Abstract
Organic A′-site ligand structure plays a crucial role in the crystal growth of 2D perovskites, but the underlying mechanism has not been adequately understood. This problem is tackled by studying the influence of two isomeric A′-site ligands, linear-shaped n-butylammonium (n-BA+) and branched iso-butylammonium (iso-BA+), on 2D perovskites from precursor to device, with a combination of in situ grazing-incidence wide-angle X-ray scattering and density functional theory. It is found that branched iso-BA+, due to the lower aggregation enthalpies, tends to form large-size clusters in the precursor solution, which can act as pre-nucleation sites to expedite the crystallization of vertically oriented 2D perovskites. Furthermore, iso-BA+ is less likely to be incorporated into the MAPbI3 lattice than n-BA+, suppressing the formation of unwanted multi-oriented perovskites. These findings well explain the better device performance of 2D perovskite solar cells based on iso-BA+ and elucidate the fundamental mechanism of ligand structural impact on 2D perovskite crystallization.
Original language | English |
---|---|
Article number | 2206787 |
Number of pages | 11 |
Journal | Small : Nano Micro |
Volume | 19 |
Issue number | 12 |
Early online date | 2 Jan 2023 |
DOIs | |
Publication status | Published - 22 Mar 2023 |
Bibliographical note
Funding Information:Z.Q. and H.X. contributed equally to this work. The authors are grateful for the beam time and technical support provided by the 23A SWAXS beamline at NSRRC, Hsinchu. The authors acknowledge the financial support from the Research Grant Council of Hong Kong (RGC) (General Research Fund No. 14305721), CUHK PIEF and CRIMS Grant (No. 3133288), and CUHK Direct Grant. H.X. acknowledges the funding from the China Scholarship Council (CSC) (Grant No. 201806420038). S.T. acknowledges the funding by the Computational Sciences for Energy Research (CSER) tenure track program of Shell and NWO (Project No. 15CST04‐2) and the NWO START‐UP grant from the Netherlands.
Funding
Z.Q. and H.X. contributed equally to this work. The authors are grateful for the beam time and technical support provided by the 23A SWAXS beamline at NSRRC, Hsinchu. The authors acknowledge the financial support from the Research Grant Council of Hong Kong (RGC) (General Research Fund No. 14305721), CUHK PIEF and CRIMS Grant (No. 3133288), and CUHK Direct Grant. H.X. acknowledges the funding from the China Scholarship Council (CSC) (Grant No. 201806420038). S.T. acknowledges the funding by the Computational Sciences for Energy Research (CSER) tenure track program of Shell and NWO (Project No. 15CST04‐2) and the NWO START‐UP grant from the Netherlands.
Keywords
- 2D perovskites
- clusters
- crystallization process
- density functional theory calculations
- dynamic light scattering
- in situ grazing-incidence wide-angle X-ray scattering
- ligand structures