Latest progress on new lead-free antiferroelectric compositions

Material design guided by DFT calculations

2021/01/19 by

Prototype NN and modified NN-SS: electrical properties and local chemical environment.

In our recent publication entitled “Design of Lead-Free Antiferroelectric (1 – x)NaNbO3–xSrSnO3 Compositions Guided by First-Principles Calculations” (Chem. Mater. 2021, 33, 1, 266–274), Zhang et al. produced a new NaNbO3-based antiferroelectric material that exhibits reversible antiferroelectric to ferroelectric phase transition under the guidance of DFT calculations.

According to their DFT calculations, the ferroelectric order is more energetically stable than the antiferroelectric order by an energy difference of 2.3 meV/f.u. in NaNbO3 while SrSnO3 is predicted to stabilize the antiferroelectric order in NaNbO3 by an energy difference of 1.4 meV/f.u. when 6.25 mol.% of SrSnO3 is incorporated. They processed a series of SrSnO3-modified NaNbO3 ceramic materials using solid-state reactions. It was found that the irreversible antiferroelectric-ferroelectric phase transition in NaNbO3 becomes reversible in SrSnO3-modified new materials. Detailed structural characterizations revealed an increase the unit cell volume and a more disordered, yet less distorted local Na environment, which were related to the stabilization of the antiferroelectric order.

Publication:

Chemistry of Materials, 33 (1), S. 266-274

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