Open AccessUnveiling the Effects of Hydrolysis‐Derived DMAI/DMAPbI x Intermediate Compound on the Performance of CsPbI 3 Solar Cells
Author(s) -
Bian Hui,
Wang Haoran,
Li Zhizai,
Zhou Faguang,
Xu Youkui,
Zhang Hong,
Wang Qian,
Ding Liming,
Liu Shengzhong Frank,
Jin Zhiwen
Publication year - 2020
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.201902868
Subject(s) - hydrolysis , adduct , annealing (glass) , energy conversion efficiency , materials science , chemical engineering , perovskite (structure) , chemistry , crystallography , organic chemistry , optoelectronics , composite material , engineering
Abstract Introducing hydroiodic acid (HI) as a hydrolysis‐derived precursor of the intermediate compounds has become an increasingly important issue for fabricating high quality and stable CsPbI 3 perovskite solar cells (PSCs). However, the materials composition of the intermediate compounds and their effects on the device performance remain unclear. Here, a series of high‐quality intermediate compounds are prepared and it is shown that they consist of DMAI/DMAPbI x . Further characterization of the products show that the main component of this system is still CsPbI 3 . Most of the dimethylammonium (DMA + ) organic component is lost during annealing. Only an ultrasmall amount of DMA + is doped into the CsPbI 3 and its structure is stabilized. Meanwhile, excessive DMA + forms Lewis acid–base adducts and interactions with Pb 2+ on the CsPbI 3 surface. This process passivates the CsPbI 3 film and decreases the recombination rate. Finally, CsPbI 3 film is fabricated with high crystalline, uniform morphology, and excellent stability. Its corresponding PSC exhibits stable property and improved power conversion efficiency (PCE) up to 17.3%.