Simultaneous edge and electronic control of MoS2 nanosheets through Fe doping for an efficient oxygen evolution reaction

Abstract

Electronic regulation and structural engineering at the atomic level of electrocatalysts is of vital importance to a highly efficient oxygen evolution reaction (OER). Here we report Fe-doped MoS₂ (Fe-MoS₂) nanosheets in which the Fe dopant influences the synthesis process to simultaneously tune the edge sites and electronic properties of MoS₂. Impressively, the Fe-MoS₂ nanosheets exhibit greatly improved catalytic activity towards the OER, achieving a current density of 50 mA cm⁻² at 290 mV and satisfactory durability in 1.0 M KOH. Transmission electron microscopy analysis confirms that the Fe-MoS₂ nanosheets undergo an atomic-scale structural evolution from horizontally aligned planes to vertically aligned planes, maximally exposing their edge sites. Density functional theory calculations reveal that the substitution of Fe at the Mo site in MoS₂ has the lowest formation energy, offering a low overpotential of 328 mV for the OER.