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

Materials Research Bulletin

Published On 2023/3/1

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.

Journal

Materials Research Bulletin

Published On

2023/3/1

Volume

159

Page

112107

Authors

Safa Kasap

Safa Kasap

University of Saskatchewan

Position

Professor of Electrical Engineering

H-Index(all)

49

H-Index(since 2020)

29

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

electronic materials

optoelectronic and photonic materials

devices

detectors

photoconductors

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Position

H-Index(all)

44

H-Index(since 2020)

19

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Odor sensor

Dosimeter

Thin films

University Profile Page

Go Okada

Go Okada

Kanazawa Institute of Technology

Position

H-Index(all)

33

H-Index(since 2020)

28

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0

I-10 Index(since 2020)

0

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0

Citation(since 2020)

0

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0

Research Interests

Optoelectronics

Dosimetry

X-ray Imaging

Phosphor

University Profile Page

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Safa Kasap

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2023/12/20

Article Details
Hidehito Nanto

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Materials Research Bulletin

The combined sol-gel and ascorbic acid reduction strategy enabling Ba2Co2Fe12O22 hexaferrite/graphene composite with enhanced microwave absorption ability

The inherent high conductivity and limited loss mechanism of graphene result in an impedance mismatch with free space impedance. Co2Y-type ferrite exhibits strong planar magnetic anisotropy and a high natural resonance frequency compared to other ferrites. Therefore, the utilization of Co2Y-type ferrite magnetic particles to impart magnetic loss capability to graphene is considered an effective strategy for enhancing electromagnetic wave absorption efficiency. Ferrite/RGO composite material with excellent microwave absorption properties was synthesized by coupling sol-gel derived Ba2Co2Fe12O22 hexaferrite with graphene oxide, followed by reduction using ascorbic acid. More noticeably, the ferrite particles stably adhere to the surface or interlayer of graphene through adsorption, while the reduced graphene oxide with residual oxygen-containing functional groups simultaneously enhances the dielectric …

Kokati Venkata Bhaskara Rao

Kokati Venkata Bhaskara Rao

VIT University

Materials Research Bulletin

Sensitizing effect of Yb3+ ions on 1.53 µm broadband and 548nm upconversion green emissions of Er3+-doped TeO2–WO3–GeO2 glasses

The Er3+-doped transparent glasses were the significant materials to design solid state visible lasers, near infrared lasers, upconverters, sensors and fiber amplifiers. The effect of Yb3+ sensitization on 1.53 µm broadband and 548 nm upconversion green emissions in TeO2–WO3–GeO2–ErF3–YbF3 (TWGErYb) glasses were studied. They were characterized through structural, optical absorption, near infrared and upconversion studies. The Judd-Ofelt theory was adopted to estimate several spectroscopic and radiative parameters. The laser characteristic parameters such as stimulated emission cross sections, gain band widths, figure of merit and quantum efficiencies were evaluated. Conveying the energy from Yb3+ to Er3+ ions and the reasons for non-radiative losses were highlighted. The quenching in luminescence of 1.53 µm broadband, the 548 nm upconversion green emissions and the enhanced decay …

A Srinivasan

A Srinivasan

Indian Institute of Technology Guwahati

Materials Research Bulletin

Highly ordered single domain Fe2-xCo1+ xGa (0≤ x≤ 1) nanoparticles synthesized by a template-less chemical route

A comprehensive study has been carried out on chemically synthesized Fe2-xCo1+xGa (0 ≤ x ≤ 1) nanoparticles using both experimental and theoretical tools. Adoption of a template-free preparation route ensured impurity-free and phase-pure Heusler alloy nanoparticles. Depending on the composition, these nanoparticles exhibit highly ordered L21 or X type Heusler alloy structure. These nanoparticles have high saturation magnetization (3.90 – 5.15 µB/f.u.), high Curie temperature (≥ 1100 K) and high effective anisotropy constant (∼ 106 erg/cc) along with low coercive field (≤ 12 Oe) and low remnant magnetization (≤ 0.03 µB/f.u.). Emergence of superparamagnetism in these single (magnetic) domain nanoparticles is another interesting aspect. The electronic density of states of these alloys near Fermi level have also been evaluated as a function of composition using ab initio calculations. These results …

Bin Tang

Bin Tang

Changzhou University

Materials Research Bulletin

A four-narrowband terahertz tunable absorber with perfect absorption and high sensitivity

Here, a simple four-band terahertz tunable narrowband absorber is proposed, which can achieve multimodal perfect absorption within 1–9 THz. We analyzed the physical mechanisms behind local surface plasmon resonance and impedance matching based on theoretical principles. By controlling the structural parameters, we use the eigen-mode and external field excitation to obtain the absorption peak and electromagnetic field distribution of the narrowband sensor under different structural parameters. Additionally, we studied the effect of the angle of incidence electromagnetic waves on the function of the absorber, found that the absorber has excellent characteristics in both low and high frequency states. We carry out a substance detection on four perfect absorption modes. The ambient refractive index sensitivity is 881.35 GHz/RIU, 439.65 GHz/RIU, 2664.46 GHz/RIU, 4501.19 GHz/RIU. The four-peak …

Mohammed Sultan Al-Buriahi

Mohammed Sultan Al-Buriahi

Sakarya Üniversitesi

Materials Research Bulletin

Design and tuneable magnetodielectric ferrite-based meta-absorbers for high-frequency microwave absorption applications

EM absorbers with outstanding absorption, shielding capability, and dissipation performance are still challenging in hostile environments. To address the EMI issues, the meta-absorbers of the spinel-based structure were designed and prepared. Herein, Zr-In co-substituted Ni-Zn nano ferrites with the composition of Ni 0.7 Zn 0.3 (ZrIn) x Fe 2–2x O 4 for 0≤ x≤ 0.20 with 0.05 step size were prepared using the citrate-gel self-ignition route. The characteristic features of the Zr-In doped NiZn nano ferrites were evaluated from FESEM, XRD, FTIR, and VSM, respectively. The bond lengths and unshared-shared edges in Zr-In doped NiZn ferrite were estimated using the Bertaut method. FTIR analysis confirms the occurrence of phase in Zr-In co-substituted Ni-Zn ferrite. The micrographs of Zr-In doped NiZn ferrite show circular and hexagonal mixed-shaped particles. SFD and high-frequency response from the Zr-In doped …

Sheng Zhu

Sheng Zhu

Eberhard Karls Universität Tübingen

Materials Research Bulletin

One-dimensional hierarchically structured strain sensor with high sensitivity, stretchability and durability for physiological monitoring

Developing strain sensors with metal film as sensing material is effective route in monitoring human physiological signals. However, most of them exhibit narrow stretchable range, poor detection limit and durability due to the rigidity and low ductility of metal. Here, a wrapping strategy is proposed to fabricate the strain sensor, which employs hydrogel layer to coat conductive Ni film on rubber band to form one-dimensional hierarchical structure. Impressively, the strain sensor achieves a low sensing strain of 0.005%, high stretchability of 352% and ultimate strength of 1870 kPa. Fast response time (0.32 s), high gauge factor (GF=33) and low electrical hysteresis are other characteristics of the sensor. It also presents excellent durability and frost-resistance, in which the electrical signals (ΔR/R0) still keep exceedingly steady after 10000 and 1000 cycles at 25°C and -30°C, respectively. As expect, it is sensitive in …

Debasish Das

Debasish Das

Indian Institute of Technology Kharagpur

Materials Research Bulletin

Electrophoretically Deposited Na3V2 (PO4) 3 and its Carbonaceous Composites as Promising Cathode for Sodium-ion Batteries

Sodium vanadium phosphate (NVP), a sodium ion super ionic conductor (NASICON), is one of the most attractive cathode materials for sodium ion batteries (SIBs). Electrophoretic deposition (EPD) is demonstrated to be an efficient synthesis tool to deposit strongly adhered and porous NVP carbonaceous material (viz. carbon nano tube (CNT) and reduced graphene oxide (rGO)) on aluminum current collector. EPD grown NVP delivers a stable reversible capacity ∼53.7 mAhg−1 at 0.1Ag−1 current density after 250 cycles. The introduction of CNT and rGO in the electrode significantly improves the electrochemical properties of NVP by providing better conduction pathways. Consequently, reversible capacities of 87 mAhg−1 and 70 mAhg−1 were obtained after 250 cycles at 0.1Ag−1 for NVP/RGO-CB and NVP/CNT-CB electrodes, respectively. These electrodes are able to deliver specific capacities of ∼70 mAhg−1 at …