Pore formation in MoS2 monolayer under irradiation by swift heavy ions: A molecular dynamics study

Abstract

Molecular dynamics simulations were performed to study the formation process of nanopores in a freestanding MoS2 monolayer irradiated using swift heavy ions. We considered five types of ions (Ar, Kr, Xe, W, and Bi) with energies ranging from 26 MeV to 4.5 GeV. The impact point was always located in the center of the cell far from the border to reduce undesired high energy interactions over the periodic boundaries. The two-temperature atomistic model with an explicit account of electron thermal conductivity was used. The possibility of forming pores of various shapes with sizes from 1.5 to 48 nm was found. Pore size increases with ion incident energy and decreases with ion mass. Most of the pores have internal amorphization, which can disappear with increasing the irradiation dose. Our results demonstrate that it is feasible to fabricate controlled nanopores in an MoS2 monolayer via swift heavy ion irradiation with Bi ions being the most efficient. Possible practical applications of the obtained results are discussed.