Tune the photoresponse of monolayer MoS2 by decorating CsPbBr3 perovskite nanoparticles

Tuning the photoresponse of monolayer MoS2 could extend its potential application in many fields, however, it is still a challenge. In this study, CsPbBr3 nanoparticles were prepared and spin-coated on the surface of monolayer MoS2 to fabricate hybrid CsPbBr3/MoS2 photodetectors. By combing the photoelectrical property of the CsPbBr3, the synergistic effect has been systematically studied from its carrier mobility, photoresponse and detectivity. It was found that nanofilm-coating of CsPbBr3 would impede the photoelectric performance due to the electron-hole recombination facilitated by the defects at the interface of CsPbBr3 and MoS2 films. While the nanoparticles decorating was observed to significantly improve the conductivity of the monolayer MoS2, which also increased the on/off ratio of the MoS2 transistor from 8.2 × 103 to 4.4 × 104, and enhanced the carrier mobility from 0.090 cm2 V−1 s−1 to 0.202 cm2 V−1 s−1, ascribing to a mixed electron recombination-injection process. Furthermore, the CsPbBr3 nanofilm would decrease the responsivity to 136 and 178 A/W under the light wavelength of 400 and 500 nm, respectively, while decorating CsPbBr3 nanoparticles improve the photoresponse to 948 and 883 A/W with the detectivity at the level of 1011 Jones. This work may provide an easy and cost-efficient way to tune the photoresponse of MoS2 photodetectors.