High-efficiency, very-high color rendering white organic light-emitting diode with a high triplet interlayer

Abstract

This study reports the fabrication of a highly efficient, very high color-rendering index (CRI) white organic light-emitting diode (OLED) using five organic dyes doped into two different phosphorescent and fluorescent emissive layers separated by a high tripletenergy interlayer. The resulting white OLED achieves a 93 CRI with a power efficiency of 23.3 lm W À1 at 100 cd m À2 , or 14.3 lm W À1 at 1000 cd m À2 . This high CRI is attributable to the five dyes employed in this design, which together emit a relatively wide spectrum that nearly covers the entire range of visible light. At the proper thickness, the interlayer enables the device to balance the distribution of carriers in the two emissive zones and achieve a maximum power efficiency while maintaining high CRI.

Disruptive characteristics and lifetime issues of OLEDs

“…Device I: without an interlayer, Device II: with an interlayer of 1.5/3.0/4.5/6.0 nm, and Device III: with the electron transporting layer of Alq3 replaced by TPBi. 50 and phosphorescent emissive layers separated by a high triplet-energy interlayer as shown in Fig. 14.8(b) .…”

“…The resulting device achieved a high power effi ciency of 23.3 lm/W at 100 cd m −2 , or 14.3 lm/W at 1000 cd m −2 with a very-high CRI of 93. 50 …”

Enabling a bright orange–red emission with a high EQE with a seven-member-ring based fluorescent emitter with a matching host

“…Organic light-emitting diodes (OLEDs) are of tremendous interests because of their great potential in high-quality flat-panel displays and solid-state lighting applications [1][2][3][4][5]. To reach more energy-saving and hence have a long lasting device lifetime, devising OLEDs with a higher power efficiency is always demanded before reaching their theoretical efficiency limits.…”

Enabling high-efficiency organic light-emitting diodes with a cross-linkable electron confining hole transporting material

“…Hole transporting material 27 VPEC 28 Triplet-energy 29 Hole mobility 30 Electron confining function 31 Efficiency 32 Solution process 33 OLEDs 34 3 5 a b s t r a c t 36 Wet-process enables flexible, large area-size organic devices to be fabricated cost-effectively via 37 roll-to-roll manufacturing. However, wet-processed devices often show comparatively poor performance 38 due to the lack of solution-process feasible functional materials that exhibit robust mechanical proper- 39 ties.…”

“…66 Over the past years, numerous efficiency effective architectural 67 approaches have been proposed. They include the employment 68 of low interfacial resistance P-I-N structures [14-18], low 69 carrier-injection-barriers [19][20][21][22], balanced carrier injection 70 [23-28], carrier and exciton confinement [29][30][31][32][33], stepwise emis- 71 sive layers [34], carrier modulation layers [35][36][37], structures 72 enabling exciton to generate on host or on both host and guest 73 [38], structures facilitating host-to-guest energy transfer [39,40], 74 and co-host structures [41,42], etc. All these approaches are valid 75 for OLED devices fabricated via dry-process, but not all applicable 76 if via wet-process.…”