Probing permeation of energetic hydrogen atoms through molybdenum disulphide on graphene platform

Abstract

Graphene and h-BN are known to be permeating for thermal protons, molybdenum disulphide (MoS2) is found to block them. We report permeation of highly energetic hydrogen atoms produced from electron beam irradiation of hydrogen silsesquioxane resist through MoS2 layers on graphene platform. Single-layer graphene has been used as a detector to estimate permeation. Extent of hydrogenation of graphene, estimated from Raman spectroscopy studies, was used to quantify the permeation of hydrogen atoms through monolayer, tri-layer and bulk MoS2. A decrease in defect density induced in graphene was observed with increasing layer numbers of MoS2. This data was used to estimate the absorption coefficient of MoS2 using the defect density nD , with a value close to 0.06 Å−1. The percentage transmission of hydrogen atoms was found to be 65% per layer.