Grain Boundary Perfection Enabled by Pyridinic Nitrogen Doped Graphdiyne in Hybrid Perovskite. (19th June 2021)

• Record Type: Journal Article
• Authors: Fan, Wenqiang; Zhang, Suicai; Xu, Chenzhe; Si, Haonan; Xiong, Zhaozhao; Zhao, Yunqi; Ma, Kaikai; Zhang, Zheng; Liao, Qingliang; Kang, Zhuo; Zhang, Yue
• Is Part Of: Advanced functional materials. Volume 31:Number 34(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-06-19
• Subjects: defect passivation -- grain boundary -- graphdiyne -- ion migration -- perovskite solar cells; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202104633
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: The solution processing in hybrid perovskite films inevitably results in the formation of detrimental defects at grain boundaries (GBs) that deteriorate the optoelectronic properties and bring about severe hysteresis as well as operational instability. Here, an effective scenario to alleviate the imperfection issue at perovskite GBs via incorporating pyridinic nitrogen‐doped graphdiyne (N‐GDY) is proposed. Taking full advantage of periodic acetylenic linkages and introduced pyridinic N atoms, the deep‐level trap states like Pb–I antisite defects and under‐coordinated Pb atoms are considerably passivated, thus diminishing the undesired non‐radiative recombination. Additionally, the spatial confinement coupling with electrostatic repulsion effect originated from the intrinsic 2D structure of N‐GDY, has been identified to deal with the halide ion migration behavior. Such contributions are further theoretically evidenced with the charge density delocalization as well as the ion migration energy barrier elevation. The authors unprecedentedly verified the superiorities based on the flexible chemical‐tailorability of atomic crystal GDY materials toward polycrystalline perovskite related energy conversion devices. Abstract : Regarding the bottlenecks of defect density and ion migration at grain boundary within mixed halide perovskites, the profound superiorities brought by pyridinic nitrogen‐doped graphdiyne (N‐GDY) are systematically highlighted. It is proposed that the spatial confinement coupling with the electrostatic repulsion effect, induced by the intrinsic 2D structure of N‐GDY, contributes to the conclusive capability of impeding the halide ion migration.