CsPbBr3 QDs Modified Vertically Layered MoS2/Si Heterojunction for Fast UV-vis-NIR Spectrum Flexible Photodetectors

The CsPbBr3 quantum dots (QDs) modified vertically layered MoS2/Si (V-MoS2/Si) heterojunction is successfully prepared. It is found that the resulting photodetector realizes the UV-vis-NIR broad-spectrum detection with good sensitivity and fast photoresponse speed. Typically, the responsivity and response/recovery time towards 808 nm reach up to 0.975 A W-1 and 6.8/6.7 ms, respectively. Furthermore, it is demonstrated that with the modification of CsPbBr3 QDs, the responsivities of the pure V-MoS2/Si-based photodetector for 532, 671, and 808 nm detection are boosted by 5.43, 2, and 5.45 times, respectively. The enhanced sensing performance is attributed to the vis-NIR light harvesting capability and excellent electrical transporting property of the CsPbBr3 QDs. Most importantly, the flexibility can be applied to the wearable devices for various working environments. The present work pushes the development of the flexible devices for broadband spectrum detection faced to practical application.

Automated summary

This study successfully prepared a CsPbBr3 quantum dots-modified vertically layered MoS2/Si heterojunction photodetector, demonstrating excellent performance in UV-vis-NIR broad-spectrum detection, particularly in terms of response speed and responsivity at 808 nm. The modification of CsPbBr3 QDs significantly enhanced the responsivities of the V-MoS2/Si-based photodetector at 532 nm, 671 nm, and 808 nm wavelengths.