Strain-mediated oxygen evolution reaction on magnetic two-dimensional monolayers

By screening 56 magnetic 2D monolayers through first-principles calculations, it was found that 8 magnetic 2D monolayers (CoO2, FeO2, FeSe, FeTe, VS2, VSe2, VTe2 and CrSe2) can bind O*, OH* and OOH* intermediates of the oxygen evolution reaction (OER), in which the overpotentials of CoO2, FeO2, VSe2, and VTe2 monolayers are 0.684, 1.107, 0.863 and 0.837 V, respectively. After applying suitable biaxial tensile strains, the overpotentials of CoO2, FeO2 and VTe2 monolayers are reduced over 40%. In particular, the overpotentials of CoO2 and VTe2 monolayers decrease to 0.372 V and 0.491 V under the biaxial tensile strains of 4.0% and 3.0%, respectively, which are comparable to the reported overpotentials of noble metal and low-dimensional materials. Tensile strains modify the potential determining step for the OER and enhance the catalytic activity of metal atoms of magnetic 2D monolayers. Magnetic 2D monolayers could be activated by strain engineering as catalysts for the OER.