Controllable Growth of 2D V₃S₅ Single Crystal by Chemical Vapor Deposition

Abstract

Abstract2D intercalated vanadium chalcogenides have attracted intensive interest based on their physical properties and potential applications. However, controllable synthesis of the intercalated vanadium chalcogenides via chemical vapor deposition is still a big challenge. Here, a binary metal precursor co‐reaction growth mechanism to manipulate the evaporation rate of vanadium precursors is reported, thus the intercalated 2D V1+XS2 – V3S5 single crystal can be controllably synthesized. The quality of 2D V3S5 nanosheets is identified by Raman spectroscopy and high‐resolution scanning transmission electron microscopy. Interestingly, a phase transition in 2D metallic V3S5 nanosheets is observed at 20 K. Meanwhile, the resistance upturn and unsaturated negative magnetoresistance induced by electron–electron interaction is confirmed. This work proposes a new strategy to synthesize the 2D intercalated VxSy single crystals with different compositions for studying their excellent properties and potential applications.

Phase and Composition Engineering of Self-Intercalated 2D Metallic Tantalum Sulfide for Second-Harmonic Generation

“…As depicted in Figure S5a−d, the thickness of ic-2D Ta 1+x S 2 flakes varied from 1.8 to 57.5 nm. 13,41,44 On the other hand, our analysis revealed that ic-2D TaS 2 flakes transform from irregular triangles to curved or truncated triangles and even hexagons. The thickness ranges from 2.7 to 36.0 nm, which was tuned by the modulation of hydrogen concentration (Figure S4h−k and Figure S5e−h).…”

“…Notably, upon the intercalation of Ta atoms into the vdW gaps whether ordered or disordered, the centrosymmetry of T-TaS 2 is prone to be broken, due to a transformation to non-centrosymmetry or the absence of longrange periodicity (Figure S13b and c). 44 Consequently, the assynthesized ic-2D T-Ta 1+x S 2 , featuring disordered intercalated Ta atoms, is expected to exhibit a significant SHG response via disordered intercalation, attributed to the broken inversion symmetry of pure T-TaS 2 (Figure S13d).…”

Chemical Vapor Deposition Synthesis of Intrinsic High‐Temperature Ferroelectric 2D CuCrSe2

“…At low reaction temperature of Se and low Ar flow rate, the partial vapor pressure of Se and metallic precursors can be modulated for preparing stoichiometric CuCrSe 2 . [38,39] We used atomic force microscopy (AFM) to check the thickness of CuCrSe 2 nanosheet. Figure 1e shows the ultrathin CuCrSe 2 with the thickness of 2 nm, which can be considered as a one-unit cell (1 u.c.)…”

Research Progress on Vanadium Sulfide Anode Materials for Sodium and Potassium‐Ion Batteries

“…Vanadium sulfide encompasses several phases, notably including VS 2 , VS 4 , V 2 S 5 , V 2 S 3 , VS, V 3 S 4 , V 3 S 5 , and V 5 S 8 . [ 21,37–42 ] Among these, owing to their exceptionally high theoretical specific capacity, VS 2 and VS 4 have gained significant prominence as anode materials in SIBs and PIBs. The crystal structure of VS 2 is characterized by layering with a layer spacing of 5.76 Å.…”

“…It's important to note that the oxidation state of vanadium remains constant in both VS 2 and VS 4 , while the oxidation state of the sulfide differs, with VS 2 containing S 2 ⁻ monomers and VS 4 featuring S 2 2 ⁻ dimers. With respect to the NiAs‐type VS x compounds, including V 2 S 3 , V 3 S 4 , V 3 S 5 , and V 5 S 8 , these crystal structures formed by self‐ intercalated of either V or VS. [ 37,38,43–45 ] Moreover, it is significant that compounds in the NiAs‐type VS x structural class frequently exhibit a predominance of polar and covalent bonding as opposed to ionic interactions. This is because internal instability can result from ionic interactions that are affected by cation‐cation repulsion.…”