Abundant Active Sites on the Basal Plane and Edges of Layered van der Waals Fe3GeTe2 for Highly Efficient Hydrogen Evolution

van der Waals (vdW) metal chalcogenides have been extensively investigated as electrocatalysts for the hydrogen evolution reaction (HER); however, for the majority of these materials only the edges are active, thereby wasting most of the materials’ surfaces. Recent research has focused on finding new materials with active basal planes. Herein, for the first time, we demonstrate that the hexagonal vdW Fe3GeTe2 (FGT), also a spintronic candidate material, shows both basal plane and edge site HER activities. Partial exfoliation of bulk FGT through sonication increases both basal plane and edge sites leading to significantly improved overpotential. A subsequent compacting of the sample (using plasma sintering at room temperature) to produce a densified electrode leads to an impressive overpotential to drive a current density of 10 mA/cm2 of −0.105 V. DFT free energy calculations not only showed that the high activity is due to the abundant active sites present on the hexagonal Te layer in FGT but also presented an even more HER active layer (106) containing both iron and tellurium active sites. Furthermore, the presence of a thin oxide layer on top of the active FGT layers, as found by XPS, suggests that the real active surface is likely a hybrid FGT/oxide layer. These results demonstrate the high basal plane and edge sites HER activity of FGT, thus opening a new avenue for the design and screening of related iron-based vdW materials, their composites, and their surface functionalization as high-performing electrocatalysts.