III–V semiconductor nanowires are indispensable building blocks for nanoscale electronic and optoelectronic devices. However, solely relying on their intrinsic physical and material properties sometimes limits device functionalities to meet the increasing demands in versatile and complex electronic world. By leveraging the distinctive nature of the one-dimensional geometry and large surface-to-volume ratio of the nanowires, new properties can be attained through monolithic integration of conventional nanowires with other easy-synthesized functional materials. Herein, we combine high-crystal-quality III-nitride nanowires with amorphous molybdenum sulfides (a-MoS_x) to construct III-nitride/a-MoS_x core-shell nanostructures. Upon light illumination, such nanostructures exhibit striking spectrally distinctive photodetection characteristic in photoelectrochemical environment, demonstrating a negative photoresponsivity of −100.42 mA W⁻¹ under 254 nm illumination, and a positive photoresponsivity of 29.5 mA W⁻¹ under 365 nm illumination. Density functional theory calculations reveal that the successful surface modification of the nanowires via a-MoS_x decoration accelerates the reaction process at the electrolyte/nanowire interface, leading to the generation of opposite photocurrent signals under different photon illumination. Most importantly, such polarity-switchable photoconductivity can be further tuned for multiple wavelength bands photodetection by simply adjusting the surrounding environment and/or tailoring the nanowire composition, showing great promise to build light-wavelength controllable sensing devices in the future.

III-V 半导体纳米线是纳米级电子和光电器件不可或缺的组成部分。然而，仅仅依靠它们固有的物理和材料特性有时会限制设备的功能，以满足多功能和复杂电子世界日益增长的需求。通过利用纳米线的一维几何形状和大的表面积与体积比的独特性质，可以通过将传统纳米线与其他易于合成的功能材料进行单片集成来获得新的特性。在此，我们将高晶体质量的 III 族氮化物纳米线与非晶硫化钼 (a-MoS _x ) 结合起来构建 III 族氮化物/a-MoS _x核壳纳米结构。在光照下，这种纳米结构在光电化学环境中表现出惊人的光谱独特的光电检测特性，在 254 nm 光照下表现出 -100.42 mA W ^-1的负光响应性，在 365 nm 光照下表现出 29.5 mA W ^{-1的正光响应性。}密度泛函理论计算表明，通过 a-MoS _{x成功地对纳米线进行表面改性}装饰加速了电解质/纳米线界面的反应过程，导致在不同光子照射下产生相反的光电流信号。最重要的是，通过简单地调整周围环境和/或定制纳米线成分，这种极性可切换的光电导率可以进一步调整用于多波段光电探测，显示出在未来构建光波长可控传感装置的巨大希望。