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Controlling the Dirac point voltage of graphene is essential for realizing various practical applications of graphene. Here, control of the doping state is achieved in flexible graphene field effect transistors (GFETs) by applying mechanical bending stress. By gradually increasing the bending strain (the decrease of upward/downward bending radius), the Dirac point ( V Dirac ) linearly shifts to left/right, which is induced by the flexoelectric effect of the ferroelectric Pb 0.92 La 0.08 Zr 0.52 Ti 0.48 O 3 (PLZT) gate. In addition, a superior mechanical antifatigue character is obtained in the flexible GFETs, and the doping effect is recoverable. The sensitivity to strain and high bending stability not only offer an easy, controllable and nonintrusive method to obtain a specific doping level in graphene for flexible electric devices, but also highlight the enormous potential of the flexible ferroelectric PLZT-gated GFETs as wearable sensors. 

Abstract Lateral p–n junctions take the unique advantages of 2D materials, such as graphene, to enable single‐atomic layer microelectronics. A major challenge in fabrication of the lateral p–n junctions is in the control of electronic properties on a 2D atomic sheet with nanometer precision. Herein, a facile approach that employs decoration of molecular anions of bis‐(trifluoromethylsulfonyl)‐imide (TFSI) to generate p‐doping on the otherwise n‐doped graphene by positively polarized surface electric dipoles (pointing toward the surface) formed on the surface oxygen‐deficient layer “intrinsic” to an oxide ferroelectric back gate is reported. The characteristic double conductance minimaV_Dirac−andV_Dirac+illustrated in the obtained lateral graphene p–n junctions can be tuned in the range of −1 to 0 V and 0 to +1 V, respectively, by controlling the TFSI anions and surface dipoles quantitatively. The unique advantage of this approach is in adoption of polarity‐controlled molecular ion attachment on graphene, which could be further developed for various lateral electronics on 2D materials.