Array Point Discharge as Enhanced Tandem Excitation Source for Miniaturized Optical Emission Spectrometer

Abstract

A new compact tandem excitation source was designed and constructed by using an array point discharge (ArrPD) microplasma for a miniaturized optical emission spectrometer through coupling a hydride generation (HG) unit as a sample introduction device. Three pairs of point discharges were arranged in sequence in a narrow discharge chamber to construct the ArrPD microplasma, for improved excitation capability owing to the serial excitation. Besides, the discharge plasma region was greatly enlarged, therefore, more gaseous analytes could be intercepted to enter into the microplasma for sufficient excitation, for improved excitation efficiency and OES signal. To better understand the effectiveness of the proposed ArrPD source, a new instrument for simultaneous detection of atomic emission and absorption spectral responses was also proposed, designed, and constructed to reveal the excitation and enhancement process in the discharge chamber. Under the optimized conditions, the limits of detection (LODs) of As, Ge, Hg, Pb, Sb, Se, and Sn were 0.7, 0.4, 0.05, 0.7, 0.3, 2, and 0.08 μg L −1 , respectively, and the relative standard deviations (RSDs) were all less than 4%. Compared with a commonly used single point discharge microplasma source, the analytical sensitivities of these seven elements were improved by 3−6-fold. Certified Reference Materials (CRMs) were successfully analyzed with this miniaturized spectrometer, which features low power, compactness, portability, and high detectability, and is thereby a great prospect in the field of elemental analytical chemistry.

Atomic spectrometry update: review of advances in atomic spectrometry and related techniques

“…This was prepared using a gravimetric isotope mixture approach using two high-purity enriched Cu isotopes. The 63 Cu/ 65 Cu ratio determined for this mixture was 2.2423 ± 0.0009 (2SD) which was nearly identical to that of SRM976.…”

“…Na was found to be reduced by the electric preltering whereas the 40 Ar 23 Na + was removed by the reaction cell. Results indicated that precise 65 Cu/ 63 Cu ratios could be achieved with Na:Cu of 10, which was ten times higher than the level at which standard MC-ICP-MS analyses degrade.…”

Simultaneous determination of Cd, Pb, Cu and Zn as total and labile fractions in soil using a small-sized electrothermal vaporization capacitively coupled plasma microtorch optical emission spectrometer after diffusive gradients in thin-film passive accumulation

“…18–22 Since introducing a gaseous sample into a microplasma was found to be a relatively simple task, the microplasma technology was mainly developed as a specific high-sensitivity detector by optical emission spectrometry (OES) and mass spectrometry (MS) in gas chromatography (GC) or as a device for introducing derivatized species of elements generated under UV irradiation by plasma, known as plasma-induced vapor generation technology. 23–28 However, there are several limitations in the development of microplasma analytical technologies, the most important of which are the lack of stability and poor excitation capability in the case of samples with a complex matrix, because of the low operating power. 16 Thus, the discharge stability is disturbed in the case of direct introduction of liquid samples because of low tolerance for water-loaded aerosols.…”

Miniature Spectrometer Based on Gold Nanorod-Polyvinylpyrrolidone Film

“…Spectrometers, as one of the most important scientific instruments, are essential in biological detection, chemical analysis, and other fields. − However, traditional laboratory spectrometers are bulky, expensive, and fragile, which greatly limits their applications. In order to make spectroscopic instruments tiny and portable, miniature spectrometers with reduced size and power consumption have been extensively studied in recent years. , As summarized in Figure , miniature spectrometer techniques can be categorized into four types according to their working principles.…”