A review on n-type chemical doping of graphene films: preparation, characterization and applications

and post-treatment doping using various dopants, namely nitrogen, phosphorus, sulfur, metals, and molecular species. Subsequently, the influence of precursor chemistry, chemical vapor deposition (CVD) parameters, and interface engineering on doping efficiency and stability is highlighted. In parallel, advanced characterization techniques are surveyed, with emphasis on their capability to probe bonding configuration, electronic structure, and local dopant distribution. Finally, potential applications of n-doped graphene films in high-performance field-effect transistors, transparent electrodes, and flexible sensors are outlined. The review also discusses current challenges and perspectives on future research directions, including atomically precise doping control, multi-modal characterization, and the exploration of synergistic doping strategies for scalable and stable device integration.