The role of solvents in the formation of methylammonium lead triiodide perovskite  

作　　者：Junke Jiang Jose Manuel Vicent-Luna Shuxia Tao 

机构地区：[1]Materials Simulation andModelling.Department of Applied Physics,Eindhoven University of Technology.Eindhoven 5600 MB.the Netherlands [2]Center for Computational Energy Research,Department of Applied Physics,Eindhoven University of Technology.Eindhoven 5600 MB.the Netherlands

出　　处：《Journal of Energy Chemistry》2022年第5期393-400,共8页能源化学（英文版）

基　　金：funding by the Computational Sciences for Energy Research (CSER) tenure track program of Shell and NWO (Project No. 15CST04-2);funding by the Computational Sciences for Energy Research (CSER) tenure track program of Shell and NWO(Project No. 15CST04-2);funding support from the NWO START-UP from the Netherlands;the NWO START-UP from the Netherlands。

摘　　要：Metal halide perovskites(MHPs) are gaining increasing attention as low-cost, high-performance semiconductors for optoelectronics. In particular, their solution processing is compatible with the largescale manufacturing of thin-film devices, including solar cells and light-emitting diodes.Understanding the coordination chemistry in precursor-solvent solution and atomistic mechanisms of film formation is of great importance for optimizing the optoelectronic properties of the final films.Using the methylammonium lead triiodide(MAPbI_(3)) as an example, we study the complex evolution of the molecular species from the solution to the initial stage of the crystallization by using a combination of density functional theory(DFT) calculations and ab-initio molecular dynamics(AIMD) simulations. We focus on the widely employed solvents DMSO and DMF, analyze the structures and energies of the iodoplumbate complexes in the form of simple complex of [PbI_(m)L_(n)]^(2-m))_(x) and polymeric iodoplumbates of([PbI_(m)L_(n)]^(2-m))_(x). Based on the calculated formation enthalpies, we propose reaction schemes of MAPbI_(3) formation in DMSO, DMF and DMF-DMSO binary solvent and explain the advantages of the binary solvent.We highlight the important role of NH...O hydrogen bonds in the formation of iodoplumbates monomers.Our calculations indicate unbalanced reaction energies at several elementary reaction steps in either DMF(formation of [PbI_(4)L_(n)]^(2-) being highly favourable) or DMSO(formation of [PbI_(5)L_(n)]^(3- )being retarded).Mixing a small amount of DMSO in DMF gives rise to a better balance in the energies and, therefore,potentially better equilibria in the overall crystallization process and better quality of the final perovskite films.

关 键 词：MAPbI_(3) Perovskite formation Solvents DFT 

分 类 号：TB383.2[一般工业技术—材料科学与工程] TN03[电子电信—物理电子学]