基于易升华添加剂辅助合成纯相富铯(CH(NH_(2))_(2))_(x)Cs_(1−x)PbI_(3) 钙钛矿  

Synthesis of Cs-Rich (CH(NH_(2))_(2))xCs_(1−x)PbI_(3) Perovskite Films Using Additives with Low Sublimation Temperature

作　　者：吕培梁 高彩芸 孙秀红 孙明亮[1] 邵志鹏 逄淑平[2] Peiliang Lü;Caiyun Gao;Xiuhong Sun;Mingliang Sun;Zhipeng Shao;Shuping Pang(School of Materials Science and Engineering,Ocean University of China,Qingdao 266100,Shandong Province,China;Qingdao Institute of Bioenergy and Bioprocess Technology,Chinese Academy of Sciences,Qingdao 266101,Shandong Province,China)

机构地区：[1]中国海洋大学材料科学与工程学院,山东青岛266100 [2]中国科学院青岛生物能源与过程研究所,山东青岛266101

出　　处：《物理化学学报》2021年第4期176-182,共7页Acta Physico-Chimica Sinica

基　　金：泰山青年学者(tsqn201812110);国家自然科学基金(51822209,51902324)资助项目。

摘　　要：钙钛矿材料化学组分是决定钙钛矿太阳能电池效率和稳定性的关键,纯无机钙钛矿CsPbI_(3)具有相对较好的热稳定性和光稳定性,但由于Cs^(+)具有较小的离子半径而导致无机钙钛矿相不稳定。最近研究发现富铯FA_(x)Cs_(1−x)PbI_(3)钙钛矿具有相对稳定的相结构,且可以很大程度上保持无机钙钛矿材料的热稳定性和光照稳定性,是一种非常具有前景的钙钛矿材料体系。目前这种富铯的FA_(x)Cs_(1−x)PbI_(3)材料合成是通过引入过量有机组分FAI实现的,其中FAI一方面充当钙钛矿的掺杂剂,另一方面过量的FAI充当添加剂。由于其具有较高的升华温度,后续需要较高的温度使过量的FAI升华,实际上这在实验上很难实现对FAI升华量的精确控制。本文重点研究具有低升华温度的胺类,如碘甲胺(MAI)、碘化二甲胺(DMAI)、碘化乙胺(EAI)、碘化胺(NH_(4)I)和醋酸甲脒(FAAC),作为添加剂制备富铯FA_(x)Cs_(1−x)PbI_(3)钙钛矿材料体系的可行性,这一方面可以有效降低钙钛矿薄膜的热处理温度;另一方面可拓宽的制备纯相钙钛矿成分的窗口期,这对大面积制备纯相富铯FA_(x)Cs_(1−x)PbI_(3)钙钛矿薄膜尤为重要。结果表明MAI和DMAI可以作为合成FA_(x)Cs_(1−x)PbI_(3)钙钛矿材料的有效添加剂,其与PbI2间较强的作用力可以促进Cs_(4)PbI_(6)的形成并有效抑制δ-CsPbI_(3)副产物的生成。合适的升华温度可以使薄膜在保持钙钛矿相结构的同时在较低温度升华去除过量的添加剂,最终实现在相对温和的条件下制备纯相富铯FA_(x)Cs_(1−x)PbI_(3)钙钛矿材料。Chemical components of perovskite layers play a key role in improving the efficiency and stability of perovskite solar cells.Pure inorganic perovskites exhibit good thermal and light stabilities;however,the smaller radius of Cs^(+)leads to a poor perovskite phase stability.In this case,the Cs-rich(CH(NH_(2))_(2))xCs_(1−x)PbI_(3)(CH(NH2)2^(+)=FA^(+))perovskite seems more promising because it simultaneously offers the abovementioned properties,while not forming an unstable perovskite phase.Thus far,the synthesis of Cs-rich FA_(x)Cs_(1−x)PbI_(3) perovskite has been realized by introducing excess formamidinium iodide(FAI)as an additive.However,FAI sublimates at a high temperature and excessive FAI sublimation necessitates even greater temperatures.Therefore,it is difficult to precisely control the ratio of the sublimated FAI from the perovskite film.Herein,the precise synthesis of Cs-rich FA_(x)Cs_(1−x)PbI_(3) perovskites at relatively low sublimation temperatures using amine additives,such as methylammonium iodide(MAI),dimethylamine iodide(DMAI),ethylamine iodide(EAI),ammonium iodide(NH_(4)I),and formamidine acetate(FAAC),was studied.The reaction temperature was reduced when utilizing these additives.Moreover,the window period for the preparation has been widened,which is particularly important for the preparation of pure phase Cs-rich FA_(x)Cs_(1−x)PbI_(3) perovskite films for large devices.In the experiment,perovskite FA_(0.15)Cs_(0.85)PbI_(3) was selected because of its good stability.The reaction process of the additive that assisted perovskite preparation was studied.Firstly,0.85 mmol of MAI,DMAI,EAI,FAAC,and NH_(4)I each were added to 1 mmol of FA_(0.15)Cs_(0.85)PbI_(3) solution.Then,the precursor solution was spin-coated and thermally annealed.The FA_(0.15)Cs_(0.85)PbI_(3) films were formed by sublimation of the additives during thermal annealing.The influence of different additives on the film formation process was traced using X-ray diffraction(XRD)measurements and UV-visible absorbance spectra(UV-V

关 键 词：无机卤化物钙钛矿 甲脒 掺杂 添加剂 太阳能电池 

分 类 号：O646[理学—物理化学]