Crystal Structure Formation of CH3NH3PbI3-xClx Perovskite

Abstract

Inorganic-organic hydride perovskites bring the hope for fabricating low-cost and large-scale solar cells. At the beginning of the research, two open questions were raised: the hysteresis effect and the role of chloride. The presence of chloride significantly improves the crystallization and charge transfer property of the perovskite. However, though the long held debate over of the existence of chloride in the perovskite seems to have now come to a conclusion, no prior work has been carried out focusing on the role of chloride on the electronic performance and the crystallization of the perovskite. Furthermore, current reports on the crystal structure of the perovskite are rather confusing. This article analyzes the role of chloride in CH3NH3PbI3-xClx on the crystal orientation and provides a new explanation about the (110)-oriented growth of CH3NH3PbI3 and CH3NH3PbI3-xClx.

The Impact of a Dynamic Two‐Step Solution Process on Film Formation of Cs0.15(MA0.7FA0.3)0.85PbI3 Perovskite and Solar Cell Performance

“…Interestingly, in the static‐processed film, the (200) perovskite peak is the dominant peak and the (100) peak is negligible when it is first deposited (blue curve in Figure a). Similar results have also been reported in previous literature that the (200) phase is more dominant at low temperature while the formation of (100) perovskite requires subsequent annealing . On the contrary, in the dynamic‐processed film, the (100) perovskite peak already appears when it is first deposited indicating the favoring of this preferred perovskite orientation even before annealing.…”

Understanding Hydrogen Bonding Interactions in Crosslinked Methylammonium Lead Iodide Crystals: Towards Reducing Moisture and Light Degradation Pathways

“…[45][46][47] No other crystallographic reflections are distinguished in the XRD traces suggesting strong out-of-plane orientation and that the crystalline domains in the CH 3 NH 3 PbI 3Àx Cl x thin film are all preferentially oriented with their (110) planes parallel to the substrate.Therefore in this region of interest, degradation can then be examined by the evolution of any crystallographic planes associated with impurities.T his is done by monitoring the appearance of the degradation product-PbI 2 through the evolution of ar eflection peak at 12.68 8,w hich suggests the progression of the (001) crystallographic plane for this particular impurity.A na dditional reflection peak occasionally appears at 15.58 8 corresponding to the (100) crystallo- graphic plane for CH 3 NH 3 PbCl 3 .A sd epicted in Figure 2A, the XRD spectrum for apristine CH 3 NH 3 PbI 3Àx Cl x film shows major degradation (full evolution of ar eflection peak at 12.68 8)within 288 hofexposure to high moisture levels,while crosslinked CH 3 NH 3 PbI 3Àx Cl x crystals yield amoisture stability exceeding 720 h. We quantitatively determined the stability of the crosslinked CH 3 NH 3 PbI 3Àx Cl x crystals by calculating the intensity contribution of the (110) crystallographic plane for CH 3 NH 3 PbI 3Àx Cl x as afunction of moisture exposure ( Figure 2B). [45][46][47] No other crystallographic reflections are distinguished in the XRD traces suggesting strong out-of-plane orientation and that the crystalline domains in the CH 3 NH 3 PbI 3Àx Cl x thin film are all preferentially oriented with their (110) planes parallel to the substrate.Therefore in this region of interest, degradation can then be examined by the evolution of any crystallographic planes associated with impurities.T his is done by monitoring the appearance of the degradation product-PbI 2 through the evolution of ar eflection peak at 12.68 8,w hich suggests the progression of the (001) crystallographic plane for this particular impurity.A na dditional reflection peak occasionally appears at 15.58 8 corresponding to the (100) crystallo- graphic plane for CH 3 NH 3 PbCl 3 .A sd epicted in Figure 2A, the XRD spectrum for apristine CH 3 NH 3 PbI 3Àx Cl x film shows major degradation (full evolution of ar eflection peak at 12.68 8)within 288 hofexposure to high moisture levels,while crosslinked CH 3 NH 3 PbI 3Àx Cl x crystals yield amoisture stability exceeding 720 h. We quantitatively determined the stability of the crosslinked CH 3 NH 3 PbI 3Àx Cl x crystals by calculating the intensity contribution of the (110) crystallographic plane for CH 3 NH 3 PbI 3Àx Cl x as afunction of moisture exposure ( Figure 2B).…”

“…When the CH 3 NH 3 PbI 3Àx Cl x precursor solution containing the small crosslinking molecule is initially spincoated at 25 8 8C, the XRD traces of the resulting film show amajor peak at 2q of 14.28 8.This reflection peak can be assigned to the most intense (110) crystallographic plane of the I4cm tetragonal crystal structure of CH 3 NH 3 PbI 3 . [45][46][47] No other crystallographic reflections are distinguished in the XRD traces suggesting strong out-of-plane orientation and that the crystalline domains in the CH 3 NH 3 PbI 3Àx Cl x thin film are all preferentially oriented with their (110) planes parallel to the substrate.Therefore in this region of interest, degradation can then be examined by the evolution of any crystallographic planes associated with impurities.T his is done by monitoring the appearance of the degradation product-PbI 2 through the evolution of ar eflection peak at 12.68 8,w hich suggests the progression of the (001) crystallographic plane for this particular impurity.A na dditional reflection peak occasionally appears at 15.58 8 corresponding to the (100) crystallo-…”

Phenyl-C61-Butyric Acid Methyl Ester Hybrid Solution for Efficient CH3NH3PbI3 Perovskite Solar Cells

“…The HR-XRD data revealing the structural characteristics of the PCBM-MAPbI 3 films with (made from 0.1:1 solution) and without PCBM are shown in Figure 2. The diffraction pattern of MAPbI 3 exhibited peaks at 2θ = 13.97 • , 28.15 • , 40.63 • , and 42.78 • , corresponding to the (002), (004), (006), and (400) planes of the tetragonal crystal structure of perovskite, respectively [17,18]. As shown in Figure 2, the lattice diffraction peaks of the thin film based on the blend of MAPbI 3 and PCBM were consistent with those of the pristine MAPbI 3 film without PCBM.…”