Near-Unity Emitting, Widely Tailorable, and Stable Exciton Concentrators Built from Doubly Gradient 2D Semiconductor Nanoplatelets

Near-Unity Emitting, Widely Tailorable, and Stable Exciton Concentrators Built from Doubly Gradient 2D Semiconductor Nanoplatelets

ACS Nano

10.1021/acsnano.3c05125

http://dx.doi.org/10.1021/acsnano.3c05125

Xiao Liang, Emek G. Durmusoglu, Maria Lunina, Pedro Ludwig Hernandez-Martinez, Vytautas Valuckas, Fei Yan, Yulia Lekina, Vijay Kumar Sharma, Tingting Yin, Son Tung Ha, Ze Xiang Shen, Handong Sun, Arseniy Kuznetsov, Hilmi Volkan Demir

23 August 2023

Liang, X., Durmusoglu, E. G., Lunina, M., Hernandez-Martinez, P. L., Valuckas, V., Yan, F., Lekina, Y., Sharma, V. K., Yin, T., Ha, S. T., Shen, Z. X., Sun, H., Kuznetsov, A., & Demir, H. V. (2023). Near-Unity Emitting, Widely Tailorable, and Stable Exciton Concentrators Built from Doubly Gradient 2D Semiconductor Nanoplatelets. ACS Nano, 17(20), 19981–19992. https://doi.org/10.1021/acsnano.3c05125

The electrostatic interactions (EI) between electrons and holes within semiconductor nanocrystals (NCs) profoundly impact the performance of their optoelectronic systems. However, achieving a broad range, fine-tuning of the EI strength, especially in quasi-2 dimensional core-shell semiconductor NCs, is a daunting challenge, as the shell growth for high efficiency and stability largely compromises the strength of EI. Herein we propose and demonstrate a novel doubly-gradient (DG) core-shell architecture of semiconductor nanoplatelets (NPLs) for on-demand tailoring of the EI strength by controlling the localized exciton concentration via in-plane architectural modulation, demonstrated by a wide tuning of exciton binding energy. Moreover, these exciton-concentration-engineered DG NPLs also exhibit a near-unity quantum yield, remarkable thermal and photo stability, as well as considerably suppressed self-absorption. As proof-of-concept demonstrations, highly efficient color converters and high-performance LEDs (external quantum efficiency:16.9%, maximum luminance: 43,000 cd/m2) have been achieved based on the DG NPLs. This work thus opens up new avenues for developing high-performance colloidal optoelectronic device applications.

Attribution 4.0 International (CC BY 4.0)

This research / project is supported by the A*STAR - MTC Programatic
Grant Reference no. : M21J9b0085

This research / project is supported by the Ministry of Education - Academic Research Fund Tier 1
Grant Reference no. : MOE-RG62/20

This research / project is supported by the Ministry of Education - Tier 1
Grant Reference no. : MOE-RG57/21

This research / project is supported by the Ministry of Education - Tier 2
Grant Reference no. : MOE-T2EP50220-0020

This research / project is supported by the Ministry of Education - Tier 2
Grant Reference no. : MOE-T2EP50122-0005

This research / project is supported by the National Research Foundation - Competitive Research Programme
Grant Reference no. : NRF-CRP23-2019-0007

This research / project is supported by the Ministry of Education - Tier 1
Grant Reference no. : MOE-RG139/22

https://oar.a-star.edu.sg/communities-collections/articles/19976

1936-086X
1936-0851

Institute of Materials Research and Engineering

https://doi.org/10.1021/acsnano.3c05125