Title: Nanostructured Metal Halide Perovskite Materials for Emerging Optoelectronics
Time: 2022-06-23 15:00
Venue: Institute for Energy Research, 1517
Organizer: Institute for Energy Research
Abstract: Metal halide perovskite materials are regarded as highly promising materials for high performance optoelectronics due to excellent optical absorption, long carrier diffusion length, tunable composition, etc., thus have triggered broad attention for applications including solar cells, photodetectors and light-emitting diodes. Conventionally, solution processes have been utilized to fabricate perovskite materials. In our work, in order to achieve high material quality and device scalability, we have developed chemical vapor deposition process to grow ordered high density perovskite nanowire (NW) and quantum wire (QW) arrays in nanoengineering templates with materials including MAPbX3, FAPbX3 CsPbX3 (X=I, Br, Cl). The geometrical factors of NWs/QWs, namely, periodicity, diameter and length can be precisely nanoengineered. Intriguingly, we have discovered that the chemically and mechanically robust template can effectively protect perovskite NWs against water and oxygen invasion thus the material chemical stability and phase stability are significantly better than planar perovskite films. To explore device applications of perovskite NW arrays, they have been fabricated into novel optoelectronic devices such as photodetectors and bionic eye. Meanwhile, we have also fabricated high efficiency and large-scale NW/QW LEDs on self-organized nanophotonic templates and achieved much improved external quantum efficiency (EQE) as compared to planar control device. These results will be demonstrated in this presentation. And they suggest that in addition to material optimization, device structure innovation, particularly utilization of various types of nanostructures can lead to high performance optoelectronics.
