Enhancement of the electrocaloric effect in PbZr0.7Ti0.3O3 ceramics via La doping: Driven by phase co-existence or defect effects?

Lattice defects and their effects have been pivotal in studies of phase transitions a wide range materials. Introduction such into ferroelectric material through doping secondary elements can be tailored towards specific applications but the mechanism which bulk properties change is seldom scrutinized. Here we study effect systematic La substitution PbZr0.7Ti0.3O3 (PZT 70/30) ceramics whereby analyzed temperature dependent estimated changes that could induced upon application an external electric field, namely electrocaloric (ECE). Expecting entropic to maximal under applied suitability doped PZT 70/30 system for EC had motivation undertake current task as this composition reportedly host rich variety phases depending on content including relaxor antiferroelectric (AFE) states. An (EC) 1.15 °C temperatures 8% at 45 kV/cm field was from experimental data, possible origins discussed. We were able explain results by adopting Landau-Ginzburg based computational approach coupled with elasticity electrostatics sites are treated point lattice. The gradual slanting hystereses reduction transition samples increasing claimed direct consequence electrical fields due formation dipolar defect complexes backed our simulations. ECE discussed light simulations recent AFE ceramics.