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1. Influence of Al‐doped SrTiO ₃ cores on hydrogen evolution from SrTiO ₃ /TiO ₂ core‒shell catalysts

   https://doi.org/10.1111/jace.20542  

   Song, Wenjia; Salvador, Paul_A; Rohrer, Gregory_S (April 2025, Journal of the American Ceramic Society)

   Abstract The hydrogen produced by Al‐doped SrTiO₃/TiO₂core‒shell catalysts with a range of Al‐doped SrTiO₃cores and the same TiO₂shell are compared. The study included SrTiO₃cores doped with different amounts of Al (0, 1, 2, or 3 mol%) added at different points in the synthesis (prior to or during the molten salt treatment) and at different temperatures (900°C, 1000°C, and 1100°C). It was found that core‒shell catalysts with different cores had hydrogen generation rates that varied by a factor of more than 40 and varied with the processing parameters in the same way as the hydrogen generation rates of the cores alone. The best catalysts had 2 or 3 mol% added Al, added during treatment in a SrCl₂molten salt at 1000°C or 1100°C. Because the core absorbs most of the light, its ability to separate and transport photogenerated charge carriers dominates the properties of the core‒shell catalyst. This indicates that, to optimize the properties of core‒shell catalysts, it is essential to optimize the properties of the core. While the shell can be important to protect the core from degradation, it is not as important to the overall reactivity as the core. 

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2. High Current Density SmTiO ₃ /SrTiO ₃ Field-Effect Transistors

   https://doi.org/10.1021/acsaelm.9b00738  

   Chandrasekar, Hareesh; Ahadi, Kaveh; Razzak, Towhidur; Stemmer, Susanne; Rajan, Siddharth (January 2020, ACS Applied Electronic Materials)

   null (Ed.)
3. Domain alignment within ferroelectric/dielectric PbTiO ₃ /SrTiO ₃ superlattice nanostructures

   https://doi.org/10.1039/c7nr07203a  

   Park, Joonkyu; Mangeri, John; Zhang, Qingteng; Yusuf, M. Humed; Pateras, Anastasios; Dawber, Matthew; Holt, Martin V.; Heinonen, Olle G.; Nakhmanson, Serge; Evans, Paul G. (January 2018, Nanoscale)

   The ferroelectric domain pattern within lithographically defined PbTiO 3 /SrTiO 3 ferroelectric/dielectric heteroepitaxial superlattice nanostructures is strongly influenced by the edges of the structures. Synchrotron X-ray nanobeam diffraction reveals that the spontaneously formed 180° ferroelectric stripe domains exhibited by such superlattices adopt a configuration in rectangular nanostructures in which domain walls are aligned with long patterned edges. The angular distribution of X-ray diffuse scattering intensity from nanodomains indicates that domains are aligned within an angular range of approximately 20° with respect to the edges. Computational studies based on a time-dependent Landau–Ginzburg–Devonshire model show that the preferred direction of the alignment results from lowering of the bulk and electrostrictive contributions to the free energy of the system due to the release of the lateral mechanical constraint. This unexpected alignment appears to be intrinsic and not a result of distortions or defects caused by the patterning process. Our work demonstrates how nanostructuring and patterning of heteroepitaxial superlattices allow for pathways to create and control ferroelectric structures that may appear counterintuitive. 

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4. Tailoring LaAlO ₃ /SrTiO ₃ Interface Metallicity by Oxygen Surface Adsorbates

   https://doi.org/10.1021/acs.nanolett.6b00421  

   Dai, Weitao; Adhikari, Sanjay; Garcia-Castro, Andrés Camilo; Romero, Aldo H.; Lee, Hyungwoo; Lee, Jung-Woo; Ryu, Sangwoo; Eom, Chang-Beom; Cen, Cheng (April 2016, Nano Letters)
5. Enhancing superconductivity in SrTiO ₃ films with strain

   https://doi.org/10.1126/sciadv.aaw0120  

   Ahadi, Kaveh; Galletti, Luca; Li, Yuntian; Salmani-Rezaie, Salva; Wu, Wangzhou; Stemmer, Susanne (April 2019, Science Advances)

   The nature of superconductivity in SrTiO 3 , the first oxide superconductor to be discovered, remains a subject of intense debate several decades after its discovery. SrTiO 3 is also an incipient ferroelectric, and several recent theoretical studies have suggested that the two properties may be linked. To investigate whether such a connection exists, we grew strained, epitaxial SrTiO 3 films, which are known to undergo a ferroelectric transition. We show that, for a range of carrier densities, the superconducting transition temperature is enhanced by up to a factor of two compared to unstrained films grown under the same conditions. Moreover, for these films, superconductivity emerges from a resistive state. We discuss the localization behavior in the context of proximity to ferroelectricity. The results point to new opportunities to enhance superconducting transition temperatures in oxide materials. 

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