Polyhedral Oligomeric Silsesquioxane Enhances the Brightness of Perovskite Nanocrystal-Based Green Light-Emitting Devices

He Huang; Hong Lin; Stephen V Kershaw; Andrei S Susha; Wallace C H Choy; Andrey L Rogach

doi:10.1021/acs.jpclett.6b02224

Polyhedral Oligomeric Silsesquioxane Enhances the Brightness of Perovskite Nanocrystal-Based Green Light-Emitting Devices

J Phys Chem Lett. 2016 Nov 3;7(21):4398-4404. doi: 10.1021/acs.jpclett.6b02224. Epub 2016 Oct 25.

Authors

He Huang¹, Hong Lin², Stephen V Kershaw¹, Andrei S Susha¹, Wallace C H Choy², Andrey L Rogach¹

Affiliations

¹ Department of Physics and Materials Science and Centre for Functional Photonics (CFP), City University of Hong Kong , Kowloon, Hong Kong, SAR China.
² Department of Electrical and Electronic Engineering, The University of Hong Kong , Pokfulam Road, Hong Kong, SAR China.

PMID: 27774786
DOI: 10.1021/acs.jpclett.6b02224

Abstract

The beneficial role of the insulating material polyhedral oligomeric silsesquioxane (POSS) as a solution additive or an additional hole-blocking layer to enhance the performance of electroluminescent green light-emitting devices (LEDs) based on CsPbBr₃ perovskite nanocrystals is demonstrated. POSS improves the surface coverage and the morphological features of the films deposited either from supernatant or suspension of perovskite nanocrystals. The external quantum efficiency and the luminance efficiency of LEDs with an additional POSS layer reach 0.35% and 1.20 cd/A, respectively, constituting a more than 17-fold enhancement to the reference devices without POSS; the LED peak luminance reaches 2983 cd/m², and the device stability is improved. The POSS acts as a hole-blocking layer between the perovskite nanocrystals and TPBi, keeping both electrons and holes located within the active layer for an efficient recombination.