Compositions and methods for modifying perovskite surfaces
The present disclosure relates to a composition that includes a first layer that includes a perovskite and a second layer that includes a perovskitoid, where the perovskite has a first crystalline structure defined by ABX 3 , the perovskitoid has a second crystalline structure defined by A′B 2 X 6 , where A is a first cation, B is a second cation, X is an anion, and A′ is a third cation having either a 1+ charge or a 2+ charge.
1. A composition comprising:
a first layer comprising a perovskite; and
a second layer comprising a perovskitoid, wherein:
the perovskite has a first crystalline structure comprising ABX 3 ,
the perovskitoid has a second crystalline structure comprising A′B 2 X 6 ,
A comprises a first cation, B comprises a second cation, X comprises an anion, and A′ comprises a third cation having either a 1+ charge or a 2+ charge.
2. The composition of claim 1 , wherein A′ has a characteristic length between 2.53 Å and 7.62 Å.
3. The composition of claim 2 , wherein the characteristic length is between 2.72 Å and 7.06 Å.
4. The composition of claim 1 , wherein the second crystalline structure comprises a 3D crystal structure.
5. The composition of claim 4 , wherein the 3D structure has a centrosymmetric orthorhombic space group Pbam.
6. The composition of claim 1 , wherein the second crystalline structure is characterized by having at least one octahedra dimer having a composition consisting of Pb 2 I 6 2− .
7. The composition of claim 1 , wherein A′ comprises at least one of N-methyl-1,3-propane diammonium (Me-PDA) or 1,4-bis(aminomethyl)benzene (p-PBA).
8. The composition of claim 7 , wherein the second crystalline structure comprises at least one of (Me-PDA)Pb 2 I 6 or (p-PBA)Pb 2 I 6 .
9. The composition of claim 1 , wherein:
the perovskite comprises FA 1−x−y MA x C Sy Pb(I 1−z Br z ) 3 ,
0≤x≤1, 0≤y≤1, and 0≤z≤1.
10. The composition of claim 1 , wherein the second layer has a surface roughness less than or equal to about 16 nm.
11. The composition of claim 1 , wherein the composition has a yield mobility product (φΣμ) of at least about 50.0 cm 2 /Vs.
12. The composition of claim 1 , wherein the composition has a charge-carrier lifetime of at least about 1.5 microseconds.
13. The composition of claim 1 , wherein the composition has an out-of-plane charge transport between (1-3)×10 −3 cm 2 V −1 s −1 and 1×10 −1 cm 2 V −1 s −1 .
14. The composition of claim 1 , wherein the second layer uniformly covers the first layer.
15. The composition of claim 1 , wherein the first layer has a thickness between about 100 nm and about 2000 nm.
16. The composition of claim 1 , wherein the second layer has a thickness between about 1 nm and about 100 nm.
17. The composition of claim 1 , wherein the composition has a charge-carrier lifetime between 1.5 microseconds and 5.0 microseconds.
18. The composition of claim 1 , wherein the composition is characterized by a peak at less than 10°, as measured by XRD.
19. A device comprising:
a first layer comprising a perovskite; and
a second layer comprising a perovskitoid, wherein:
the perovskite has a first crystalline structure comprising ABX 3 ,
the perovskitoid has a second crystalline structure comprising A′B 2 X 6 ,
A comprises a first cation, B comprises a second cation, X comprises an anion, and A′ comprises a third cation having either a 1+ charge or a 2+ charge.
20. A device comprising, in order:
a glass substrate;
a layer comprising fluorine-doped tin oxide;
a layer comprising compact TiO 2 ;
a layer comprising mesoporous TiO 2 ;
a layer comprising a perovskite;
a layer comprising a perovskitoid;
a layer comprising a hole-transport material (HTL); and
a metal layer, wherein:
the perovskite has a first crystalline structure comprising ABX 3 ,
the perovskitoid has a second crystalline structure comprising A′B 2 X 6 ,
A comprises a first cation, B comprises a second cation, X comprises an anion, and A′ comprises a third cation having either a 1+ charge or a 2+ charge.