In this paper, the CDFT-AIMD methodology for simulating electron transfer process across an electrode-electrolyte interface was applied. We have studied the kinetics of electron transfer from graphene to a series of redox-active molecules using Marcus theory. This approach allows us to not only assess the transfer rate of electron more realistically, but also gain insights into the chemistry of redox reactions in the aqueous systems. A large electrode and explicit solvent were essential for modeling electrode-electrolyte interface systems and evaluating Marcus parameters in our study.