Two-dimensional (2D) transition metal dichalcogenides have emerged as a promising material system for optoelectronic applications, but their primary figure of merit, the room-temperature photoluminescence quantum yield (QY), is extremely low.The prototypical 2D material molybdenum disulfide (MoS2) is reported to have a maximum QYof 0.6%, which indicates a considerable defect density. Herewe report on an air-stable, solution-based chemical treatment by an organic superacid, which uniformly enhances the photoluminescence and minority carrier lifetime of MoS2 monolayers by more than two orders of magnitude.The treatment eliminates defect-mediated nonradiative recombination, thus resulting in a finalQYofmore than 95%, with a longest-observed lifetime of 10.8 0.6 nanoseconds. Our ability to obtain optoelectronic monolayers with near-perfect properties opens the door for the development of highly efficient light-emitting diodes, lasers, and solar cells based on 2D materials.
|Original language||English (US)|
|Number of pages||4|
|State||Published - Nov 26 2015|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: We thank F. R. Fischer for in-depth discussions on surface chemistry and A. B. Sachid for analysis of the electrical measurements. M.A., J.X., J.W.A., X.Z., and A.J. were funded by the Director, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division of the U.S. Department of Energy, under contract no. DE-AC02-05Ch11231. A. A., J.N., R. A., S.KC, R.M.W., and K.C. were funded by the Center for Low Energy System Technology (LEAST), one of six centers supported by the STARnet phase of the Focus Research Program (FCRP), a Semiconductor Research Corporation program sponsored by Microelectronics Advanced Research Corporation and Defense Advanced Research Projects Agency. D.K. acknowledges support from Samsung, E.Y. acknowledges support from the NSF Center for Energy Efficient Electronics Science (E3S), J.-H.H. acknowledges support from the baseline fund of KAUST, and M.D. acknowledges support from the U.S. Army Research Lab Director's Strategic Initiative program on interfaces in stacked 2D atomic layers and materials.