More Like this

1. One-Step Solvothermal Synthesis of Perovskite-Type Li _3x La _2/3–x □ _1/3–2x TiO ₃ Nanomaterials

   https://doi.org/10.1021/acs.chemmater.4c01349  

   Dato, Michael A; Hu, Linhua; McElheny, Dan; Cabana, Jordi (September 2024, Chemistry of Materials)
2. Engineering Relaxor Behavior in (BaTiO ₃ ) _n /(SrTiO ₃ ) _n Superlattices

   https://doi.org/10.1002/adma.202302012  

   Lupi, Eduardo; Wexler, Robert B.; Meyers, Derek; Zahradnik, Anton; Jiang, Yizhe; Susarla, Sandhya; Ramesh, Ramamoorthy; Martin, Lane W.; Rappe, Andrew M. (November 2023, Advanced Materials)

   Abstract Complex‐oxide superlattices provide a pathway to numerous emergent phenomena because of the juxtaposition of disparate properties and the strong interfacial interactions in these unit‐cell‐precise structures. This is particularly true in superlattices of ferroelectric and dielectric materials, wherein new forms of ferroelectricity, exotic dipolar textures, and distinctive domain structures can be produced. Here, relaxor‐like behavior, typically associated with the chemical inhomogeneity and complexity of solid solutions, is observed in (BaTiO₃)_n/(SrTiO₃)_n(n= 4–20 unit cells) superlattices. Dielectric studies and subsequent Vogel–Fulcher analysis show significant frequency dispersion of the dielectric maximum across a range of periodicities, with enhanced dielectric constant and more robust relaxor behavior for smaller periodn. Bond‐valence molecular‐dynamics simulations predict the relaxor‐like behavior observed experimentally, and interpretations of the polar patterns via 2D discrete‐wavelet transforms in shorter‐period superlattices suggest that the relaxor behavior arises from shape variations of the dipolar configurations, in contrast to frozen antipolar stripe domains in longer‐period superlattices (n= 16). Moreover, the size and shape of the dipolar configurations are tuned by superlattice periodicity, thus providing a definitive design strategy to use superlattice layering to create relaxor‐like behavior which may expand the ability to control desired properties in these complex systems. 

   more » « less
3. Detection of 1 H -Triphosphirene ( c -HP ₃ ) and 2-Triphosphenylidene (HP ₃ ): The Isovalent Counterparts of 1 H -Triazirine ( c -HN ₃ ) and Hydrazoic Acid (HN ₃ )

   https://doi.org/10.1021/acs.jpclett.2c00639  

   Zhang, Chaojiang; Zhu, Cheng; Eckhardt, André K.; Kaiser, Ralf I. (March 2022, The Journal of Physical Chemistry Letters)
4. a -axis YBa ₂ Cu ₃ O _7−x /PrBa ₂ Cu ₃ O _7−x /YBa ₂ Cu ₃ O _7−x trilayers with subnanometer rms roughness

   https://doi.org/10.1063/5.0034648  

   Suyolcu, Y. Eren; Sun, Jiaxin; Goodge, Berit H.; Park, Jisung; Schubert, Jürgen; Kourkoutis, Lena F.; Schlom, Darrell G. (February 2021, APL Materials)

   null (Ed.)
5. Strengthened relaxor behavior in (1− x )Pb(Fe _0.5 Nb _0.5 )O ₃ – x BiFeO ₃

   https://doi.org/10.1039/C9TC05883D  

   Prah, Uroš; Dragomir, Mirela; Rojac, Tadej; Benčan, Andreja; Broughton, Rachel; Chung, Ching-Chang; Jones, Jacob L.; Sherbondy, Rachel; Brennecka, Geoff; Uršič, Hana (March 2020, Journal of Materials Chemistry C)

   null (Ed.)

   A systematic study of (1− x )Pb(Fe 0.5 Nb 0.5 )O 3 – x BiFeO 3 ( x = 0–0.5) was performed by combining dielectric and electromechanical measurements with structural and microstructural characterization in order to investigate the strengthening of the relaxor properties when adding BiFeO 3 into Pb(Fe 0.5 Nb 0.5 )O 3 and forming a solid solution. Pb(Fe 0.5 Nb 0.5 )O 3 crystalizes in monoclinic symmetry exhibiting ferroelectric-like polarization versus electric field ( P–E ) hysteresis loop and sub-micron-sized ferroelectric domains. Adding BiFeO 3 to Pb(Fe 0.5 Nb 0.5 )O 3 favors a pseudocubic phase and a gradual strengthening of the relaxor behavior of the prepared ceramics. This is indicated by a broadening of the peak in temperature-dependent permittivity, narrowing of P–E hysteresis loops and decreasing size of ferroelectric domains resulting in polar nanodomains for x = 0.20 composition. The relaxor behavior was additionally confirmed by Vogel–Fulcher analysis. For the x ≥ 0.30 compositions, broad high-temperature anomalies are observed in dielectric permittivity versus temperature measurements in addition to the frequency-dispersive peak located close to room temperature. These samples also exhibit pinched P–E hysteresis loops. The observed pinching is most probably related to the reorganization of polar nanoregions under the electric field as shown by synchrotron X-ray diffraction measurements as well as by piezo-response force microscopy analysis, while in part affected by the presence of charged point defects and anti-ferroelectric order, as indicated from rapid cooling experiments and high-resolution transmission electron microscopy, respectively. 

   more » « less