Enhanced Thermal Energy Harvesting Using Li, K-Doped Bi0.5Na0.5TiO3 Lead-Free Ferroelectric Ceramics

This study deals with the investigation of lead-free ferroelectric materials for potential thermal energy harvesting applications. Lead-free ferroelectric ceramics offer nonpolluting alternatives to their lead-based counterparts. However, their applications are limited because of their comparatively low performance. In this study, an attempt has been made to shed some light on the thermal energy harvesting potential of these materials through the use of Olsen cycle. Two compositions of Bi0.5Na0.5TiO3 (BNT), Bi0.5Na0.44K0.06TiO3 (BNKT), and Bi0.5Na0.425Li0.075TiO3 (BNLT), were explored. It was observed that maximum energy densities of 1986 JL(-1) per cycle (0.1-5.2 MVm(-1); 25-120 degrees C) and 1146 JL(-1) per cycle (0.1-11.2 MVm(-1); 25-110 degrees C) were obtained for BNKT and BNLT samples, respectively. The reported energy density is higher than that of most lead-based compounds. The results motivate the possible use of lead-free materials for thermal energy harvesting applications.