The device results are shown in FIG. 6J, FIG. 6K, and FIG. 6L with a peak ηEQE=0.3±0.3% and the highest device EQE of 1% (FIG. 6J). The local defects or overlapped edges of the grains caused EQE variation from 1% to 0.01% within the same batch of growth. The local defects and overlapped edges of the grains are shown by the dark area of the device illumination demonstrated with an optical microscope as shown in FIG. 6K, inset. The device showed diode characteristics with high conductivity as the JV curve in FIG. 6K indicates. As shown in FIG. 6L, the emission from the monolayer WS2 had no residual emission from any other organic layers, demonstrating efficient exciton generation at the EML-ETL interface followed by the F?rster transfer into the WS2 active layer.
Experiment #2
Introduction
