Fig. 1. Unit cell of an ideal cubic perovskite ABX
3 (left), and their extended crystalline structured connected by corner-sharing [BX
6]
4- octahedra (right). Reproduced with permission
[5]. Copyright 2016, Wiley-VCH
Fig. 2. The top layer atoms and simulated STM images
[33]. Copyright 2017, American Chemical Society
Fig. 3. TGA curve of CH
3NH
3PbI
3 decomposition
[48]. Copyright 2014, American Chemical Society
Fig. 4. The PL image of a large number of samples of MAPbI
3 excited by a commercial color camera at 458 nm before degradation, in which the pure MAPbI
3 structure is seen as red (left image); the right image is another image of the same area after degradation, in which green emission is observed, corresponding Launched on PbI
[52]2.Copyright 2016, American Chemical Society
Fig. 5. Synthetic procedure for perovskite nanocrystals
[55]. Copyright 2016, Wiley-VCH
Fig. 6. The top-down synthetic method towards methylammonium lead halide perovskite nanocrystals
[58]. Copyright 2017, Wiley-VCH
Fig. 7. Schematic of the ABX
3 perovskite crystal structure (left); Elements that are used as ions in the mixed-metal perovskite materials (right)
[59].Copyright 2017, Royal Society of Chemistry
Fig. 8. Regular (PbI
6) octahedral chain in CH
3NH
3PbI
3 (left) and distorted chain in 12.5 at.% Cs-doped CH
3NH
3PbI
3 (right). (Gray/Purple/Brown/Blue/Pink/Turquoise sphere represents Pb/I/C/N/H/Cs atom)
[66] Fig. 9. Schematic overview of contraction of octahedral after partially replacing Pb
2+ by smaller Zn
2+ ions
[72] Fig. 10. The local geometry and the electron localization function (ELF) contour plots of MAPbI
3Cl
3-x before and after Zn doping
[69].
Copyright 2018,Elsevier
Fig. 11. Schematics formation of perovskite layer with and without addition of Ni
2+ metal ions, scanning electron microscopy images of PbI
2 films with various NiCl
2:PbI
2 molar ratio, SEM images of corresponding perovskite films
[70]. Copyright 2018, Wiley-VCH
Fig. 12. The crystal structure of pristine MAPbI
3 (left) and MAPbI
3 (Ni) perovskite (right), in which Ni-I and Ni-N bonds are indicated with green lines
[70]. Copyright 2018, Wiley-VCH
Fig. 13. Perovskite structures of CH
3NH
3Pb (SCN)
2I (left) and CH
3NH
3PbI
3 (right) for comparison. Carbon gray, iodine red, lead pink, nitrogen blue, sulfur yellow
[80]. Copyright 2015, Wiley-VCH
Fig. 14. SEM images of CH
3NH
3Pb(SCN)
xI
3-x film prepared using DMF as the solvent of Pb(SCN)
2 and pure CH
3NH
3PbI
3 film (right)
[79]. Copyright 2019, American Chemical Society
Fig. 15. Schematic device structure of a MAPbI
3/UCns bilayer photodetector and scanning electron microscopy and transmission electron microscopy of the neat UCns layer, MAPbI
3 arrays and bilayer
[56]. Copyright 2017, American Chemical Society
Fig. 16. Detectivity and responsivity as a function of time showing long-term environmental stability for MAPbI
3/UCns bilayer and the neat MAPbI
3 photodetectors exposure under ambient condition with 30-40% relative humidity (RH)
[56]. Copyright 2017, American Chemical Society
Fig. 17. Water soaking showing strong water resistance of the MAPbI
3/UCns bilayer in contrast to the neat MAPbI
3 film
[56].
Copyright 2017, American Chemical Society
Fig. 18. Schematic configuration photodetector and cross-section SEM image of CH
3NH
3PbI
3/C8BTBT heterojunction thin films, and XRD spectra of CH
3NH
3PbI
3 (black) and CH
3NH
3PbI
3/C8BTBT heterojunction (red) thin films
[83]. Copyright 2017, Wiley-VCH
Fig. 19. Photocurrent and responsivity of CH
3NH
3PbI
3 and CH
3NH
3PbI
3/C8BTBT heterojunction photodetectors measured in ambient condition for 20 days
[83]. Copyright 2017, Wiley-VCH
Phase | Temperature/K | Crystal system | Space group | Lattice/ parameters(0.1nm) |
---|
CH3NH3PbCl3 | | | | | α | >178.8 | Cubic | Pm3m | a=5.675 | β | 172.9~178.8 | Tetragonal | P4/mmm | a=5.655 | c=5.630 | γ | <172.9 | Orthorhombic | P2221 | a=5.673 b=5.628 c=11.182 | CH3NH3PbBr3 | | | | | α | >236.9 | Cubic | Pm3m | a=5.901 | β | 155.1~236.9 | Tetragonal | I4/mcm | a=8.322 | c=11.833 | γ | 149.5~155.1 | Tetragonal | P4/mmm | a=5.894 2 | c=5.861 2 | δ | <144.5 | Orthorhombic | Pna21 | a=7.979 | b=8.580 | c=11.849 | CH3NH3PbI3 | | | | | α | 400 | Tetragonal | P4mm | a=6.311 5 | | | | | b=6.311 5 c=6.316 1 | β | 293 | Tetragonal | I4cm | a=8.849 b=8.849 | c=12.642 | γ | 162~172 | Orthorhombic | Pna21 | a=5.673 b=8.581 | c=11.182 |
|
Table 1. The influence of temperature on the crystal structure and parameters of perovskite materials
[31,39,50]