Iso-conversional kinetic analysis of quaternary glass re-crystallization

Abstract

Iso-conversional kinetic analysis is popular in scientific community for analyzing solid-state reactions (e.g., glass/amorphous and amorphous/crystal phase transformations, re-crystallization etc). It is a recognized significant tool to achieve useful outcomes for the solid state reaction under consideration. Present work is devoted to explore some insights of thermally activated crystallization using various heating rates (VHR) method. We have examined the correlation between iso-conversional activation energy and iso-conversional rate of crystal growth. In fact, we have observed the compensation law and iso-kinetic relationship using two different approaches for the study of crystallization phenomenon that drives thermally in an Arrhenian manner.Moreover, we found that the estimated intercepts and gradients (i.e., Meyer-Neldel energy and Meyer-Neldel pre-factor respectively) for both approaches also vary linearly and both sets are remarkably identical. These results approach to an inference for ensuring the equivalence of compensation law and iso-kinetic relationship and provide an understanding of various advanced materials in physical chemistry, materials sciences and solid-state physics.

Calorimetric studies of crystallization in Se76Te20Sn2Ge2 glass under heating/cooling mode

“…From the slope of these lines, one can calculate the activation energy (E i ) at the different extents of crystallization. This method of calculation of activation energy is referred to as VHR (Various Heating Rate) method as suggested by several research groups [37][38][39]. The Avrami exponent (order parameter) is determined at a specific temperature by the following equation as suggested by Boutarfaia et al 2002 andChristian 1971 [40, 41]:…”

“…By plotting a graph between lnK 0i versus E i , a straight line with a good correlation coefficient is obtained and with the help of its slope, we have calculated MN energy as shown in figure 7. Thus, figure 7 shows another interesting result which is the observation of the compensation effect [i.e., Meyer-Neldel rule (MNR)] for isoconversional crystallization [39]. In the present sample, the MNR is reflected as relations between (K 0i ) H and (E i ) H (i.e., direct Meyer-Neldel relation) and between (K 0i ) C and (E i ) C (i.e., inverse Meyer-Neldel relation).…”