Transition metal dichalcogenides (TMDs) are potential candidates towards the next-generation photodetector, owing to their tunable energy bandgap and strong light–matter interaction. However, the low charge-carrier mobility and insufficient quantum efficiency of TMDs-based devices restrain their optoelectronic performances. Therefore, an effective and facile doping method needs to be developed for overcoming their poor optoelectronics properties. Here, we demonstrate a controllable nondegenerate n-doping technique for 2D TMDs materials by annealing under NH₃ flow. The on/off current ratio and field-effect mobility of the device after annealing treatment increases about 2 orders of magnitude and 23 times, respectively. We attribute this remarkable doping effect to the physical adsorption and chemical adsorption of NH₃ as well as the associated formation of isolated sulfur vacancies, which is dynamically activated during the annealing treatment, and further verified by the atomic-scale characterization and density functional theory calculations. The annealing temperature and time present a controllable modulation on the electron doping levels of the WS₂ channel. The fabricated WS₂ photodetector can operate in a broad range of visible light at room temperature. At 532 nm wavelength, the responsivity of 2.97 A/W, external quantum efficiency of 699% and specific detectivity of over 10¹⁰ Jones indicate its great potential in sensitive and power-efficient photodetectors. Our results provide an effective method to realize controllable n-doping of 2D materials, aiming for fabricating high-performance 2D photodetectors.

过渡金属二硫化物 (TMD) 是下一代光电探测器的潜在候选者，因为它们具有可调的能带隙和强光-物质相互作用。然而，基于 TMD 的器件的载流子迁移率低和量子效率不足限制了它们的光电性能。因此，需要开发一种有效且简便的掺杂方法来克服其较差的光电性能。_{在这里，我们通过在 NH 3}下退火来展示二维 TMD 材料的可控非退化 n 掺杂技术流动。退火处理后器件的开/关电流比和场效应迁移率分别提高了约2个数量级和23倍。_{我们将这种显着的掺杂效应归因于NH 3}的物理吸附和化学吸附以及相关的孤立硫空位的形成，这些空位在退火处理过程中被动态激活，并通过原子尺度表征和密度泛函理论计算进一步验证. _{退火温度和时间对WS 2}通道的电子掺杂水平呈现可控调制。制造的 WS ₂光电探测器可以在室温下在广泛的可见光范围内工作。在532 nm波长下，其响应度为2.97 A/W，外量子效率为699%，比探测率超过10 10^琼斯，表明其在灵敏和节能光电探测器方面具有巨大潜力。我们的研究结果为实现二维材料的可控 n 掺杂提供了一种有效的方法，旨在制造高性能的二维光电探测器。