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Despite great attention toward transition metal tellurates especially M3TeO6 (M = transition metal) in magnetoelectric applications, control on single phasic morphology-oriented growth of these tellurates at the nanoscale is still missing. Herein, a hydrothermal synthesis is performed to synthesize single-phased nanocrystals of two metal tellurates, i.e., Ni3TeO6 (NTO with average particle size ∼37 nm) and Cu3TeO6 (CTO ∼ 140 nm), using NaOH as an additive. This method favors the synthesis of pure NTO and CTO nanoparticles without the incorporation of Na at pH = 7 in MTO crystal structures such as Na2M2TeO6, as it happens in conventional synthesis approaches such as solid-state reaction and/or coprecipitation. Systematic characterization techniques utilizing in-house and synchrotron-based characterization methods for the morphological, structural, electronic, magnetic, and photoconductivity properties of nanomaterials showed the absence of Na in individual particulate single-phase MTO nanocrystals. Prepared MTO nanocrystals also exhibit slightly higher antiferromagnetic interactions (e.g., TN-NTO = 57 K and TN-CTO = 68 K) compared to previously reported MTO single crystals. Interestingly, NTO and CTO show not only a semiconducting nature but also photoconductivity. The proposed design scheme opens the door to any metal tellurates for controllable synthesis toward different applications. Moreover, the photoconductivity results of MTO nanomaterials prepared serve as a preliminary proof of concept for potential application as photodetectors. [ABSTRACT FROM AUTHOR]

A complex deposition process of high-temperature superconducting (HTS) thin films and coated conductors is usually optimized by concentrating on the crystalline quality of the material, thus getting the best possible critical temperature and self-field properties. However, most of the HTS power applications that are based on coated conductors act at high magnetic fields, and thus an alternative approach focusing on the formation of an optimal network of columnar flux pinning centers is more reasonable. Therefore, we systematically show how a lengthening of the deposition distance produces perfectly aligned and distinctly longer self-assembled BaZrO3 (BZO) nanorods within the YBa2Cu3O6+x (YBCO) matrix. This method unambiguously enhances in-field properties such as pinning force, critical current density, and its isotropy along the YBCO c axis. The experimental results, especially formation of the c peak where the relative length of the nanorod is a key issue, are confirmed by the vortex dynamics simulations. Finally, we present a semiquantitative model governing the formation of nanorods that explains the experimentally observed improved nanorod growth as a function of the deposition distance via the associated variation of the fractional partial pressure between atomic species within the laser plume. [ABSTRACT FROM AUTHOR]

Despite great attention toward transition metal tellurates especially M 3 TeO 6 (M = transition metal) in magnetoelectric applications, control on single phasic morphology-oriented growth of these tellurates at the nanoscale is still missing. Herein, a hydrothermal synthesis is performed to synthesize single-phased nanocrystals of two metal tellurates, i.e., Ni 3 TeO 6 (NTO with average particle size ∼37 nm) and Cu 3 TeO 6 (CTO ∼ 140 nm), using NaOH as an additive. This method favors the synthesis of pure NTO and CTO nanoparticles without the incorporation of Na at pH = 7 in MTO crystal structures such as Na 2 M 2 TeO 6 , as it happens in conventional synthesis approaches such as solid-state reaction and/or coprecipitation. Systematic characterization techniques utilizing in-house and synchrotron-based characterization methods for the morphological, structural, electronic, magnetic, and photoconductivity properties of nanomaterials showed the absence of Na in individual particulate single-phase MTO nanocrystals. Prepared MTO nanocrystals also exhibit slightly higher antiferromagnetic interactions (e.g., T N -NTO = 57 K and T N -CTO = 68 K) compared to previously reported MTO single crystals. Interestingly, NTO and CTO show not only a semiconducting nature but also photoconductivity. The proposed design scheme opens the door to any metal tellurates for controllable synthesis toward different applications. Moreover, the photoconductivity results of MTO nanomaterials prepared serve as a preliminary proof of concept for potential application as photodetectors., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)