The emergence of two-dimensional semiconductors (2DSCs) provides a rich material foundation for the construction of new optoelectronic devices1,2. Transition metal dichalcogenides (TMDs), as a representative, has been widely used in the construction of electrically tunable light emitting diodes (LEDs)3, gate-controlled p-n junction diodes4, and solar cells5. However, due to atomically thin geometry of monolayer TMDs, effectively tuning charge doping type and improving light absorption efficien...