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Title: Exploring the Pb 1− x Sr x HfO 3 System and Potential for High Capacitive Energy Storage Density and Efficiency
Abstract

The hafnate perovskites PbHfO3(antiferroelectric) and SrHfO3(“potential” ferroelectric) are studied as epitaxial thin films on SrTiO3(001) substrates with the added opportunity of observing a morphotropic phase boundary (MPB) in the Pb1−xSrxHfO3system. The resulting (240)‐oriented PbHfO3(Pba2) films exhibited antiferroelectric switching with a saturation polarization ≈53 µC cm−2at 1.6 MV cm−1, weak‐field dielectric constant ≈186 at 298 K, and an antiferroelectric‐to‐paraelectric phase transition at ≈518 K. (002)‐oriented SrHfO3films exhibited neither ferroelectric behavior nor evidence of a polarP4mmphase . Instead, the SrHfO3films exhibited a weak‐field dielectric constant ≈25 at 298 K and no signs of a structural transition to a polar phase as a function of temperature (77–623 K) and electric field (–3 to 3 MV cm−1). While the lack of ferroelectric order in SrHfO3removes the potential for MPB, structural and property evolution of the Pb1−xSrxHfO3(0 ≤x < 1) system is explored. Strontium alloying increased the electric‐breakdown strength (EB) and decreased hysteresis loss, thus enhancing the capacitive energy storage density (Ur) and efficiency (η). The composition, Pb0.5Sr0.5HfO3produced the best combination ofEB = 5.12 ± 0.5 MV cm−1,Ur = 77 ± 5 J cm−3, and η = 97 ± 2%, well out‐performing PbHfO3and other antiferroelectric oxides.

 
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Award ID(s):
1708615
NSF-PAR ID:
10361827
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials
Volume:
34
Issue:
1
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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