Jafar M. Parakkandy

Giant energy harvesting potential in (100)-oriented 0.68PbMg1/3Nb2/3O3–0.32PbTiO3 with Pb(Zr0.3Ti0.7)O3/PbOx buffer layer and (001)-oriented 0.67PbMg1/3Nb2/3O3–0.33PbTiO3 thin films

This work emphasis on the competence of (100)-oriented PMN–PT buffer layered (0.68PbMg1/3Nb2/3O3–0.32PbTiO3 with Pb(Zr0.3Ti0.7)O3/PbOx buffer layer) and (001)-oriented PMN–PT (0.67PbMg1/3Nb2/3O3–0.33PbTiO3) for low grade thermal energy harvesting using Olsen cycle. Our analysis (based on well-reported experiments in literature) reveals that these films show colossal energy harnessing possibility. Both the films are found to have maximum harnessable energy densities (PMN–PT buffer layered: 8 MJ/m3; PMN–PT: 6.5 MJ/m3) in identical ambient conditions of 30–150°C and 0–600 kV/cm. This energy harnessing plausibility is found to be nearly five times higher than the previously reported values to date.

Application Oriented Selection of Optimal Sintering Temperature from User Perspective: A Study on K0.5Na0.5NbO3 Ceramics

This work presents a novel user oriented approach that can relate materials science with technological applications in a more transparent, systematic and efficient manner. We have made an attempt to figure out the optimal (corresponding to best combination of material properties) sintering temperature of K0.5Na0.5NbO3 (KNN) for transducer and electrical energy storage applications. The weights and priority of vital physical properties for applications understudy are calculated using the quality function deployment (QFD) method. Losses (tanδ), charge storage properties (ϵr, Pr and EC) and elastic compliance (sE12 and sE11) are found to have negative priority for transducer application while in the other case d31, tanδ, sE12 and sE11 are spotted to have negative priority. Priority order for transducer and energy storage application is d31>kp>QM>Tc>tanδ>ϵr>Pr=EC=sE12=sE11>ρ and ϵr>d31=tanδ>sE12=sE11>Tc>Pr>EC>kp>ρ>QM, respectively. Finally, 1080°C (transducer) and 1120°C (capacitor) are the found to be the most appropriate solutions among the alternatives under using modified analytic hierarchy process (AHP).