Point Discharge Microplasma Optical Emission Spectrometer: Hollow Electrode for Efficient Volatile Hydride/Mercury Sample Introduction and 3D-Printing for Compact Instrumentation

Abstract

A miniaturized optical emission spectrometer was constructed with improved point discharge microplasma as an excitation source to enhance sample introduction efficiency and excitation efficiency. By using a hollow electrode as one of the discharge electrodes, analytecontaining chemical vapor yielded via hydride generation was transported and confined into the hollow electrode and subsequently guided into the microplasma with high sample introduction efficiency. Moreover, gaseous analyte species were directly diffused from inside the electrode into the center of the microplasma, instead of traditional external diffusion into the microplasma, resulting in sufficient participation in interactions and excitation in the plasma; thus, high excitation efficiency and stability can be achieved. A 3D-printing technique was used to fabricate some components for compact integration of this spectrometer. Physical characteristics of the microplasma, 3D-printing, and experimental parameters were all investigated to better understand the excitation capability and obtain optimal analytical performance. Under optimized conditions, As, Bi, Ge, Hg, Pb, Sb, Se, and Sn were successfully detected, with detection limits of 2.5, 0.44, 1.6, 0.10, 2.8, 1.5, 31, and 0.24 μg L −1 , respectively, and relative standard deviations all less than 4%. It was applied to the analysis of Certified Reference Materials (water, soil, and biological samples) and real water samples with satisfactory results. Because of its advantages of compactness, robustness, easy fabrication, and cost-effectiveness, it has a great prospect as a portable spectrometer for field analytical chemistry.

High-sensitivity and field analysis of lead by portable optical emission spectrometry using a microplasma trap

“…However, as typical excitation sources, ICP and MP are well known for large size and high energy consumption and are thereby incompetent for elemental field analysis. By contrast, microplasma excitation sources, such as dielectric barrier discharge (DBD), 8,9 point discharge (PD), 10,11 solution cathode/anode glow discharge (SCGD/SAGD), 12,13 and atmospheric pressure glow discharge (APGD), 14,15 are characterized by low cost, small size and low power consumption. Up to date, miniature OES instruments using various kinds of microplasma as excitation sources have frequently been developed, demonstrating great potential for field analysis of toxic elements in environmental water.…”

Three-Dimensional Printed Dual-Mode Chemical Vapor Generation Point Discharge Optical Emission Spectrometer for Field Speciation Analyses of Mercury and Inorganic Selenium

“…To the best of our knowledge, there are only a few applications of 3D printing in atomic spectrometry. 26 According to previous works, 27,28 nonhyphenated techniques based on chemical vapor generation were conducive to realize simple elemental speciation analysis via the selective determination of one species of the tested element. 29,30 The purpose of this work is to utilize the advantages of 3D printing, microplasma-OES, and chemical vapor generation to fabricate a miniaturized and compact dual-mode chemical vapor generation (CVG and PVG) point discharge (μPD) optical emission spectrometer for field elemental speciation analysis.…”

“…As a typical additive manufacturing technology, three-dimensional (3D) printing has driven innovation in the manufacturing industry and brought countless applications in a large variety of fields. , Compared to the traditional manufacturing techniques, 3D printing technologies provide a more unified and standardized platform for ordinary people to facilely and cost-effectively fabricate the parts of analytical devices, even some complex devices that cannot be fabricated by conventional techniques. − Importantly, the design files for the 3D printed devices can be shared online to make other laboratories produce analytical devices in a reproducible manner. To the best of our knowledge, there are only a few applications of 3D printing in atomic spectrometry …”

Reconsidering the Need for Empirical Alignment and Wavelength Calibration Steps in the Building of a Dispersive NIR Spectrometer with an Application for Ethanol Quantification Using a Polymer Filament 3D Printer

“…The use of polymer filament 3D printers to manufacture small-scale custom parts has become popular in recent years and has shown promising results in optical applications. , Several studies regarding polymer filament 3D printers associated with spectroscopy/optics are available in the literature. − However, the extent of how trustworthy these 3D-printed parts are according to the 3D project and printer limitations in the building of complete spectrometers is hardly brought up, also if fine adjustments or compensations in optics were made before the instrument or accessory use. Furthermore, some of these works apply 3D printing only as a complementary resource for building customized accessories to be coupled with commercial instruments and, even so, adjustments are made to the printed part …”