Solar cell efficiencies - Stanford...
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Transcript of Solar cell efficiencies - Stanford...
Solar cell efficiencies
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Solar cell efficiencies
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Structure of (MA)PbI3 (MA = [CH3NH3]+)
Perovskite Structure
Halide perovskites: ABX3
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Structure of (MA)PbI3 (MA = [CH3NH3]+)
Perovskite Structure
Halide perovskites: ABX3
A-site cations: Rb+, Cs+, [CH3NH3]+, [(NH2)2CH]+
A site
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Structure of (MA)PbI3 (MA = [CH3NH3]+)
Perovskite Structure
Halide perovskites: ABX3
B-site cations: Mn2+, Cd2+, Cu2+, Sn2+, Ge2+,Pb2+
A-site cations: Rb+, Cs+, [CH3NH3]+, [(NH2)2CH]+
A site B site
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CNN. Published Jan. 22nd, 2016
Lead Toxicity
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CNN. Published Jan. 22nd, 2016
Lead Toxicity
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The only level of lead exposure not detrimental to human health is zero.
CNN. Published Jan. 22nd, 2016
Lead Toxicity
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The only level of lead exposure not detrimental to human health is zero.
620 mg of PbI2 can dissolve in 1 L of water
CNN. Published Jan. 22nd, 2016
Lead Toxicity
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The only level of lead exposure not detrimental to human health is zero.
620 mg of PbI2 can dissolve in 1 L of water
Systems to prevent lead exposure must be completely fail-safe.
Build a better perovskite
Reduce Toxicity
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Preserve 1.6 eV band gap
Deposition of films from solution
Defect tolerance
Build a better perovskite
Reduce Toxicity
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Preserve 1.6 eV band gap
Deposition of films from solution
Defect tolerance
Build a better perovskite
Reduce Toxicity
The lead perovskite electronic structure is key!
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Lead-halide perovskite band structure
Valence Band
Conduction Band
Eg
Halide p orbitals +
Pb s orbitals
Pb p orbitals
Lead-halide perovskite band structure
Valence Band
Conduction Band
Eg
Pb 82
207.2
Halide p orbitals +
Pb s orbitals
Pb p orbitals
Lead-halide perovskite band structure
Valence Band
Conduction Band
Eg
Pb 82
207.2
Pb2+ electronic configuration:
[Xe] 4f14 5d10 6s2 6p0
Halide p orbitals +
Pb s orbitals
Pb p orbitals
A brief jaunt around the periodic table
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A brief jaunt around the periodic table
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Hao, Stoumpos, Cao, Chang, Kanatzidis. Nature Photon. (2014) 8, 489. Noel, Stranks, Herz, Snaith, et al. Energy Environ. Sci. (2014) 7, 3061.
A brief jaunt around the periodic table
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Hao, Stoumpos, Cao, Chang, Kanatzidis. Nature Photon. (2014) 8, 489. Noel, Stranks, Herz, Snaith, et al. Energy Environ. Sci. (2014) 7, 3061.
A brief jaunt around the periodic table
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Hao, Stoumpos, Cao, Chang, Kanatzidis. Nature Photon. (2014) 8, 489. Noel, Stranks, Herz, Snaith, et al. Energy Environ. Sci. (2014) 7, 3061.
A brief jaunt around the periodic table
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Hao, Stoumpos, Cao, Chang, Kanatzidis. Nature Photon. (2014) 8, 489. Noel, Stranks, Herz, Snaith, et al. Energy Environ. Sci. (2014) 7, 3061.
A brief jaunt around the periodic table
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Hao, Stoumpos, Cao, Chang, Kanatzidis. Nature Photon. (2014) 8, 489. Noel, Stranks, Herz, Snaith, et al. Energy Environ. Sci. (2014) 7, 3061.
Double Perovskites (Elpasolites)
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ABX3
Double Perovskites (Elpasolites)
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A2BB’X6 ABX3
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138. Cs2AgBiBr6
Cs2AgBiBr6
Double Perovskites (Elpasolites)
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Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138. Cs2AgBiBr6
Cs2AgBiBr6
Double Perovskites (Elpasolites)
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Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138. Cs2AgBiBr6
Cs2AgBiBr6
Double Perovskites (Elpasolites)
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McClure, Ball, Windl, Woodward. Chem. Mater. (2016) 28, 1348. Cs2AgBiBr6 / Cs2AgBiCl6
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138. Cs2AgBiBr6
Cs2AgBiBr6
Double Perovskites (Elpasolites)
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McClure, Ball, Windl, Woodward. Chem. Mater. (2016) 28, 1348. Cs2AgBiBr6 / Cs2AgBiCl6
Volonakis, Filip, Snaith, Giustino, et al. J. Phys. Chem. Lett. (2016) 7, 1254. Cs2AgBiCl6
Wei, Deng, Bristowe, Cheetham, et al. Mater. Horiz. (2016) 3, 328. (MA)2KBiCl6
Deng, Wei, Cheetham, Bristowe, et al. J. Mater. Chem. A (2016) 4, 12025. (MA)2TlBiCl6
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Optical Properties
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
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Optical Properties
VB
CB Direct
Strong absorption
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
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Optical Properties
VB
CB Direct
Strong absorption
Indirect VB
CB
Weak absorption
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
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Optical Properties
Eg (indirect) = 1.95 eV
VB
CB Direct
Strong absorption
Indirect VB
CB
Weak absorption
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
Time-resolved photoluminescence
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𝐼 𝑡 ∝ ∆𝑛(𝑡)
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
Time-resolved photoluminescence
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𝐼 𝑡 = 𝐴 ∗ 𝑒−𝑡 𝜏⁄
𝐼 𝑡 ∝ ∆𝑛(𝑡)
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
Time-resolved photoluminescence
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𝐼 𝑡 = 𝐴 ∗ 𝑒−𝑡 𝜏⁄
𝐼 𝑡 ∝ ∆𝑛(𝑡)
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
Time-resolved photoluminescence
36 Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
𝐼 𝑡 = 𝐴 ∗ 𝑒−𝑡 𝜏⁄
𝐼 𝑡 ∝ ∆𝑛(𝑡)
Material Stability
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* = PbI2
Smith, Hoke, Solis-Ibarra, McGehee, Karunadasa. Angew. Chem. Int. Ed. (2014) 53, 11232
(MA)PbI3
Material Stability
38 Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
* = PbI2
Smith, Hoke, Solis-Ibarra, McGehee, Karunadasa. Angew. Chem. Int. Ed. (2014) 53, 11232
(MA)PbI3 Cs2AgBiBr6
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Material Stability: Heat
| | | | | | | | | | | | | | | | | = PbBr2 / PbI2
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
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Material Stability: Heat
| | | | | | | | | | | | | | | |
| | |
|
| |
| = PbBr2 / PbI2
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
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Material Stability: Heat
| | | | | | | | | | | | | | | |
| | |
|
| |
| = PbBr2 / PbI2
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
Summary
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
Cs2AgBiBr6
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Summary
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
Cs2AgBiBr6
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• First bismuth bromide perovskite
• Low toxicity • Moisture/heat resistant • Long carrier lifetimes
(660 ns)
Summary
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
Cs2AgBiBr6
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• First bismuth bromide perovskite
• Low toxicity • Moisture/heat resistant • Long carrier lifetimes
(660 ns) • Large band gap (1.95 eV) • Indirect band gap
Summary
Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
Cs2AgBiBr6
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• First bismuth bromide perovskite
• Low toxicity • Moisture/heat resistant • Long carrier lifetimes
(660 ns) • Large band gap (1.95 eV) • Indirect band gap
Double perovskites expand scope of halide perovskites beyond 2+ metals to include 1+ − 4+ metals at the B site.
Acknowledgments
Te Hu and Prof. Aaron Lindenberg Stanford Graduate Fellowship (SGF)
The Karunadasa Group!
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1.83 eV
Ephoton + Ephonon
1.83 eV
Ephoton + Ephonon
2.07 eV
Ephoton − Ephonon
Optical Properties
Ephoton
Ephonon
Ephoton
Ephonon
Edirect
Eg (indirect) = 1.95 eV
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CB
VB
Time-resolved photoluminescence
48 Slavney, Hu, Lindenberg, Karunadasa. J. Am. Chem. Soc. (2016) 138, 2138.
