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Atomic-scale intercalation and defect engineering for enhanced magnetism and optoelectronic properties in atomically thin GeS
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Control of crystal size tailors the electrochemical performance of α-V 2 O 5 as a Mg 2+ intercalation host
Nanosizing α-V 2 O 5 inhibits delamination during cycling in Mg electrolytes, reducing the voltage hysteresis and energy loss on the first cycle. This observation indicates that other factors, not just Mg diffusion, contribute to this energy loss.
Strategies to alleviate distortive phase transformations in Li-ion intercalation reactions: an example with vanadium pentoxide
This mini-review highlights recent materials design strategies to alleviate distortive phase transformations in vanadium pentoxide materials for energy storage applications and characterization methods.
Li-ion and Na-ion intercalation in layered MnO 2 cathodes enabled by using bismuth as a cation pillar
Low-cost batteries based on Earth-abundant materials are needed for large-scale electrical storage for the grid. Cathodes based almost entirely on Mn oxides would reduce overall battery cost but cycling of Mn oxides is often not stable. In Li-ion cells, most polymorphs of MnO 2 undergo irreversible transformation to spinel LiMn 2 O 4 during cycling, causing capacity loss. Doping MnO 2 with Bi is known to stabilize the structure, but previous reports have relied on low-crystallinity material making it impossible to pinpoint the Bi location in the structure or its mechanism. In this work, we report a series of hydrated Bi-doped layered MnO 2 compounds and characterize their structures as a function of Bi amount. Bi is shown to reside in the material interlayer, provoking higher long-range structural order even at a low doping level of 1.3%. Doped material improves the specific capacity and stability of cycling in both Li-ion and Na-ion cells. A high level of Bi doping, 4.3%, causes loss of the interlayer crystal water in non-aqueous electrolyte, and this reduces the interlayer distance. Crystal water is shown to be beneficial in a Na-ion system, while its loss improves Li-ion cycling. This provides fundamental insight into how pillaring by a heavy, multivalent cation stabilizes layered oxides.
Probing local electronic and geometric changes of hydrated calcium vanadium oxide (CaxV2O5·yH2O) upon Zn ion intercalation
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Three-dimensional ferromagnetism and magnetotransport in van der Waals Mn-intercalated tantalum disufide
Van der Waals (vdW) ferromagnets are an important class of materials for spintronics applications. The recent discovery of atomically vdW magnets CrI 3 and Cr 2 Ge 2 Te 6 has triggered a renaissance in the area of two-dimensional (2D) magnetism. Herein we systematically studied 2H-Mn 0.28 TaS 2 single crystal, a 2D vdW ferromagnet with T c ~ 82.3K, and a large in-plane magnetic anisotropy. Mn K-edge x-ray absorption spectroscopy was measured to provide information on its electronic state and local atomic environment. The detailed magnetic isotherms measured in the vicinity of T c indicates that the spin coupling inside 2H-Mn 0.28 TaS 2 is of a 3D Heisenberg type coupled with the attractive long-range interaction between spins that decay as J(r) ≈ r –4.85 . Both resistivity ρ(T) and thermopower S(T) exhibit anomalies near T c , confirming that the hole-type transport carriers strongly interact with local moments. Furthermore, an unusual angle-dependent magnetoresistance is further observed, suggesting a possible field-induced novel magnetic structure.
DFT + DMFT study of the magnetic susceptibility and the correlated electronic structure in transition-metal intercalated NbS 2
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Composition dependence of bulk properties in the Co-intercalated transition metal dichalcogenide $\mathrm{Co_{1/3}TaS_2}$
Spontaneous Hall conductivity has recently been reported in the triangular lattice antiferromagnet Co 1/3 TaS 2 under a zero magnetic field. This phenomenon originates from the distinctive noncoplanar triple-Q magnetic ground state, possessing uniform real-space Berry curvature characterized by scalar spin chirality. We investigated the physical properties of Co 1/3 TaS 2 by judiciously controlling the composition, revealing a drastic change in its bulk properties, even by slight variations in cobalt composition, despite the same crystal structure. For 0.299≤x≤0.325, Co x TaS 2 keeps all the characteristics of the ground state consistent with the previous studies—two antiferromagnetic phase transitions at T N1 and T N2 ( N1 ), a large spontaneous Hall conductivity [σ xy (H=0)], and a weak ferromagnetic moment along the c axis. However, samples with x≥0.330 exhibit distinct bulk properties, including the absence of both σ xy (H=0) and the weak ferromagnetic moment. Our neutron diffraction data reveal that Co x TaS 2 with x≥0.330 develops coplanar helical magnetic order with q m1 =(1/3, 0, 0). This is entirely different from what has been seen in x≤0.325, explaining the observed composition dependence.
Observation of intercalation-driven zone folding in quasi-free-standing graphene energy bands
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First-principles analysis of intercalated Pb structures under buffer-layer graphene on SiC(0001): Pb(111)-, plumbene-, and amorphous-like Pb layers
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Magnetic evolution induced by freezing of Ag + fluctuations in an intercalated transition metal dichalcogenide
Here, we present a comprehensive study on the magnetic evolution processes in AgCrSe 2 using both neutron scattering and theoretical calculations. Additionally, the development of magnetic short-range correlation with decoupled interlayer interactions is confirmed between 55 and 200 K. Significant magneto-crystalline anisotropy energy around 0.1 meV of Cr 3+ is identified that mainly contributes to the robust existence of the in-plane magnetic correlations in the magnetic short-order regime. Furthermore, the indirect superexchange interactions through Cr-Se-Ag-Se-Cr path between the adjacent CrSe 6 octahedral layers is also demonstrated. In combination with the mutual coupling among multiple degrees of freedom (spin, phonon, lattice, and dipole), we reveal the key role of the freezing of Ag + fluctuations in preventing interlayer exchange interactions from decoupling.
Adsorption, intercalation, diffusion, and adhesion of Cu at the 2 H − Mo S 2 (0001) surface from first-principles calculations
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Impact of disorder in the charge density wave state of Pd-intercalated ErTe 3 revealed by the electrodynamic response
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Emergent Ferromagnetism with Fermi-Liquid Behavior in Proton Intercalated CaRuO 3
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Roller Coaster in a Flatland: Magnetoresistivity in Eu-Intercalated Graphite
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