“…After atomic deuterium exposure, for any value of V h , V CNP had shifted to more negative values. This n-doping of graphene is attributed to deuterium adsorption, hydrogen being an electron donor for graphene. − The magnitude of the V CNP shift depends on V h . The V CNP shift was found to be −20, −8, −1, and −1.5 V for V h = −30, −20, 0, and +30 V, respectively.…”