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We report the successful growth of square-like layered single crystals VOCl with a size of a few millimeters by chemical vapor transport method, and demonstrate that the layered crystals show good air stability and can be easily exfoliated. The atomic-resolution structure of the VOCl single crystals is consistent with the theoretical atomic models and the exfoliated VOCl flakes exhibit a uniform surface potential and a thickness-independent work function in the interval of 4–263 nm. Further magnetic measurements manifest that the VOCl crystal exhibit an N-type ferrimagnetic phase at 150 K and a compensation temperature of ~50 K. These findings not only enrich the magnetic family in layered materials but offer a platform for exploring new physics, and such study of microstructure, air stability, work function and magnetism in layered VOCl should push further the development of functionality tunable microwave devices or spintronics with all-layered materials.

As a typical, layered, so-called semimetal, vanadium diselenide (VSe2) is significantly different from other transition metal dichalcogenides (TMDs).

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The key bottlenecks preventing the practical application of the lithium–metal anode in the secondary batteries are the uncontrollable growth of dendritic Li and huge volume changes during cycling, which rapidly consume the electrolyte and incur short lifespan and poor electrochemical performance. In general, the use of three-dimensional (3D) porous scaffolds with high lithiophilicity is an effective way to solve these problems. Here, we report on a dendrite-free Li-metal anode enabled by an advanced 3D polypyrrole nanotube sponge (PPy-NS) as a Li host. The pyrrolic nitrogen functional groups guide uniform Li nucleation and growth with low overpotential. The conductive 3D skeleton effectively homogenizes the local electric field and Li-ion flux, further restraining dendrite formation. Benefiting from excellent Li deposition behavior, the 3D PPy-NS delivers a high Coulombic efficiency of 98.7% over 500 cycles and ultralong lifespan (1100 h) together with low overpotential (22 mV at 1 mA cm–2). Moreover, coupled with LiNi0.8Co0.1Mn0.1O2 cathodes, Li-metal full batteries show a remarkable capacity of 3.0 mA h cm–2 with 81.5% of the initial capacity over 140 cycles at discharging rate of 0.5 C under a lean electrolyte of 7 g A h–1 and negative/positive capacity ratio of 3. This work sheds light on designing and developing advanced 3D lithiophilic hosts for stable dendrite-free Li-metal batteries.

VSe is a typical layered semimetal TMDC, and was thought to be difficult to synthesize for many years. By changing the concentration of precursors and reaction steps in the hydrothermal method, here we successfully synthesize three different shapes of VSe: nano-hydrangea (NH), nano-dandelion (ND) and hexagonal disk (HD). The as-prepared VSe HDs have a single-crystalline structure compared with the poly-crystalline structure of NHs and NDs. The as-prepared VSe in these three shapes also demonstrates apparent differences and intrinsic properties both in the nitrogen adsorption-desorption characterizations and UV-vis absorption analysis. Possible growth processes and mechanisms are put forward in detail to further inspire shape-design in other nanoscale materials.

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The composition with V- or Ni-doped AlOOH nanorods drives FeNi and FeCo layered double hydroxides to obtain both high activity and better stability for the oxygen evolution reaction.