Rapid, energy-efficient and pseudomorphic microwave-induced-metal-plasma (MIMP) synthesis of Mg₂Si and Mg₂Ge

Abstract

Polycrystalline magnesium silicide, Mg2Si and magnesium germanide, Mg2Ge were synthesised from the elemental powders via the microwave-induced-metal-plasma (MIMP) approach at 200 W within 1 min in vacuo for the first...

Hierarchical nanoporous Ge anodes for lithium-ion batteries via plasma-phase-fabricated Mg2Ge

“…5,11,25,38 Previously, we conceived the MIMP method for the synthesis of alloys from metals, by which ultra-rapid reactions were driven by metal plasma interactions in a 2.45 GHz electromagnetic field. 5,9,39 Here, we first show how the concept can be applied to the conversion of an oxide (GeO 2 ) directly to an alloy (Mg 2 Ge) by a MW-induced Mg plasma (Scheme 1; see also the experimental Section; full details in the ESI †). Mixtures of fine Mg and GeO 2 powders were irradiated by MWs (200 W) in a single-mode cavity reactor under a static vacuum of 1.0 Â 10 À1 mbar.…”

“…Mixtures of fine Mg and GeO 2 powders were irradiated by MWs (200 W) in a single-mode cavity reactor under a static vacuum of 1.0×10 -1 mbar. A green Mg plasma -which can be conceived as positively charged Mg cations, metastable neutral Mg clusters and negatively charged electrons 5,9,39 -was observed within seconds of the onset of MW irradiation (ESI -Supporting Videos 1, 2), indicating efficient ohmic coupling of the Mg powders with MWs. Ex-situ powder X-ray diffraction (PXD) patterns (Figure 1) indicate that most of Scheme 1.…”