Van der Waals (vdW) stacking is a powerful technique to achieve desired properties in condensed matter systems through layer-by-layer crystal engineering. A remarkable example is the control over the twist angle between artificially-stacked vdW crystals, enabling the realization of unconventional phenomena in moiré structures ranging from superconductivity to strongly correlated magnetism. Here, we report the appearance of unusual 120° twisted faults in vdW magnet CrI crystals.
View Article and Find Full Text PDFCrystallization plays a critical role in determining crystal size, purity and morphology. Therefore, uncovering the growth dynamics of nanoparticles (NPs) atomically is important for the controllable fabrication of nanocrystals with desired geometry and properties. Herein, we conducted in situ atomic-scale observations on the growth of Au nanorods (NRs) by particle attachment within an aberration-corrected transmission electron microscope (AC-TEM).
View Article and Find Full Text PDFAlthough liquid mercury (Hg) has been known since antiquity, the formation of stable solid nano forms of Hg at room temperature has not been reported so far. Here, for the first time, we report a simple sonochemical route to obtain solid mercury nanoparticles, stabilized by reduced graphene oxide at ambient conditions. The as-formed solid Hg nanoparticles were found to exhibit remarkable rhombohedral morphology and crystallinity at room temperature.
View Article and Find Full Text PDFThe intercalation of layered compounds opens up a vast space of new host-guest hybrids, providing new routes for tuning the properties of materials. Here, it is shown that uniform and continuous layers of copper can be intercalated within the van der Waals gap of bulk MoS resulting in a unique Cu-MoS hybrid. The new Cu-MoS hybrid, which remains semiconducting, possesses a unique plasmon resonance at an energy of ≈1eV, giving rise to enhanced optoelectronic activity.
View Article and Find Full Text PDFThis study reports on the synthesis of highly oriented chromium triiodide (CrI) magnetic inclusions inside nano/microfibres with a polyethylene oxide matrix, prepared by the electrospinning technique. The structural, microstructural and spectroscopic analysis shows uniformly dispersed CrI nanosized inclusions inside the fibres, presenting a C2/m monoclinic structure at room temperature, where their c-axis is perpendicular to the fibre mat plane and the ab layers are in-plane. Analysis of the magnetic properties show that the samples have a ferromagnetic-paramagnetic phase transition at ∼55-56 K, lower than that of bulk CrI.
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