Photodoping strategies in two-dimensional semiconductors: Mechanisms, characterizations, and emerging applications

The rapid expansion of two-dimensional (2D) van der Waals semiconductors has enabled new possibilities for next-generation electronic and optoelectronic technologies. However, the absence of robust, scalable, and CMOS-compatible doping strategies remains a key bottleneck for their circuit-level integration. Conventional doping techniques, such as ion implantation and substitutional doping, are fundamentally incompatible with atomically thin crystals due to lattice damage, poor dopant activation, and limited spatial precision. In this context, photodoping has emerged as a promising alternative, offering non-invasive, reversible, and highly tunable modulation of carrier density through light–matter interactions without compromising structural integrity. By precisely controlling illumination parameters and employing optical patterning techniques, photodoping offers nanometer-scale spatial resolution and enables programmable modulation of doping polarity and carrier concentration. Moreover, specific mechanisms allow for nonvolatile doping states through long-lived charge trapping effects. This review provides a comprehensive overview of recent advancements in photodoping strategies for 2D materials, encompassing device configurations, physical mechanisms, and state-of-the-art characterization methods. We further highlight emerging applications in multifunctional transistors, photodetectors, memory, neuromorphic, and reconfigurable devices, and discuss the challenges and future prospects of integrating photodoping into large-scale 2D material platforms. (Figure presented.).