Grain size dependence of penetration depth of hydrogen injection into polycrystalline graphite by molecular simulation

Abstract

Many different carbon materials are developed for diverse applications for industrial and scientific uses. It is known that the amount of hydrogen retained in carbon materials under plasma irradiation strongly depends on the structural characteristics of the material, such as grain size. To clarify the cause of the difference in the amount of hydrogen retained in different carbon materials, hydrogen atom injection into polycrystalline graphite is investigated on the atomic scale by a hybrid simulation technique consisting of binary-collision-approximation-based simulation and molecular dynamics simulation. Then, the incident energy and grain size dependences of the penetration profile of incident hydrogen atoms are carefully investigated.