which optimal conditions for the signal to background ratio was achieved enabled to record a clear spectrum of the tellurium lines without additional background subtraction.