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Exploring the controllable aspects of local atomic structure and chemical ordering and their correlations with functional properties is crucial for harnessing the potential of complex oxides in the development of advanced materials. In this work, we have investigated the sensitivity of the magnetic properties in a nanostructured metastable spinel compositionally complex oxide (CCO) composition, (Mg0.2⁢Mn0.2⁢Fe0.2⁢Cu0.2⁢Zn0.2)⁢Co2⁢O4, to local chemical segregation and phase evolution introduced through variation in post-processing heat treatment temperature. A combination of x-ray diffraction, scanning transmission electron microscopy with energy dispersive x-ray spectroscopy, first-order reversal curve (FORC) magnetometry, and neutron diffraction and total scattering analyses was employed to understand both average and local structure-property evolution. Structure analysis shows that the postannealing process triggers local and long-range cation diffusion, resulting in changes in the distribution of atoms residing on the tetrahedral and octahedral sites of the spinel structure as well as nanoscale chemical heterogeneity. FORC analysis shows that redistribution of magnetic cations induces subtle magnetic phase separation and soft to hard magnetic phase transformations, and demonstrates incipient demixing of the as-synthesized material well before detection by neutron total scattering. This work additionally highlights the necessity of a combination of advanced characterization techniques for understanding the broader crystal-chemical class of compositionally complex oxides. 

A multifunctional filtration platform is demonstrated using metallic nanowire foams that are efficient, robust, antimicrobial, reusable, promising against multi-hazards. The foam microstructures are studied and correlated with filtration performance. 

The paper presents the hydrothermal synthesis, magnetic properties, and magnetic structure characterization of K₂Co₃(MoO₄)₃(OH)₂half sawtooth chains. 

The first-order reversal curve (FORC) method is a macroscopic measurement technique that can be used to extract quantitative and microscopic properties of hysteretic systems. Using magnetic transmission x-ray microscopy (MTXM), local element-specific FORC measurements are performed on a 20 nm thick film of CoTb. The FORCs measured with microscopy reveal a step-by-step domain evolution under the magnetic field cycling protocol and provide a direct visualization of the mechanistic interpretation of FORC diagrams. They are compared with magnetometry FORCs and show good quantitative agreement. Furthermore, the high spatial resolution and element-specific sensitivity of MTXM provide new capabilities to measure FORCs in small regions or specific phases within multicomponent systems, including buried layers in heterostructures. The ability to perform FORCs on very small features is demonstrated with the MTXM-FORC measurement of a rectangular microstructure with vortex-like Landau structures. This work demonstrates the confluence of two uniquely powerful techniques to achieve quantitative insight into nanoscale magnetic behavior. 

Thorium was a part of energy infrastructure in the 19th century due to the refractory and electronic properties of its dioxide. It will be a part of future energy infrastructure as the most abundant energy reserve based on nuclear fission. This paper discusses the solid-state chemistry of the monoxides and related rocksalt phases of thorium and the rare earths, both at atmospheric and at high pressure. The existence of solid thorium monoxide was first suggested more than 100 years ago; however, it was never obtained in bulk and has been studied mostly theoretically. Monoxides of lanthanides from Eu to Ho are ferromagnetic semiconductors sought for spintronics and were studied in thin films. La to Sm metallic monoxides were synthesized in bulk at pressures below 5 GPa. Recently, ThO formation in thin films has been reported and the stability of bulk ThO at high pressure was theoretically predicted based on first principles computations at 0 K. New ab initio computations were performed accounting for temperature effects up to 1000 K using lattice dynamics in the quasi-harmonic approximation. New computational results confirm the stabilization of pure ThO above 30 GPa and suggest the possibility of high-pressure synthesis of (Th,Nd)O at 1000 K and 5 GPa. 

We present an exploration of a family of compositionally complex cubic spinel ferrites featuring combinations of Mg, Fe, Co, Ni, Cu, Mn, and Zn cations, systematically investigating the average and local atomic structures, chemical short-range order, magnetic spin configurations, and magnetic properties. All compositions result in ferrimagnetic average structures with extremely similar local bonding environments; however, the samples display varying degrees of cation inversion and, therefore, differing apparent bulk magnetization. Additionally, first-order reversal curve analysis of the magnetic reversal behavior indicates varying degrees of magnetic ordering and interactions, including potentially local frustration. Finally, reverse Monte Carlo modeling of the spin orientation demonstrates a relationship between the degree of cation inversion and the spin collinearity. Collectively, these observations correlate with differences in synthesis procedures. This work provides a framework for understanding magnetic behavior reported for “high-entropy spinels,” revealing many are likely compositionally complex oxides with differing degrees of chemical short-range order—not meeting the community established criteria for high or medium entropy compounds. Moreover, this work highlights the importance of reporting complete sample processing histories and investigating local to long-range atomic arrangements when evaluating potential entropic mixing effects and assumed property correlations in high entropy materials.