Evaluation of trapping parameters in KCaSO4Cl: X (X=Ce, Dy, Mn or Pb) phosphor by TL

Abstract

Polycrystalline KCaSO4Cl: (Ce, Dy, Mn and Pb) phosphors prepared by solid state diffusion method have been studied for its trapping parameters by thermoluminescence (TL) phenomenon. The TL glow curves of KCaSO4Cl: (Ce, Dy, Mn and Pb) phosphor for different concentrations have been recorded at a heating rate of 2°Csec−1 and irradiated at a dose rate of 0.995kGyh−1 for 5Gy. The TL glow curves of γ-irradiated KCaSO4Cl: (Ce, Dy, Mn and Pb) phosphors show one glow peak indicating that only one set of traps is being activated within the particular temperature range each with its own value of activation energy (E) and frequency factor (s). The trapping parameters associated with the prominent glow peak of KCaSO4Cl: (Ce, Dy, Mn and Pb) is calculated by using Chen's half width method. The phosphors KCaSO4Cl: Ce, and Pb show first order kinetics while, Dy and Mn show the second order kinetics. The trap depth and frequency factors have been studied subsequently. The release of hole or electron from defect centers at the characteristic trap site initiates the luminescence process in this material.