标题：Modifying CH3NH3PbBr3 nanocrystals with arylamines
作者：Zhu, Ruimin; Liu, Heyuan; Shen, Li; Sun, Dejun; Li, Xiyou
作者机构：[Zhu, Ruimin; Sun, Dejun; Li, Xiyou] Shandong Univ, Dept Chem, Jinan 250100, Shandong, Peoples R China.; [Liu, Heyuan; Shen, Li; Li, Xiyou] China Un 更多
通讯作者：Sun, DJ;Li, XY
通讯作者地址：[Sun, DJ; Li, XY]China Univ Petr East China, Coll Sci, Qingdao 266580, Peoples R China.
来源：JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
关键词：CH3NH3PbBr3 perovskite nanocrystals; Arylamine; Surface; functionalization; Steric hindrance; Alkalinity
摘要：Chemically decorating CH3NH3PbBr3 with a group of para-substituted arylamine (R-An) was investigated, where R ranges from electron-withdrawing trifluoromethoxy(-CF3O), to hydrogen or electron-donating ethoxy (-EtO). Different ratios of R-An ammonium bromide and methylammonium bromide (MA) (R-An/MA=3/7, 4/6, 5/5, 6/4 and 7/3) were tested. XRD patterns revealed that the perovskite nanocomposite were cubic with good crystallinity. TEM and photoluminescence suggested that the perovskite nanocrystals were composed of 2D layered and 3D bulk structures. H-1 NMR and TGA experiments revealed that the non-substituted aniline can readily adsorb to the surface of perovskite at any ratios between R-An and MA. But an EtOAn/MA ratio >= 1 is needed to anchor the EOAn molecules on the surface of perovskite. For the arylamine with the electron withdrawing -CF3O group, it cannot adsorb to the surface of the perovskite at any concentrations. This result reveals that both steric hindrance and alkalinity can affect the anchoring of arylamine on the surface of CH3NH3PbBr3 perovskite. I-V curves of the perovskite nanocrystal films prepared by spin coating suggest that proper surface modification can increase the conductivity significantly.