期刊
ACS NANO
卷 14, 期 5, 页码 6076-6086出版社
AMER CHEMICAL SOC
DOI: 10.1021/acsnano.0c01817
关键词
perovskite light emitting diodes; efficiency roll-off; ultrahigh brightness; high injection current density; charge injection balance; Auger recombination; Joule heat
类别
资金
- National Science Foundation [ECCS-1807397, NNCI-1542101, ECC-1542101]
- IP Group plc
- University of Washington
- Molecular Engineering & Sciences Institute
- Clean Energy Institute
- National Institutes of Health
Perovskite light-emitting diodes (PeLEDs) have undergone rapid development in the last several years with external quantum efficiencies (EQEs) reaching over 21%. However, most PeLEDs still suffer from severe efficiency roll-off (droop) at high injection current densities, thus limiting their achievable brightness and presenting a challenge to their use in laser diode applications. In this work, we show that the roll-off characteristics of PeLEDs are affected by a combination of charge injection imbalance, nonradiative Auger recombination, and Joule heating. To realize ultrabright and efficient PeLEDs, several strategies have been applied. First, we designed an energy ladder to balance the electron and hole transport. Second, we optimized perovskite materials to possess reduced Auger recombination rates and improved carrier mobility. Third, we replaced glass substrates with sapphire substrates to better dissipate joule heat. Finally, by applying a current-focusing architecture, we achieved PeLEDs with a record luminance of 7.6 Mcd/m(2). The devices can be operated at very high current densities (J) up to similar to 1 kA/cm(2). Our work suggests a broad application prospect of perovskite materials for high-brightness LEDs and ultimately a potential for solution-processed electrically pumped laser diodes.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据