钙钛矿双功能钝化剂:室温离子液体的机械化学制备  

Perovskite Dual-function Passivator: Room Temperature Ionic Liquid Obtained from Mechanochemical Preparation

作　　者：武文俊 李玉婷 冯茜 丁文星 Wu Wenjun;Li Yuting;Feng Xi;Ding Wenxing(School of Chemical and Molecular Engineering,East China University of Science and Technology,Shanghai 200237;School of Chemical Engineering,East China University of Science and Technology,Shanghai 200237;School of Material Science and Engineering,East China University of Science and Technology,Shanghai 200237;School of Pharmacy,East China University of Science and Technology,Shanghai 200237)

机构地区：[1]华东理工大学化学与分子工程学院,上海200237 [2]华东理工大学化工学院,上海200237 [3]华东理工大学材料科学与工程学院,上海200237 [4]华东理工大学药学院,上海200237

出　　处：《化学学报》2022年第11期1469-1475,共7页Acta Chimica Sinica

基　　金：国家自然科学基金(No.22075083)资助

摘　　要：室温离子液体本身作为绿色溶剂的同时,其绿色合成也面临着新的挑战.机械化学又以其无溶剂、无须高温和高压等绿色过程为优势而逐渐发展成为新的学科.本工作重点关注室温离子液体1-甲基-3-苄基-咪唑碘的绿色合成与应用,利用机械化学合成法,直接将碘代苯甲烷和N-甲基咪唑置于行星球磨机中球磨得到产物,将产物应用于可印刷介观钙钛矿太阳能电池的晶体缺陷能级的钝化.经用量优化后,器件的短路电流密度(J_(SC))、填充因子(FF)和光电转换效率(PCE)分别从16.19 mA·cm^(-2)、68.04%和10.00%提高至17.59 mA·cm^(-2)、71.89%和11.47%.这可归因于咪唑环上氮原子孤对电子对钙钛矿晶体表面未配位Pb^(2+)的电荷具有分散作用以及苯环大π键电子云与I-间的静电作用对I-迁移具有抑制作用,进而约束了Pb^(2+)和碘空位对激发态电子的捕获,因此大幅提升了器件的短路电流密度(J_(SC)),为高性能新型钝化剂的制备开辟了新的路径.Although room temperature ionic liquids(RTILs)themselves are green solvents,their green synthesis faces great challenges actually.Mechanochemistry is developing as a new discipline with the advantages of solvent-free,green processes without high temperature and pressure.In this work,we obtained 1-methyl-3-benzyl-imidazolium iodide by directly mixing iodobenzenemethane and N-methylimidazole in a planetary ball mill using mechanochemical synthesis,and applied the product to passivate crystal defect energy levels in printable mesoscopic perovskite solar cells.Unlike ordinary thermochemical reactions,the reaction power of mechanochemistry is mechanical energy rather than thermal energy,so the reaction can be completed without high temperature,high pressure and other harsh conditions,and the whole experimental process is green and convenient.After dosage optimization,the short-circuit current density(J_(SC)),fill factor(FF)and photoelectric conversion efficiency(PCE)of the solar cells increase from 16.19 mA·cm^(-2),68.04%and 10.00%to 17.59 mA·cm^(-2),71.89%and 11.47%,respectively.Combining scanning electron microscopy(SEM)images,X-ray diffraction(XRD)tests,photoluminescence(PL)tests,time-resolved fluorescence spectroscopy(TRPL)tests,and X-ray photoelectron spectroscopy(XPS),we demonstrated that,on the one hand,the lone pair of electrons of the nitrogen atom on the imidazole ring has a dispersing effect on the charge of uncoordinated Pb^(2+)on the surface of the perovskite crystal,and on the other hand,the electrostatic interaction between the largeπ-bonded electron cloud of the benzene ring and I-has an inhibiting effect on the migration of I-,which in turn constrains the capture of excited state electrons by Pb^(2+)and iodine vacancies.Thus,we believe that the introduction of the rational ionic liquid 1-methyl-3-benzyl-imidazolium iodide effectively enhances the short-circuit current density(J_(SC))of the device,which opens a new pathway for the preparation and synthesis of new high-performance passivators.

关 键 词：离子液体 机械化学 可印刷介观钙钛矿太阳能电池 钝化 

分 类 号：O645.1[理学—物理化学] TM914.4[理学—化学]