▎ 摘　　要

Effective control of hydrogenation of graphene is of great scientific and technological importance. However, the reversible control of H density (n(H) ) on graphene is difficult due to the irreversible H-2 formation of the detached H adatoms. Here we present a novel mechanism for controlling n(H) by using the unique proton transfer reaction between NH3 gas and hydrogenated graphene, which can be tuned by applying perpendicular electric fields. Using first-principles calculations, we show that n(H) can be reversibly tuned by the applied electric fields around the critical density for the Anderson localization in hydrogenated graphene. The proposed field-induced control of H adsorption or desorption on graphene opens a path toward the development of new graphene transistors based on the tunable degree of disorder.