Abstract
We report on the phase formation and the superconducting properties in the NbS2system. Specifically, we have performed a series of standardized solid-state syntheses in this system, which allow us to establish a comprehensive synthesis map for the formation of the two polytypes 2H-NbS2and 3R-NbS2, respectively. We show that the identification of two polytypes by means of X-ray diffraction is not always unambiguous. Our physical property measurements on a phase-pure sample of 3R-NbS2, on a phase-pure sample of 2H-NbS2, and a mixed phase sample confirm earlier reports that 2H-NbS2is a bulk superconductor and that 3R-NbS2is not a superconductor aboveT= 1.75 K. Our results clearly show that specific heat measurements, as true bulk measurements, are crucial for the identification of superconducting materials in this and related systems. Our results indicate that for the investigation of van der Waals materials great care has to be taken on choosing the synthesis conditions for obtaining phase pure samples.
| Original language | English |
|---|---|
| Pages (from-to) | 3216-3223 |
| Number of pages | 8 |
| Journal | Dalton Transactions |
| Volume | 50 |
| Issue number | 9 |
| DOIs | |
| State | Published - Mar 7 2021 |
| Externally published | Yes |
Funding
The authors thank Manuele Balestra and Mark Blumer for help during the synthesis. The authors thank Dr Robin Lefèvre for helpful discussions. This work was supported by the Swiss National Science Foundation under grant no. PZ00P2_174015 and PCEFP2_194183. Work at GUT was supported by the National Science Centre (Poland), grant number: UMO-2017/ 27/B/ST5/03044. This research is also funded by the Swedish Research Council (VR) through a neutron project grant Dnr. 2016-06955.