Precision radiation measurement: LiZnBO₃:Ce phosphor thermoluminescent properties

Area of Science:

• Solid-state physics
• Materials science
• Radiation detection

Background:

• Thermoluminescence (TL) dosimetry is crucial for radiation monitoring.
• Developing sensitive and stable TL materials is an ongoing research area.
• Lithium zinc borate (LZB) is a potential host material for TL dosimeters.

Purpose of the Study:

• To evaluate the thermoluminescence dosimetry potential of Ce-doped lithium zinc borate (LZB).
• To investigate the effect of Ce-doping on the structural, magnetic, and dosimetric properties of LZB.
• To assess the linearity, sensitivity, thermal stability, and fading characteristics of LZB:Ce.

Main Methods:

• Solid-state reaction method for synthesis.
• X-ray Diffraction (XRD) and Fourier-Transform Infrared Spectroscopy (FTIR) for structural analysis.
• Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDS) for elemental analysis.
• Vibrating Sample Magnetometer (VSM) for magnetic characterization.
• Irradiation with 6 MeV electron and 6 MV X-ray beams from a clinical LINAC.
• Thermoluminescence glow curve analysis using Chen's peak-shape method and Computerized Glow Curve Deconvolution (CGCD).

Main Results:

• Ce-doping (1%) in LZB enhanced dose-response linearity and sensitivity compared to undoped LZB.
• Superparamagnetic behavior emerged in LZB:Ce after doping.
• Kinetic analysis confirmed general-order kinetics and significant charge carrier re-trapping.
• Activation energies for shallow and deep traps were determined.
• LZB:Ce exhibited superior thermal stability and improved fading over 50 days.

Conclusions:

• Ce-doped LZB is a robust and technically viable candidate for thermoluminescence dosimetry.
• The material demonstrates improved dosimetric properties, including enhanced linearity, sensitivity, thermal stability, and reduced fading.
• Further long-term studies are recommended to fully assess its feasibility as an alternative dosimetry material.