  A-site deficient Ba$_{0.975}$La$_{0.017}$(ZrxTi$_{0.95-x}$)Sn$_{0.05}$O$_3$
(x = 0.05; 0.20) ceramics (BLaZ100xTS) were synthesized using the solid-state
reaction. The microstructural study revealed a high density and low porosity in
the studied ceramics. Besides, grain size lower than 1.5 micrometer was
observed in the studied compounds, which is due to the incorporation of the
rare earth element (lanthanum). X-ray diffraction and Raman studies revealed
that BLaZ5TS and BLaZ20TS crystallize in a perovskite-type structure with
tetragonal and cubic symmetry, respectively. The dielectric study showed a
normal ferroelectric-paraelectric phase transition for BLaZ5TS while a diffuse
phase transition is noticed for BLaZ20TS sample. The energy-storage density and
the associated energy efficiency were determined from the P-E loops versus
temperature and the calculated values are comparable with results obtained on
BCZT systems. Furthermore, the adiabatic temperature change (Delta)T was
calculated through the indirect method and a relatively high value of
(Delta)T/(Delta)E = 0.2 10-6 K m/V is obtained in BLaZ5TS system. The
simultaneous presence of energy storage property and electrocaloric
responsivity makes this system a promising environmentally friendly candidate
for application in electronic devices.
