GERMANIUM DISULFIDE

• CAS: 12025-34-2
• Catalog Number: ACM12025342-5
• Category: Main Products
• Molecular Weight: 136.77
• Molecular Formula: GeS2
• Synonyms: AC1L345Z; AR-1I6763; dithioxogermane; GERMANIUM DISULFIDE; Germanium disulphide; Germanium sulfide (GeS2); AC1Q7EE9; EINECS 234-705-1
• IUPAC Name: bis(sulfanylidene)germane
• Canonical SMILES: S=[Ge]=S
• InChI Key: YIZVROFXIVWAAZ-UHFFFAOYSA-N
• Melting Point: 725ºC
• Appearance: White translucent crystals
• EC Number: 234-705-1
• Exact Mass: 139.88100

Case Study

High-Pressure and High-Temperature Studies of Germanium Disulfide and Germanium Diselenide

Kulikova, L. F., et al. Inorganic Materials, 2014, 50, 768-774.

GeX (X = S, Se) germanium dichalcogenides have unique electronic and optical properties and show potential for state-of-the-art optoelectronic device applications. This work explores the phase transitions of GeX2 (X = S, Se) dichalcogenides at pressures up to p≈8 GPa and temperatures from 675 to 1375 K, and constructs a partial p-T phase diagram of them.
Phase transitions of germanium dichalcogenides
· The GeS2-II and GeSe2-II phases have been confirmed to crystallize in the α-ZnCl2 structure based on data analysis. The unit cell parameters for the high pressure phase GeS2-III are a = 3.46906(2) Å, c = 10.9745(1) Å (HgI2 structure). It appears that the structural determination of GeSe2-III in prior studies may have been inaccurate, given the lower density of the GeSe2-III high pressure phase compared to GeSe2-I.
· When looking at the phase diagrams of GeS2 and GeSe2 compounds, it is noted that they are quite similar at moderate pressures (up to 5 GPa) but differ significantly at higher pressures. The р-Т phase diagrams show distinct slope differences in the equilibrium lines between GeS2-II-GeS2-III and GeSe2-II-GeSe2-III phases, reflecting variations in their structures. Initial findings propose that under high pressures, GeSe2-III behaves as a metal while GeS2-III remains a dielectric. The transition from GeSe2-II to GeSe2-III causing metallization is likely the reason for the nearly zero or positive entropy change and the slope of the transformation line.

Synthesis of Ultrathin Germanium Disulfide Nanosheets and Their Application in Sodium-Ion Batteries

Li, Cheng Chao, et al. ACS nano, 2019, 14(1), 531-540.

Two-dimensional ultrathin germanium disulfide (GeS2) nanosheets (thickness: ~1.2 nm) were prepared by a topological chemical transformation strategy. They exhibited excellent sodium storage performance and can be used as anode materials for sodium-ion batteries (SIBs). SIB full cell was constructed with GeS2 nanosheet electrode and Na3V2(PO4)2O2F cathode, with an energy density of up to 213 Wh kg -1.
Synthesis of Ultrathin GeS2 Nanosheets
· The process of creating ultrathin GeS2 nanosheets involved a series of steps. Initially, a mixture of Ca and Ge commercial powders in a 1:2 molar ratio was combined and sealed in a quartz tube using an oxy-hydrogen flame machine. This mixture was then heated to 1050 °C for 20 hours to form bulk CaGe2.
· To obtain germanium nanosheets, the Ca was removed by immersing CaGe2 in concentrated hydrochloric acid for several days. The germanium nanosheets were then sulfured with sulfur powder in a vacuum-sealed quartz tube at 800 °C for 6 hours. Finally, the ultrathin GeS2 nanosheets were achieved after thorough washing with CS2 and ethanol.