Time: 14:30-16:00, Friday, August 5, 2022

Venue: Room 611, 6F, Building 2, Yunqi Campus

Host: Dr. Rui Wang, Assistant Professor, School of Engineering, Westlake University

Speaker：

Prof. Dawei Di

Professor

College of Optical Science and Engineering

Zhejiang University

Biography:

Dawei Di is a professor at Zhejiang University. He received B.Eng. and Ph.D. (in Engineering) from the University of New South Wales (2004-2012), and a second Ph.D. (in Physics) from the Cavendish Laboratory, University of Cambridge (2012-2017). He continued his work as a postdoctoral researcher in the same laboratory at Cambridge (2017-2018) before joining Zhejiang University in 2018. Dawei Di’s research interests include the physics and application of novel optoelectronic devices, with a current focus on organic and perovskite light-emitting diodes. As corresponding or first author, he published their findings in leading journals including Science, Nature Photonics (cover article), Nature Electronics (cover article), Nature Communications and Joule. Dawei Di was an honouree of MIT Technology Review Innovators Under 35 (global, 2019); his research is supported by the Kun-Peng Programme of Zhejiang Province (2020).

Abstract:

As a candidate of next-generation light sources, perovskite LEDs rapidly exceeded the 20% external quantum efficiency (EQE) milestone. For example, we showed in our work that with careful device design, it was possible to achieve near-unity internal quantum efficiencies (IQEs), demonstrating the potential of perovskite semiconductors for extremely efficient electroluminescence. In this presentation, we discuss some design considerations behind the high IQEs, and for achieving EQEs that approach the theoretical limits. We discuss the lessons learned from our former studies in high-efficiency OLEDs, and the important role of charge-transport interfaces in the realisation of this goal. Transient optical spectroscopy experiments are carried out to illustrate how radiative and non-radiative processes play their roles in the high-performance devices. Finally, our recent efforts in addressing the grand challenges of perovskite LEDs, including device operational instability, are presented.

Contact:

Ms. Huaiwei Shi, School of Engineering

shihuaiwei@westlake.edu.cn