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Updated: Jun 7, 2025

Facile Synthesis of Colloidal Lead Halide Perovskite Nanoplatelets via Ligand-Assisted Reprecipitation
Published on: October 1, 2019
Targeted elimination of tetravalent-Sn-induced defects for enhanced efficiency and stability in lead-free NIR-II
Xiang Guan1,2, Yuqing Li2, Yuanyuan Meng2
1Institute for Electric Light Sources, Shanghai Engineering Research Center for Artificial Intelligence and Integrated Energy System, School of Information Science and Technology, Fudan University, Shanghai, China.
Abstract:
Eco-friendly Sn-based perovskites show significant potential for high-performance second near-infrared window light-emitting diodes (900 nm - 1700 nm). Nevertheless, achieving efficient and stable Sn-based perovskite second near-infrared window light-emitting diodes remains challenging due to the propensity of Sn2+ to oxidize, resulting in detrimental Sn4+-induced defects and compromised device performance. Here, we present a targeted strategy to eliminate Sn4+-induced defects through moisture-triggered hydrolysis of tin tetrahalide, without degrading Sn2+ in the CsSnI3 film. During the moisture treatment, tin tetrahalide is selectively hydrolyzed to Sn(OH)4, which provides sustained protection. As a result, we successfully fabricate second near-infrared window light-emitting diodes emitting at 945 nm, achieving a performance breakthrough with an external quantum efficiency of 7.6% and an operational lifetime reaching 82.6 h.
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