2025/3/10(一)演講公告

• 
• 

會員評等：  / 0

差佳 

詳細內容

上層分類：系所公告

分類：演講

建立於 2025-03-03, 週一 16:08

最近更新於 2025-03-03, 週一 16:21

發佈於：2025-03-03, 週一 16:20

點擊數：1065

演講者：Dr. Le Yang

演講題目：Triplet-triplet annihilation strategies in photon-upconversion & OLEDs

演講地點：博雅館102室

演講時間：114.3.10 上午10點20分~12點10分

演講摘要：

Triplet-triplet annihilation (TTA) enables efficient and versatile photon-upconversion in organics. The same process also can enhance OLED efficiencies by utilising dark triplets.^1-4 Here, we present progresses on efficient TTA-UC in novel composite systems^5-6:

First, we use a hybrid nanocrystal as triplet-sensitizer, and two different organic upconversion emitters, we observe for the first time, a multi-fold enhancement in the upconversion efficiency in such a composite hybrid system.⁵

Next, solid-state photon-upconversion always suffers from low efficiencies and high threshold excitation power. We showcase a novel composite-sensitizer, inspired by the BHJ donor-acceptor of organic photovoltaics, for TTA-UC devices, leading to highly-efficient solid-state upconversion devices with low excitation power, through a one-step solution method. We also scaled-up this strategy on highly-flexible large-area substrates.⁶

Lastly, we explore overcoming the efficiency bottleneck in simple fluorescent OLEDs. First, in a dual-dopant system, lifting rubrene-derivative-based OLEDs to >20% EQE.^1-2 Secondly, in single-dopant devices, by triplet-fusion mechanism, drawing parallels to TTA-UC, to enhance device efficiency ceiling.^3-4

1. L Yang et al, Joule 2019, 3, 2381–2389.
2. D Di, AS Romanov, L Yang et al Science, 2017, 356, 159–163.
3. L Yang et al. Nanoscale Adv. 2022, 4, 1318-1323.
4. D Di, L Yang et al, Adv. Mater. 2017, 29, 1605987.
5. XW Chua, L Dai, M Anaya, SD Stranks, L Yang et al, ACS Nano 2024, 18, 23, 15229–15238.
6. P Bi, L Yang et al, Nature Communications 2024, 15 (1), 5719.

關於講者：

服務單位：National University of Singapore

職稱：Adjunct Assistant Professor

學經歷：

Dr Le Yang received her PhD from the University of Cambridge, where she and her colleagues discovered a new emission mechanism in a class of then-new materials, leading to a breakthrough and record-efficiency organic LEDs, useful for next-generation display technology. Le is now working in IMRE, on luminescent materials, optoelectronics and biosensors, leading the “PROFESS” Group (Printed Organic Flexible Electronics & Sensors). She is also the Head of Department (Sensors & Flexible Electronics). Her notable work has been published in Science, Nature Materials, Nature Communications, Joule, etc; and her team has produced numerous IPs/patents. Le is active in the ecosystem, eg being Associate Editor of Materials Today Chemistry, Joint-Secretary executive committee of the Materials Research Society-Singapore, chairing several conferences and leading outreach activities.

• < 前一頁
• 下一個 >