Two-dimensional (2D) transition metal dichalcogenides have been extensively studied due to their fascinating physical properties for constructing high-performance photodetectors. However, their relatively low responsivities, current on/off ratios and response speeds have hindered their widespread application. Herein, we fabricated a high-performance photodetector based on few-layer MoTe₂ and CdS_0.42Se_0.58 flake heterojunctions. The photodetector exhibited a high responsivity of 7221 A/W, a large current on/off ratio of 1.73×10⁴, a fast response speed of 90/120 µs, external quantum efficiency (EQE) reaching up to 1.52×10⁶ % and detectivity (D*) reaching up to 1.67×10¹⁵ Jones. The excellent performance of the heterojunction photodetector was analyzed by a photocurrent mapping test and first-principle calculations. Notably, the visible light imaging function was successfully attained on the MoTe₂/CdS_0.42Se_0.58 photodetectors, indicating that the device had practical imaging application prospects. Our findings provide a reference for the design of ultrahigh-performance MoTe₂-based photodetectors.

二维（2D）过渡金属二硫属化物因其在构建高性能光电探测器方面具有令人着迷的物理特性而得到了广泛的研究。然而，它们相对较低的响应度、电流开/关比和响应速度阻碍了它们的广泛应用。在此，我们制造了一种基于少层MoTe ₂和CdS _0.42 Se _0.58片状异质结的高性能光电探测器。该光电探测器表现出7221 A/W的高响应度、1.73×10 ⁴的大电流开/关比、90/120 µs的快速响应速度、高达1.52×10 ⁶ %的外量子效率（EQE）和探测灵敏度（D*）达到1.67×10 ¹⁵ Jones。通过光电流映射测试和第一原理计算分析了异质结光电探测器的优异性能。值得注意的是，在MoTe ₂ /CdS _0.42 Se _0.58光电探测器上成功实现了可见光成像功能，表明该器件具有实际成像应用前景。我们的研究结果为超高性能MoTe ₂光电探测器的设计提供了参考。