High-Pressure Control of Vanadium Self-Intercalation and Enhanced Metallic Properties in 1T-V1+xS2 Single Crystals.
By means of high-pressure synthesis in the 4-6 GPa range, we report on the successful growth of high-quality 1T-V1+xS2 single crystals with controlled concentration, x = 0.09-0.17, of self-intercalated V atoms in the van der Waals gap. A systematic X-ray diffraction and energy-dispersive X-ray spectroscopy study unveils a linear decrease of x with the synthesis pressure, dx/dP = -0.042 GPa(-1), suggesting that the stoichiometric (x = 0) phase is stable above 8 GPa. Transmission electron microscopy and electrical resistivity measurements show that, for all x values studied, the system is metallic up to 400 K, with no charge-density-wave order, contrary to the x = 0 composition. This finding clarifies the controversial electronic phase diagram of the 1T-V1+xS2 system and unveils a connection between the charge-density-wave phase observed at x = 0 and the itinerant antiferromagnetic phase stable for x > 0.25.
Sorbonne Universités - UPMC, CNRS, IRD, MNHN, IMPMC , 4 place Jussieu, 75005 Paris, France.
Hicham
H
Moutaabbid
Sorbonne Universités - UPMC, CNRS, IRD, MNHN, IMPMC , 4 place Jussieu, 75005 Paris, France.
Yann
Y
Le Godec
Sorbonne Universités - UPMC, CNRS, IRD, MNHN, IMPMC , 4 place Jussieu, 75005 Paris, France.
Dario
D
Taverna
Sorbonne Universités - UPMC, CNRS, IRD, MNHN, IMPMC , 4 place Jussieu, 75005 Paris, France.
Benoı̂t
B
Baptiste
Sorbonne Universités - UPMC, CNRS, IRD, MNHN, IMPMC , 4 place Jussieu, 75005 Paris, France.
Yannick
Y
Klein
Sorbonne Universités - UPMC, CNRS, IRD, MNHN, IMPMC , 4 place Jussieu, 75005 Paris, France.
Geneviève
G
Loupias
Sorbonne Universités - UPMC, CNRS, IRD, MNHN, IMPMC , 4 place Jussieu, 75005 Paris, France.
Andrea
A
Gauzzi