钙钛矿太阳能电池的的研究进展

• Deposition methods • Sintering temperature • Microstructure
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Hole transport layer
• spiro-OMeTAD[1,5]
– Expensive – The low mobility (about 10-6 –10-5 cm2/Vs)[1] – Doping with cobalt electrolyte and Li salt – The highest efficiency(19.3) till now[5]
• Co-evaporation
– PbI2与CH3NH3I气相共蒸发沉积（真空下） – 杂质缺陷少、致密、一致性
• VASP
– 浸渍PbI2后气相CH3NH3I反应 – 高覆盖率、低粗糙度、大晶粒（微米级），so低表面复
合率、高开路电压
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Absorption spectra
◆ 19.3% 2019
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Hodes, G. (2019). "Perovskite-Based Solar Cells." Science 342(6156): 317-318.
Timeline of Perovskite solar cells
Al2O3 as e-collection layer Science, 2019, 338 (2019) 643-647.
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Shortages of Perovskite-based Solar Cells
• Oxygen sensitized[1] • Hydrolysis easily[2] • Degradation • Difficulty to fabricate large area continuously
Perovskite QDs as dye in DSSC Nanoscale, 2019, 3(10): 4088-4093. Perovskite as a dye in DSSC JACS, 131 (2009) 6050-6051.
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Interface engineering Science, 345 (2019) 542-546.
• Pyrene derivatives[2] • Thiopene derivatives[3] • PFB & TFB[4] • CuSCN or CuI • P3HT • PTAA • CuSnI3 • PCPDTBT
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Energy levels for different materials
perovskite film
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Architecture of perovskite solar cells
Mesoporous Structure
August 3wk.baidu.com 2020
Planar Structure
Fabrication Methods
• Solutions
– PbI2与CH3NH3I混合沉积 – 先PbI2后CH3NH3I – 溶液法方便，但不可控、有针孔、重复性低
• High Voc: ~1 V. vs VOC(silicon solar cell): 0.7V • Mono junction solar cell efficiency up to 20% [J. Phys. Chem. Lett., 4 (2019)
2423-2429]
• Stacking with Si-based solar cell efficiency up to 32%. [Science,2019,
photovoltages close to 1.0 V, much large than Si-based solar cell’s 0.7 V.
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J. Am. Chem. Soc. 131, 6050–6051 (2009).
Comparing the rate of increase in perovskite solar cell efficiencies
-3.62
CuSnI3
-4.92
e-selective materials
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photo absorbers h-transport materials
Materials Today 2019, 17(1): 16-23.
Al2O3 as e-selective layer
HTL films performance: spiro-OMeTAD > TFB > PFB > PFO
The order of electrical conductivities are σTFB > σspiro-OMeTAD > σPFB > σPFO.
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Adv. Funct. Mater. 2019, DOI: 10.1002/adfm.201901557
Substrates
• ITO on glass • FTO on glass • ITO on PET • FTO on PET
• Graphene • CNT
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Counter electrode
• Ag • Au • Pt • Graphite/carbon black
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Advantages of Perovskite-based Solar Cells
• Easy Fabricated (spin coated/Sintered at 80℃) • With good crystal properties. The bulk trap density of CH3NH3PbI3 is
exposed to air.
Organometal trihalide perovskite semiconductors (which have the formula (CH3NH3)PbX3, where Pb is lead and X can be iodine, bromine or chlorine) based solar cells have high
Nano Letters 2019, 14(2): 724-730.
Hole transport layer
Chemical structure of the HTL: Poly(9,9-dioctylfluorenyl-2,7-diyl (PFO) poly [(9,9-dioctylfl uorenyl-2,7-diyl)-co-(4,4′( N -(4-sec-butylphenyl)diphenylamine)] (TFB) poly(9,9-dioctylfluorene-co-bis-N, N-(4-butylphenyl) -bis-N, N-phenyl-1,4-phenylenediamine) (PFB).
论文发表情况
• Keyword: perovskite AND solar cell
August 3, 2020
Perovskite Materials for Photo Absorbers
• Organic-Inorganic Hybrid Materials • Structure: ABX3 • A: CH3NH3+, B: Pb2+, X: I-, Br-, or Cl• Direct band gap[1] • large absorption coefficient(similar to
344(6183): 458-458.
]
• Low Cost
– To put things in perspective, for a production capacity of 1000 GW per year, less than 10,000 tons of lead would be needed. Compare this with the 4 million tons per year of lead used for lead-acid batteries.
Al2O3 CH3NH3PbI3
spiro-OMeTAD
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Materials Today 2019, 17(1): 16-23.
Graphene/TiO2 as e-collection layers
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Graphene: Reduce series resistance Increase recombination resistance
Perovskite-based Solar Cells
CYQ
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Exploration of solid, cheap, stable dye as sensitizers for DSSCs
• CH3NH3PbBr3 is the first perovskite compound as dye to be introduced in DSSCs, the efficiency is 2.2%
Sequential solution deposition Nature 499, 316–319 (2019).
First planar heterostructure Nature 501, 395–398 (2019).
First introduction of spiro-MeOTAD as HTM (η: 9.7%) Sci. Rep. 2, 591 (2019)
silicon)[2] • high electrical mobility[3,4] • Large e/h transport length(100~1000
nm)[5,6]
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Properties of Perovskite absorbers
Band gap （eV）
n47T6P-4F8~05. ]× 1016/cm3，vs organic thin film: 1019/cm3. [Nat Mater, 2019, 13(5):
• very long e–h diffusion lengths of CH3NH3PbI3-xClx perovskites (on the order of 1 mm) [Science, 342 (2019) 341-344.]
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Energy Environ. Sci. 7, 399–407 (2019).
Electron selective layer
• TiO2 • SiO2 • ZrO2 • Al2O3 • ZnO
• Optimization:
– Graphene/TiO2[1] (15.6%)
Permittivity ε
激子束缚能 (meV)
Mobility
扩散长度
CH3NH3PbI3
1.5
4.8
CH3NH3PbBr3 2.3
6.5
CH3NH3PbCl3
CH3NH3PbI3– xClx
50
10~66
~100nm[1]
76
~1000nm[2]
CH3NH3PbI3–xClx中扩散长度高达 1 μm，高出材料的吸收长度近一个数量级。
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Optimization strategies for perovskite solar cells
• fine-tuning the perovskite chemical composition to improve film quality, suppression of the recombination could lead to VOC of around 1.1 V
• an efficiency of 3.8% on a CH3NH3PbI3-based cell was realized
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Principle of DSSCs
Perovskite-based solar cell
Lifetime is short. Continuous irradiation caused a photocurrent decay for an open cell