Folded MoS2 layers with reduced interlayer coupling
The interlayer coupling between MoS2 planes can be reduced by folding the layers, altering the natural crystalline stacking order. Due to this reduction of the interlayer coupling, folded MoS2 presents some of the optoelectronic properties of single-layer MoS2 such as enhanced photoluminescence and contribution of charged excitons to the photoluminescence yield.
We study molybdenum disulfide (MoS2) structures generated by folding single-layer and bilayer MoS2 flakes. We find that this modified layer stacking leads to a decrease in the interlayer coupling and an enhancement of the photoluminescence emission yield. We additionally find that folded single-layer MoS2 structures show a contribution to photoluminescence spectra of both neutral and charged excitons, which is a characteristic feature of single-layer MoS2 that has not been observed in multilayer MoS2. The results presented here open the door to fabrication of multilayered MoS2 samples with high optical absorption while maintaining the advantageous enhanced photoluminescence emission of single-layer MoS2 by controllably twisting the MoS2 layers.
Tsinghua University Press
Andres Castellanos-Gomez,Herre S. J. van der Zant,Gary A. Steele, Folded MoS2 layers with reduced interlayer coupling. NanoRes.2014, 7(4): 572–578