Transition metal dichalcogenides (TMDCs) and two-dimensional organic and inorganic hybrid lead halide perovskites (2DPVSKs) have emerged as highly promising materials for ultralight and ultrathin optoelectronics application. They both exhibit tunability of electronic properties such as band structure, and they can form heterostructures with various types of two-dimensional materials for novel physical properties not observed in single components. However, TMDCs exhibit poor emission efficiency due to defect states and direct-to-indirect interband transition, and 2DPVSKs suffer from poor stability in ambient atmosphere. Here we report that fabrication of TMDC-on-2DPVSK heterostructures using a solvent-free process leads to novel optical transitions unique to the heterostructure which arise from the hybrid interface and exhibit a strong photoluminescence. Moreover, a two orders of magnitude enhancement of the photoluminescence as compared to WS2 emission is observed. The TMDC on top of 2DPVSK also significantly improves the stability as compared to bare 2DPVSK. Enhanced emission can be explained by electronic structure modification of TMDC by novel interfacial interactions between TMDC and 2DPVSK materials, which shows promise of the heterostructure for high efficiency and stable optoelectronic devices.
Bibliographical noteFunding Information:
This work is part of the “Photonics at Thermodynamic Limits” Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0019140. We also acknowledge Northrop Grumman for financial support of instrumentation. A.Y. and J.W. acknowledge financial support from a Resnick Institute Fellowship. A.D.M. and J.-C.B. acknowledge support by the DOE-EERE DE-FOA-0001647 program. MGK thanks ONR for support on investigating the stability of 2D perovskites (N00014-17-1-2231). We acknowledge support from the Beckman Institute of the California Institute of Technology to the Molecular Materials Research Center. We are grateful to Prof. George R. Rossman for technical help, discussions, and support. We thank Prof. Jacky Even for useful discussions concerning the perovskite surface termination.
© 2019 American Chemical Society.
- Two dimensional materials
- transition metal dichalcogenide