Mechanoluminescence of Ca2MgSi2O7: Eu2+, Dy3+ Phosphor by Impulsive Deformation

Abstract

Di-calcium magnesium silicate phosphor doped with Eu2+ and Dy3+ was prepared using solid state reaction technique under a reducing atmosphere. Prepared sample suffered an impulsive deformation with an impact of a piston for mechanoluminescence (ML) investigations. A temporal characteristic of ML of the phosphor was observed, which expressed single sharp peak with a long decaying section. In order to investigate about the luminescence centre responsible for ML peak, ML spectrum of the same phosphor was also observed. ML spectrum recorded shown similarity in shape as well as peak wavelength with Photoluminescence (PL) spectrum that verifies the existence of single emission centre due to the transition of Eu2+ ions i.e. transitions from any of the sublevels of 4f65d1 configuration to 8S7/2 level of the 4f7 configuration. Decay rates for different impact velocities were also calculated using curve fitting technique. Time of ML peak and rate of decay did not change largely with respect to increasing impact velocity of the load and peak ML intensity varied linearly. Increasing impact velocity causes more number of Eu2+ ions to get excited to the higher energy level, subsequently de-excitation of more Eu2+ ions occurs. This gives rise to increase in ML intensity.