TSL/OSL/RPL Automated and Integrated Measurement System (TORAIMS).

Sensors & Materials

Published On 2021/7/15

Thermally stimulated luminescence (TSL), optically stimulated luminescence (OSL), and radio-photoluminescence (RPL) are radiation-induced luminescence phenomena, and they are widely used for radiation dosimetry today. Despite their successful applications, the R&D of conventional and new phosphor materials is still actively performed in a wide range of research fields from basic science to application. Although these phenomena are considered to be different, they share common physical processes such as the generation, trapping, and transfer of electronic charges. In order to have a deeper look into these phenomena, it is important to comprehensively characterize those of a single material. For this, we have constructed a prototype TSL/OSL/RPL automated and integrated measurement system (TORAIMS), and then the system performance has been studied. The system offers automated and integrated …

Journal

Sensors & Materials

Published On

2021/7/15

Volume

33

Authors

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

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44

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19

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0

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0

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0

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Odor sensor

Dosimeter

Thin films

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Other Articles from authors

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Journal of Alloys and Compounds

Radiophotoluminescence properties of Bi-doped NaCaBO3

Bi-doped NaCaBO3 exhibits radiophotoluminescence (RPL) properties, where the Bi2+ centre is formed through X-ray irradiation. As a result of RPL, a broad emission band appears around 800 nm in the photoluminescence (PL) spectrum, attributed to X-ray irradiation. The intensity of the PL signal is proportional to the irradiation dose, making it useful for measuring accumulated radiation dose. The sensitivity depends on the doping concentration of Bi, and the optimal concentration to maximize sensitivity is approximately 0.005%. With a laboratory-constructed reader system, the optimal sample enables measurement of X-ray dose as low as 25 mGy. Following irradiation, the Bi2+ signal slightly increases by about 13%, but it is significantly reduced to around 7% of the initial value after heat treatment at 500°C for 100 s. The formation and annihilation of the Bi2+ centre can be reproduced multiple times. Therefore …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Sensors and Materials

Radio-photoluminescence Properties of Eu-doped CaBPO5

Eu-doped CaBPO5 was synthesized by the solid-state reaction route, and then its radiophotoluminescence properties were studied. On the basis of steady-state and time-resolved photoluminescence (PL) studies, it was confirmed that Eu2+ is formed by X-ray irradiation due to the valence change of the Eu ion (Eu3+→ Eu2+). In addition, for dosimetric applications, it was demonstrated that the PL intensity of Eu2+ is proportional to the accumulated radiation dose, is stable after irradiation, and can be reversed by heat treatment at 500℃ for 100 s.

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Japanese Journal of Applied Physics

Radiophotoluminescence properties of Eu-doped Li2SrSiO4 for radiation detectors

To search for new radiophotoluminescence (RPL) materials, Eu-doped Li 2 SrSiO 4 was synthesized by the solid-state reaction and then studied its RPL properties for radiation detector applications. All the samples were identified to be Li 2 SrSiO 4 by X-ray diffraction. The as-prepared sample shows photoluminescence (PL) due to Eu 3+ while an additional PL band appears due to a formation of Eu 2+ after X-ray irradiation. This indicates that the Eu-doped Li 2 SrSiO 4 has RPL properties. The sensitivity of RPL (or PL intensity of Eu 2+) to X-ray dose is the highest when the Eu concentration is 0.1%, and the dynamic range is 5–10 000 mGy. In addition, the generated Eu 2+ is so stable that only 5% of the signal degrades over 20 min after irradiation. The RPL signal notably decreases to about 30% of the initial value by heating at 500 C for 100 s, and it is reproducible multiple times even after the heat treatment.

2023/12/20

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Journal of Materials Science: Materials in Electronics

ESR studies to elucidate the origin of the RPL emission of undoped-CaSO4

Recent research has shown that CaSO4, without any intentional addition of impurities, exhibits remarkable radiophotoluminescence (RPL) properties. However, the origin of the RPL in CaSO4 has yet to be fully understood. ESR measurements were carried out to identify the defect species responsible for RPL and elucidate the luminescence’s origin. ESR measurements on undoped-CaSO4 with different radiation sensitivities showed SO4−, SO2−+SO3−, PO42−, Si=O3 in P2O5–SiO2 (E’ center), Al2O3 hole center and Mn2+ defect species in CaSO4. This means that CaSO4 contains Al2O3, Mn2+, P, and Si as impurities, which are not intentionally added to CaSO4. As the results of this study, the different impurity states may influence the radiation sensitivity of the materials. It is suggested that the deliberate addition of P and Si elements, Al2O3 and Mn2+ could control the RPL properties.

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Materials Research Bulletin

X-ray induced reduction of Sm3+ into Sm2+ in Li2CaSiO4 and its potential for radiation measurement applications

In Sm3+-doped Li2CaSiO4, the Sm3+ ion is reduced to the Sm2+ state by X-ray irradiation. The valence change was confirmed by the difference in their photoluminescence spectra, measured before and after irradiation. Only luminescence peaks due to the 4f-4f transitions of Sm3+ are observed before the irradiation while an additional luminescence band is observed at 900 nm due to the 5d-4f transition of Sm2+. The reaction is that a fraction of X-ray generated electrons is captured by Sm3+ ions, which convert to the Sm2+ state. The generated Sm2+ state is fairly stable while it is effectively reversed back to the Sm3+ state by a heat treatment at an elevated temperature. A numerical approximation revealed the activation energy to be 0.40 and 0.52 eV. Even after the heat-treatment, the reduction of Sm3+ to Sm2+ is reproducible multiple times, which shows good potential for using radiation measurement applications.

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Journal of Materials Science: Materials in Electronics

Radio-photoluminescence properties of Eu-doped SrAl2O4 ceramics and thermally assisted charge transfer process

Radio-photoluminescence (RPL) properties of Eu-doped SrAl2O4 are studied focusing on the generation of a luminescent center by ionizing radiation of X-ray and its extinction by a thermally assisted charge transfer. The single phases of SrAl2O4 doped with Eu at concentrations of 0.05–1.0% are synthesized via solid-state reactions, as confirmed by X-ray diffractions analyses. They show photoluminescence (PL) due to both Eu3+ and Eu2+, and the PL intensity due to Eu3+ decreases after X-ray irradiation while the one due to Eu2+ notably increases. This indicates that Eu2+ as a luminescence center is generated as RPL through reduction from Eu3+ to Eu2+ by ionizing radiation of X-ray. Particularly, the 0.1% Eu-doped sample shows the highest sensitivity to X-ray dose, and the lowest detection limit is estimated to be 0.3 Gy with the present reader system. The RPL signal is reasonably stable, and it depends on …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Recent advances in radiophotoluminescence materials for luminescence dosimetry

Radiophotoluminescence (RPL) is a phenomenon in which a luminescence centre is formed in a medium upon interaction with ionizing radiation. The RPL is observed by a conventional photoluminescence (PL) technique, and the PL intensity is proportional to the dose. With the latter feature, the RPL has found successful applications in personnel and environmental dosimetry. However, the conventional materials considered for radiation measurements may be limited to Ag-doped phosphate glass, LiF, and Al 2 O 3: C, Mg. The recent research works, however, have found a number of additional RPL materials for luminescence dosimetry. The aim of the present paper is to review the series of newly reported RPL materials and potential applications in dosimetry.

2022/11/22

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Optically stimulated luminescence dosimeters: principles, phosphors and applications

This review paper discusses the basics of the optically stimulated luminescence (OSL) phenomenon, phosphors for OSL, functional design of OSL phosphors, and application areas of the OSL phenomenon, such as radiation dose monitoring for individual and environmental, computed radiography for medical and dental diagnosis, dating, security, archaeological dating, and autoradiography for drug discovery. Finally, the future prospects of the OSL phenomenon as passive-type dosimeters are mentioned.

2022/11/21

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

IEEJ Transactions on Sensors and Micromachines

Proposal of Temperature Behavior Analysis and Temperature Dependence Reduction of Stem Water Content Variation Sensor

Proposal of Temperature Behavior Analysis and Temperature Dependence Reduction of Stem Water Content Variation Sensor - NASA/ADS Now on home page ads icon ads Enable full ADS view NASA/ADS Proposal of Temperature Behavior Analysis and Temperature Dependence Reduction of Stem Water Content Variation Sensor Ueno, Chiemi ; Hirasawa, Kazuki ; Takei, Yoshinori ; Nanto, Hidehito Abstract Publication: IEEJ Transactions on Sensors and Micromachines Pub Date: June 2022 DOI: 10.1541/ieejsmas.142.117 Bibcode: 2022IJTSM.142..117U No Sources Found © The SAO/NASA Astrophysics Data System adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86A NASA logo Smithsonian logo Resources About ADS ADS Help What's New Careers@ADS Social @adsabs ADS Blog Project Switch to full ADS Is …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Sensors and Materials

Radiophotoluminescence Imaging Reader for Passive Dosimetry

In this study, we constructed an image reader system for two-dimensional radiation dosimetry based on radiophotoluminescence (RPL). The reader system mainly consists of a Peltier-cooled CMOS camera and an LED excitation source, as well as control units, and it offers an arbitrary excitation wavelength (eg, 365, 405, 460, 530, and 630 nm) and a wide spectral detection range (200–1000 nm) to be used for a wide range of prototype image detectors having different spectral features. Using the developed system, we were able to successfully obtain X-ray projection images recorded on a commercial RPL detector [Ag-doped phosphate glass (Ag-PG) plate] as well as custom-made prototypes of flexible imaging plates (IPs). Furthermore, the reader system is applicable not only for RPL imaging but also for conventional optically stimulated luminescence (OSL) imaging, which was demonstrated by using a …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Japanese Journal of Applied Physics

RPL properties of samarium-doped CaSO4

Radiophotoluminescence (RPL) properties of Sm-doped CaSO 4 for radiation dosimetry applications are reported. The samples with varying Sm concentrations are prepared via the solid-state reaction process. The as-prepared samples show photoluminescence due to typical 4f–f transitions of Sm 3+ whereas, after X-ray irradiation, additional emission features appear with a broad band peaking at 630 nm as well as a set of multiple sharp lines across 680–820 nm, which are attributed to the 5d–4f and 4f–4f transitions of Sm 2+, respectively. Therefore, the RPL in the present material system relies on the generation of Sm 2+ centers. The sensitivity is about 3 times lower than that of Ag-doped phosphate glass, but no fading and build-up of signal are evident even immediately after the irradiation. The signal is reversible by heat-treatment at 500 C, and is reproducible even after the thermal erasure, especially when …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Phosphors for Radiation Detectors

radiophotoluminescence (RPL)

This chapter covers a wide range of radio‐photoluminescence (RPL) technologies, from fundamentals to applications. It presents the definition of the term of RPL and distinguishes it from thermally‐stimulated luminescence and optically‐stimulated luminescence as a different type of dosimetric technique using a phosphor medium. RPL is a very powerful tool when the measurement environment requires exposure to light or heat. The chapter introduces a list of RPL materials and their fundamental properties, as reported in the literature. The RPL center is typically very stable and the resulting luminescence is due to electronic transitions within the RPL center. The chapter also introduces the principal properties as well as applications of four selected RPL materials with many illustrative materials. These include: Ag‐doped sodium‐aluminophosphate glasses, Al …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Phosphors for Radiation Detectors

Optically‐Stimulated Luminescent Dosimeters

The luminescence phenomenon due to the thermal stimulation is called thermally‐stimulated luminescence (TSL), while the one due to the optical stimulation is called optically‐stimulated luminescence (OSL). This chapter focuses on the principles and applications of OSL, which are utilized today in personnel dose monitoring, environmental dose monitoring, and geographical dating. OSL phenomenon has been used in personnel dose monitoring and imaging plates for computed radiography since the 1980s. A dosimeter using C‐doped Al 2 O 3 (Al 2 O 3 :C) developed by Landauer, Inc. is one of those passive‐type dosimeters using OSL phenomenon for personnel dose monitoring applications. Al 2 O 3 :C …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Journal of The Institute of Electrical Engineers of Japan

What Did the Great Persons Who Changed the World Think and Say?

What Did the Great Persons Who Changed the World Think and Say? - NASA/ADS Now on home page ads icon ads Enable full ADS view NASA/ADS What Did the Great Persons Who Changed the World Think and Say? Nanto, Hidehito Abstract Publication: Journal of The Institute of Electrical Engineers of Japan Pub Date: January 2022 DOI: 10.1541/ieejjournal.142.34 Bibcode: 2022JIEEJ.142...34N full text sources Publisher | © The SAO/NASA Astrophysics Data System adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86A NASA logo Smithsonian logo Resources About ADS ADS Help What's New Careers@ADS Social @adsabs ADS Blog Project Switch to full ADS Is ADS down? (or is it just me...) Smithsonian Institution Smithsonian Privacy Notice Smithsonian Terms of Use Smithsonian Astrophysical Observatory …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Materials Letters

Radiation-induced reduction of Eu3+ doped in SrAl2O4

In this letter, we report radio-photoluminescence (RPL) properties of Eu-doped SrAl2O4. The RPL is a phenomenon in which a new luminescence center is generated by ionizing radiation. The material was synthesized via the solid-state reaction. The synthesized sample shows photoluminescence (PL) due to the 4f-4f transition of Eu3+ and the 4f65d1 → 4f7 transition of Eu2+. After X-ray irradiation, the former emission intensity decreases while the latter one increases, and the extent of the change depends on the radiation dose. The change in the RPL is attributed to a reduction of Eu3+ by trapping an X-ray generated electron (Eu3+→Eu2+). In addition, a heat-treatment effectively reverses the above reaction by detrapping an electron from the Eu2+ center.

2021/11/15

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Sensors & Materials

TSL/OSL/RPL Automated and Integrated Measurement System (TORAIMS).

Thermally stimulated luminescence (TSL), optically stimulated luminescence (OSL), and radio-photoluminescence (RPL) are radiation-induced luminescence phenomena, and they are widely used for radiation dosimetry today. Despite their successful applications, the R&D of conventional and new phosphor materials is still actively performed in a wide range of research fields from basic science to application. Although these phenomena are considered to be different, they share common physical processes such as the generation, trapping, and transfer of electronic charges. In order to have a deeper look into these phenomena, it is important to comprehensively characterize those of a single material. For this, we have constructed a prototype TSL/OSL/RPL automated and integrated measurement system (TORAIMS), and then the system performance has been studied. The system offers automated and integrated …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Radioprotection

Characterization of optically-stimulated luminescence properties by NaCl: Eu2+ crystal and the thermal response

[en] Landauer optically stimulated luminescence (OSL) technology nanoDot dosimeters (OSLDs) are characterized for use in mammography screening at various tube voltages, mAs values and target/filter combinations. The average glandular dose (AGD) for a 50-mm breast, based on the representative compressed breast thickness of a 45-mm polymethyl methacrylate (PMMA) phantom, is assessed using OSLDs with different beam conditions. Further, the linearity of the OSLD response is measured and angular dependence tests are performed for various tube potentials, mAs and target/filter combinations. The breast-absorbed doses are measured at various depths for a 32-kVp X-ray beam at 100 mAs, with a Mo/Rh target/filter combination. The measured incident air kerma values at different lateral positions exhibit a maximum deviation of 6%, and the average relative response of the OSLDs at the reference point (center) with respect to various lateral positions is found to be 1.001±0.09%. The calculated AGD values are in the 1.3±0.1-3.5±0.2 mGy range, depending on the tube potential, tube loading and target/filter combinations. An exposure setup featuring the auto-exposure control (AEC) mode, 28 kVp, 73.8 mAs, and a Mo/Rh target/filter combination may be preferred for mammography screening for a compressed breast thickness of 45 mm.(authors)

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

電気学会研究会資料

Transient response analysis and feature extraction of semiconductor gas sensors for an application to machine olfaction

瀬戸就一 他: 半導体式ガスセンサの過渡応答出力の解析, 電気学会論文誌 E センサマイクロマシン準部門誌 Vol. 125 No. 3, p. 129-134 (2005)

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Radiation Measurements

Physical and dosimetric characteristics of radiophotoluminescent glass from two-photon excitation microscopy

We investigate the physical and dosimetric characteristics of Ag-activated phosphate glass exposed to proton beams with various energies. We present time-resolved blue and orange radiophotoluminescent (RPL) spectra and examine the dependence of the peak wavelengths and RPL area intensities on gate time. Moreover, we consider various micro-scale 3D patterns written on Ag-activated glass by a focused proton beam and evaluate their orange and blue RPL axial-profiles using two-photon excitation microscopy. Finally, we discuss the remarkable broadening of the Bragg curve observed in Ag-activated glass and argue that it should be attributed to the saturation effect and/or non-linearity effect from the viewpoint of the relation between the dose delivered and the signal.

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University of California, San Diego

Sensors & Materials

Design of Multi-module LED Headlamp of Vehicle Under Federal Motor Vehicle Safety Standard.

A light-emitting diode (LED) low-beam headlamp system was designed following the automotive headlamp regulations in Federal Motor Vehicle Safety Standard 108 (FMVSS 108). To design the system, we used the optical simulation software Light Tools. Using the focusing properties of an ellipsoidal reflector and an asymmetric light source floorboard, we enabled the light projected through the lens to form the cutoff lines that are required in regulations. The newly designed LED low-beam headlamp system can replace the shade component in conventional projector-type headlamp systems, reducing energy loss and effectively increasing light utilization efficiency. Using the concept of light pattern superposition, we superposed the light patterns of multiple modules to reduce the number of LED lights used and achieve satisfactory utilization efficiency. We used the simultaneous multiple-surface (SMS) design method …

Chika Takai-Yamashita

Chika Takai-Yamashita

Gifu University

Sensors & Materials

Highly Sensitive Amperometric Hydrazine Sensor Developed from Gold Nanoparticles Electrodeposited on Glassy Carbon Electrode Modified with Graphene Oxide and Poly (3, 4 …

In recent years, the approach of metal electrodeposition on the electrode surface to fabricate a highly sensitive electrochemical sensor has been extensively investigated with the purpose of detecting electroactive molecules or species.(1–4) To develop highly sensitive electrochemical sensors, gold nanoparticles (AuNPs) are one of the widely used electrode modifiers owing to their attractive characteristics such as good biocompatibility, increased electrocatalytic activity, and chemical stability, as well as they provide an enhanced specific surface area.(5–7) In addition, AuNPs can be readily functionalized with various nanomaterials to be developed as gold-based nanocomposites for electrochemical sensors such as AuNPs–carbon nanomaterials,(8) AuNPs–metal oxide,(9) AuNPs–metal dichalcogenide,(10) AuNPs–metal organic framework,(11) AuNPs–imprinted polymer,(12, 13) and AuNPs–polymer-metal oxide …

2023/12/15

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Hikaru Aono

Hikaru Aono

Shinshu University

Sensors & Materials

Experimental Analyses of Aerodynamic Force Generation and Wing Motion Associated with a Single-motor-driven Butterfly-inspired Flapping-wing Robot.

The fascinating flight traits of butterflies, such as low wing loading, low flapping frequency, and the ability for long-distance flight, have intrigued scientists and engineers. To study these mechanisms, a 2.7 g butterfly-inspired flapping-wing micro air vehicle (FWMAV) was developed using a combination of a single motor, elastic bands, a driving shaft, shape optimization, and a butterfly-like wing planform. During tethered experiments, aerodynamic forces and wing motions were simultaneously measured to understand the aerodynamics of the butterfly-inspired FWMAV. The results show that the ranges of resultant flapping and lead-lag motion of the wing of the robot were within those of real butterflies during the first stroke. The lift varied with the flapping motion and was sufficient for flight but averaged to zero over one flapping cycle because the opposite direction of lift was generated during the upstroke. These findings …

Dr. Mohd Shihabuddin Ahmad Noorden

Dr. Mohd Shihabuddin Ahmad Noorden

Universiti Teknologi MARA

Sensors & Materials

Clinical Performance of Reverse Transcription Loop-mediated Isothermal Amplification COVID-19 Assay on Gold-nanoparticle-modified Screen-printed Carbon Electrode Using …

In late December 2019, the world was shocked by the emergence of a novel coronavirus (CoV) that causes coronavirus disease (known as COVID-19). In an effort to curb the spread of the virus, the US Food Drug and Administration (FDA) issued the Emergency Use Authorization (EUA) to authorize unapproved drugs and medical devices, including the implementation of real-time RT-PCR, which is a diagnostic laboratory tool recommended by WHO and considered the gold standard for COVID-19 detection.(1, 2) It requires a series of procedures involving the amplification of nucleic acids, including reverse transcription, denaturation, primer annealing, and extension.(3, 4) However, real-time RT-PCR can only be carried out in certified laboratories with expensive equipment maintenance and trained personnel, and with a turnaround time (TAT) of more than 24 h.(3) In our context, TAT is the time taken from sample …

2023/10/20

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Akifumi Sugiyama

Akifumi Sugiyama

Kyoto University

Sensors & Materials

Development of Observation Method for Isoflavones Secreted by Soybean Roots in Rhizobox Using Sheets with Immobilized Bovine Serum Albumin.

A sensing method was developed to qualitatively evaluate the distribution of soybean isoflavones secreted by roots of soybeans transplanted into a simplified rhizobox by transferring them onto pieces of glass microfiber filter (sheets) with immobilized bovine serum albumin (BSA). To take advantage of fluorescence quenching by the interaction between BSA and soybean isoflavones, BSA was chemically bonded onto the sheets. The sheets with immobilized BSA were brought into contact with a nylon mesh (1 µm mesh aperture) of a simplified rhizobox, and secretions from soybean roots were transferred to the sheets. Fluorescence images before and after contact were captured with an electron-multiplying CCD camera to visualize and analyze fluorescence quenching. The results indicated that soybean isoflavone was spread within 2 to 3 mm from the roots.

2023/11/30

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Wan Jefrey Basirun

Wan Jefrey Basirun

Universiti Malaya

Sensors & Materials

Sensitive and Selective Electrochemical Sensor for Antimony Using Boron-doped Diamond Nanoparticles.

In this study, boron-doped diamond nanoparticles modified on the surface of a screen-printed electrode (SPE) were prepared for the sensitive and selective determination of Sb3+ using square wave voltammetry. The effect of electrochemical parameters such as the type of supporting electrolyte, pH, signal per background, and scan rate on the sensitivity of the sensor for the detection of Sb3+ was investigated. Under optimized conditions with an amplitude of 0.05 V, a frequency of 50 Hz, and an E-step of 0.05 V, the square wave voltammogram between− 1.0 and 1.0 V gave a limit of detection of 2.41× 10− 8 M for an Sb3+ concentration range from 0.19 to 0.59 μM. The method was used to determine Sb3+ ions in river water with satisfactory results. The modified electrode displayed benefits such as high sensitivity and selectivity, long-term stability, easy preparation, and wide linear range.

2023/12/15

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