Large-Area Organic–Transition Metal Dichalcogenide Hybrid Light-Emitting Device

Abstract

We demonstrate a hybrid light-emitting device (LED) employing a chemical-vapor-deposition grown, centimeter-scale monolayer of WS2 (mWS2) as the active luminescent material embedded within conductive organic layers. The active area of the hybrid LED is composed of mWS2, located within the organic host matrix, sandwiched between the hole- and electron-transporting organic layers. The mWS2 shows fast exciton decay and efficient light outcoupling compared to the organic dyes used for OLEDs, whereas organic layers enable a precisely controlled, large-area fabrication process. As a result, LEDs with an average external quantum efficiency of 0.3 ± 0.3% and with the highest efficiency of 1% were achieved. Also, we show that negatively charged excitons, also known as trions, are generated in the mWS2 with the injected current, causing an efficiency roll-off at high current densities. Our result introduces a means for incorporating a range of emissive inorganic thin films into an organic device structure, thereby taking advantage of the positive attributes of both material systems.

Long-Range Propagation of Exciton-Polaritons in Large-Area 2D Semiconductor Monolayers

“…29,30 Such a small scale presents substantial challenges for practical on-chip TMD-based devices. 31,32 Also, there remains a need to systematically engineer long-range BSWP propagation in TMD monolayers. In contrast to previous work using micrometer-scale TMD flakes, 29,30 here we employ centimeter-scale, metal−organic chemical vapor deposition (MOCVD)-grown monolayers for the BSW-exciton strong coupling and demonstrate BSWP-mediated long-range energy transport at room temperature.…”

“…Recently, a monolayer TMD-based BSW polariton (BSWP) has been demonstrated to yield propagation lengths of several tens of micrometers based on mechanically exfoliated TMDs with a lateral size of only a few square micrometers. , Such a small scale presents substantial challenges for practical on-chip TMD-based devices. , Also, there remains a need to systematically engineer long-range BSWP propagation in TMD monolayers. In contrast to previous work using micrometer-scale TMD flakes, , here we employ centimeter-scale, metal–organic chemical vapor deposition (MOCVD)-grown monolayers for the BSW-exciton strong coupling and demonstrate BSWP-mediated long-range energy transport at room temperature.…”

Bright and Efficient Light‐Emitting Devices Based on 2D Transition Metal Dichalcogenides

“…The LEDs comprising of hybrid heterostructures involving TMDCs and other families of materials have also been reported which can help combine the benefits of different material platforms and allow large-area emission. [387][388][389] The heterostructures of TMDCs can provide opportunities to create devices with superior performance and versatility compared to those made using single TMDCs.…”

Self-powered semitransparent WS2/LaVO3 vertical-heterostructure photodetectors by employing interfacial hexagonal boron nitride

“…Broadband photodetector (PD) applications such as imaging sensors, remote temperature monitoring, and environmental detection are critical components of optoelectronic systems [1][2][3][4][5]. Thanks to the advent of two-dimensional (2D) materials with unique properties including graphene (Gr) and transition metal dichalcogenides (TMDC), versatile optoelectronic devices offering promising potential have quickly established themselves as exciting building blocks [6][7][8][9][10][11]. In particular, 2D materials have been introduced as promising candidates for broadband PD due to their high light absorption and high electron mobility [12][13][14][15][16].…”