Recently, we reported the HER activity of Fe3GeTe2 (FGT), a van der Waals (vdW) material which exhibited both basal plane and edge site activity. Sonicated FGT that was compressed by spark plasma sintering (SPS) yielded the greatest activity relative to the bulk and sonicated forms by providing the most electrode coverage. Expanding on this, we now report on the HER activity of Fe5Ge2Te2 (FG2T), a material analogous to FGT.
FG2T was synthesized via a solid-state reaction and characterized by powder X-ray diffraction (PXRD), scanning electron microscope (SEM), and energy dispersive X-ray spectroscopy (EDS) mapping. Using a sonicated SPS sample, we show that FG2T requires an overpotential of −90.5 mV to drive a current density of 10 mA/cm2, a 13% increase compared to FGT. Density functional theory (DFT) revealed more active sites versus FGT, strengthening the idea of the continued screening of iron-based vdW materials.