Stiffening the Pb-X Framework through a π-Conjugated Small-Molecule Cross-Linker for High-Performance Inorganic CsPbI2Br Perovskite Solar Cells

Li，Hui1; Hao，Xiaotao2; Chang，Bohong1; Li，Zihao1; Wang，Lian1; Pan，Lu1; Chen，Xihan3; Yin，Longwei1

2021

10.1021/acsami.1c06533

ACS Applied Materials & Interfaces   影响因子和分区

1944-8244

1944-8252

Inorganic CsPbI2Br perovskites have witnessed incredible advances as a promising representative for translucent and tandem solar cells, but unfortunately, they are still plagued by serious energy losses and undesired phase instability. Herein, a new type of π-conjugated small molecule of 4-guanidinobenzoic-acid-hydrochloride (4-GBACl) is demonstrated to effectively cross-link the Pb-X framework of perovskites. The strong coordination between 4-GBACl and the [PbX6]4- octahedron of perovskites effectively stiffens the Pb-X framework to suppress the ion migration, thus stabilizing the perovskite phase structure against light and thermal conditions. Apart from the physical barrier for phase instability resulting from the hydrophobic benzene ring at grain boundaries (GBs), guanidinium cations and-COOH and Cl- groups can simultaneously afford the passivation of positively and negatively charged defects at the GBs and surface, including undercoordinated halide species and undercoordinated Pb2+ ions, thereby effectively inhibiting the charge trapping/recombination centers. Two-dimensional confocal-fluorescence mapping images provide a visualized sight into the significantly suppressed nonradiative recombination and the prolonged carrier lifetime. It is suggested that the 4-GBACl additive plays multiple roles in grain cross-linking to regulate crystallization, distinctly reducing the trap-state density, ion migration inhibition, and moisture barrier in CsPbI2Br films. Consequently, the 4-GBACl-treated device exhibits a champion power conversion efficiency (PCE) of 15.59% accompanied with a considerably improved Voc of 1.28 V and maintains 88% of the initial PCE value after 1200 h aging under 20% relative humidity.

charge trapping CsPbI2Br defect passivation stability [PbX6]4-octahedron

SCI ; EI

英语

其他

State Key Program of the National Natural Science of China[U1906227] ; National Natural Science Foundation of China[51872171] ; Key Program of Natural Science Foundation of Shandong Province[ZR201801290005]

Science & Technology - Other Topics ; Materials Science

Nanoscience & Nanotechnology ; Materials Science, Multidisciplinary

WOS:000693050200027

AMER CHEMICAL SOC

20213610856234

Bromine compounds ; Cesium compounds ; Charge trapping ; Chlorine compounds ; Conversion efficiency ; Energy dissipation ; Grain boundaries ; Ions ; Lead compounds ; Molecules ; Perovskite ; Perovskite solar cells

Minerals:482.2 ; Energy Losses (industrial and residential):525.4 ; Energy Conversion Issues:525.5 ; Atomic and Molecular Physics:931.3

2-s2.0-85114092699

Scopus

1.Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials,Ministry of Education,School of Materials Science and Engineering,Shandong University,Jinan,250061,China
2.State Key Laboratory of Crystal Materials,School of Physics,Shandong University,Jinan,250100,China
3.Department of Mechanical and Energy Engineering,Southern University of Science and Technology,Shenzhen,518055,China

Li，Hui,Hao，Xiaotao,Chang，Bohong,et al. Stiffening the Pb-X Framework through a Ï€-Conjugated Small-Molecule Cross-Linker for High-Performance Inorganic CsPbI2Br Perovskite Solar Cells[J]. ACS Applied Materials & Interfaces,2021,13(34):40489-40501.

Li，Hui.,Hao，Xiaotao.,Chang，Bohong.,Li，Zihao.,Wang，Lian.,...&Yin，Longwei.(2021).Stiffening the Pb-X Framework through a Ï€-Conjugated Small-Molecule Cross-Linker for High-Performance Inorganic CsPbI2Br Perovskite Solar Cells.ACS Applied Materials & Interfaces,13(34),40489-40501.

Li，Hui,et al."Stiffening the Pb-X Framework through a Ï€-Conjugated Small-Molecule Cross-Linker for High-Performance Inorganic CsPbI2Br Perovskite Solar Cells".ACS Applied Materials & Interfaces 13.34(2021):40489-40501.