FURI | Fall 2020

Germanium Dioxide: Development of Synthesis Techniques

Germanium dioxide has known bulk properties but has not been synthesized in a thin film form. Materials take on vastly different properties when they are on the nano-scale. These have been utilized in many ways such as batteries, insulation, medicine, transportation, and optics[1]. Previous research by the Wang Research Group[2] showed that molybdenum trioxide (MoO3) and tungsten trioxide (WO3) could be synthesized from their respective sulfides MoS2 and WS2 by an atmospheric plasma treatment. This FURI project aims to use a similar synthesis method to convert thin-film germanium disulfide (GeS2) into thin-film germanium oxides (GeOx). Mechanical exfoliation is used to prepare atomically thin sheets of GeS2 that are then characterized with Raman spectroscopy and atomic force microscopy (AFM). Subsequently, these samples are exposed to atmospheric plasma with the hypothesis that this will form thin-film GeOx where x represents the most favorable thin-film germanium oxide stoichiometry. Initial experiments have shown that unique bonding states and morphologies are achieved with this synthesis method while the mechanism and specific identity of these initial materials is unknown. Further characterization methods of x-ray photoelectron spectroscopy are planned to identify the exact stoichiometry of the material.

Sources

[1] Nano Technology Initiative 2000, accessed September 26th, 2020, <https://www.nano.gov/you/nanotechnology-benefits>

[2] Wang, Q. H.,  Chu, X. S., Li, D. O., Green, A. A. (2017). Formation of MoO3 and WO3 nanoscrolls from MoS2 and WS2 with atmospheric air plasma. Journal of Materials Chemistry C., Vol.(5) pg 11301 – 11309. DOI: 10.1039/c7tc02867a