The model is very large, both geometrically in terms of the number of atoms, in considering the parameters used in general. So, this will indeed be a very time-consuming and memory-gobbling calculation. It seems reasonably set up, although the use of a 2D "corrugated sheet of gold" is a bit odd. Is it even metallic (probably, perhaps, but still, unusual, so you had better study the electrodes a bit).
Perhaps it would be better to inject from graphene or something that's more likely to actually be used in reality, or why not just let the MoS2 be the electrode by itself, and just consider a gate region of the MoS2 sheet?
