SnO2基鈣鈦礦太陽能電池界面調控與性能優化

汪志鵬; 李瑞; 張梅; 郭敏

doi:10.13374/j.issn2095-9389.2021.08.13.004

SnO₂基鈣鈦礦太陽能電池界面調控與性能優化

doi: 10.13374/j.issn2095-9389.2021.08.13.004

汪志鵬^{1, 2},
李瑞^{1, 2},
張梅^{1, 2},
郭敏^{1, 2, ,}

1.
北京科技大學冶金與生態工程學院，北京 100083
2.
北京科技大學鋼鐵冶金新技術國家重點實驗室，北京 100083

基金項目: 國家自然科學基金資助項目（51572020, 51772023）

詳細信息

通訊作者:
E-mail: guomin@ustb.edu.cn

中圖分類號: O472
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出版歷程
- 收稿日期: 2021-08-13
- 網絡出版日期: 2021-11-11
- 刊出日期: 2023-02-01

Interface modification and performance optimization of SnO₂ based perovskite solar cells

WANG Zhi-peng^{1, 2},
LI Rui^{1, 2},
ZHANG Mei^{1, 2},
GUO Min^{1, 2
, ,}

1.
School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
2.
State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China

More Information

Corresponding author: E-mail: guomin@ustb.edu.cn

摘要

摘要: 近十余年來，鈣鈦礦太陽能電池光電轉換效率從3.8%提升至目前的25.5%，有望成為下一代商業用薄膜太陽能電池。然而，目前廣泛使用的TiO₂電子傳輸層電子遷移率低、退火溫度高、紫外光照穩定性差等特性使得TiO₂基鈣鈦礦太陽能電池性能，尤其是長期穩定性，面臨巨大挑戰。SnO₂由于良好的電子遷移率、適宜的能帶結構、簡單的低溫溶液合成以及穩定的化學結構等優點成為替代TiO₂電子傳輸層的首選。目前，調控SnO₂/鈣鈦礦以及鈣鈦礦/空穴傳輸層界面是SnO₂基鈣鈦礦太陽能電池性能優化的關鍵。鑒于此，在詳細介紹SnO₂電子傳輸層本體與表面，鈣鈦礦本體、晶界及表面缺陷類型及特征的基礎之上，重點總結了SnO₂/鈣鈦礦、鈣鈦礦/空穴傳輸層界面調控及性能提升的研究進展。最后，針對SnO₂基鈣鈦礦太陽能電池器件界面調控與性能優化的研究趨勢和發展方向做出展望。
- 鈣鈦礦太陽能電池 /
- SnO₂ /
- 缺陷鈍化 /
- 界面調控 /
- 性能優化
Abstract: Over the past decade, the power conversion efficiency of perovskite solar cells has increased from 3.8% to the current 25.5%, which is expected to become the next generation of commercial thin-film solar cells. However, the widely used TiO₂ electron transport layer has low electron mobility, requires a high annealing temperature, and has poor UV light stability, limiting the performance of TiO₂-based perovskite solar cells, especially long-term stability. SnO₂ is expected to be the first choice to replace TiO₂ electron transport layers because of its high electron mobility, suitable band structure, low-temperature solution synthesis, and stable chemical structure. Although the certified maximum efficiency of state-of-the-art SnO₂-based perovskite solar cells had exceeded 25%, it was still below its theoretical efficiency. Therefore, component engineering, interface engineering, solvent engineering, and other methods to improve the efficiency and stability of SnO₂-based perovskite solar cells have become a major research focus. Currently, regulating the SnO₂/perovskite and perovskite/hole transport layer interface is key to optimizing the performance of SnO₂-based perovskite solar cells. Most studies focused on improving the charge transport performance of SnO₂ and modifying the SnO₂/perovskite interface, while few studies have addressed defect passivation of the perovskite layer and the modification of the perovskite/SnO₂ interface. Therefore, it is essential to summarize the research progress of interface modification and performance optimization of SnO₂-based perovskite solar cells. This paper introduces the types and characteristics of defects in the bulk and surface of the SnO₂ electron transport layer, as well as defects in the bulk, grain boundaries, and surface of the perovskite film. The research progress of the interface modification (bulk and surface defect passivation) and performance improvement for the SnO₂ electron transport layer/perovskite and perovskite/hole transport layer are reviewed. Finally, the research directions of SnO₂-based perovskite solar cells on interface modification and performance optimization are presented.
- perovskite solar cells /
- SnO₂ /
- defect passivation /
- interface modification /
- performance optimization

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圖 1 常見的電子傳輸材料的晶體結構與能帶圖. (a) SnO₂晶體結構；(b) 常見電子傳輸層LUMO與HOMO能級（相對于真空能級E_vac）。

Figure 1. Crystal structures and band diagrams of common electron transport materials: (a) SnO₂ crystal structure；(b) LUMO and HOMO energy levels of the electron transport layers (vs E_vac)

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圖 2 SnO₂電子傳輸層常見的缺陷鈍化及界面調控示意圖（紫外臭氧處理、退火、摻雜、缺陷鈍化等）

Figure 2. Schematic diagram of common defect passivation and interface modification of the SnO₂ electron transport layer (UV ozone treatment, annealing, doping, defect passivation, etc.)

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圖 3 (NH₄)₂S鈍化SnO₂電子傳輸層缺陷. (a) SnO₂缺陷鈍化后FTIR測試結果^[57]；(b) SnO₂缺陷鈍化原理圖^[57]；(c) 甘氨酸鈍化SnO₂缺陷的原理圖^[53]；(d) 3-(1-吡啶基)-1-丙烷磺酸鹽鈍化SnO₂缺陷的原理圖^[61].

Figure 3. SnO₂ electron transport layer defects passivated by (NH₄)₂S: (a) SnO₂ FTIR test results after defect passivation^[57]; (b) SnO₂ defect passivation principle diagram^[57]; (c)principle diagram SnO₂ defect passivated by glycine ^[53];(d) passivation mechanism diagram SnO₂ defects passivated by 3-(1-pyridyl)-1-propane sulfonate ^[61]

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圖 6 鈣鈦礦缺陷鈍化原理圖. (a) 4-咪唑乙酸鹽酸鹽鈍化鈣鈦礦缺陷的原理圖^[67]；(b) PbI₂鈍化鈣鈦礦晶界^[83]

Figure 6. Schematic diagram of perovskite defect passivation: (a) schematic diagram of perovskite defects passivated by 4-imidazoleacetic acid hydrochloride ^[67]; (b) perovskite grain boundaries passivated by PbI₂ ^[83]

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圖 4 鈣鈦礦常見的缺陷示意圖. (a) 鈣鈦礦完美晶體; (b) MA⁺空位; (c) I^?空位; (d) Pb²⁺間隙; (e) I₃^-間隙; (f) Pb—I反占位; (g) Pb²⁺空位; (h) 晶界; (i) 表面懸掛鍵

Figure 4. Schematic diagram of common defects in perovskite: (a) perfect perovskite crystal; (b) MA⁺ vacancy; (c) I^? vacancy; (d) Pb²⁺ interstitial; (e) I₃^- interstitial; (f) Pb—I antisite; (g) Pb²⁺ vacancy; (h) grain boundary; (i) surface dangling bond

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圖 5 SnO₂基鈣鈦礦太陽能電池中鈣鈦礦常見的缺陷鈍化方法示意圖

Figure 5. Schematic diagram of common defect passivation methods in SnO₂-based perovskite solar cells

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表 1 不同制備方法對SnO₂晶體結構、帶隙（E_g）、電子遷移率（μ）、缺陷態密度（N_t）的影響

Table 1. Influence of preparation methods on SnO₂ crystal structure, bandgap (E_g), electron mobility (μ), defect state density (N_t)

Preparation method	Crystal structure	E_g/eV	μ /(cm²·V^?1·s^?1)	Electrical conductivity/(S·cm^?1)	N_t /cm^?3	Reference
Sol-gel	Rutile		9.92×10^?4		1.93×10¹⁶	[43]
CBD	Rutile	3.92		2.4×10^?3	2.17×10¹⁵	[35]
ALD	Amorphous	3.68	2.44×10^?6	2.09×10^?4		[36]
Dual-source combustion	Rutile	4.03		3.2×10^?6		[40]
Electrodeposition	Rutile	3.67		6.0x10^?8		[42]

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表 2 鈍化層鈍化SnO₂表面缺陷研究進展的總結：鈍化方式、鈍化物質/濃度、鈍化官能團、器件結構、有（W）無（WO）鈍化情況下器件性能參數

Table 2. Summary of research progress on SnO₂ surface defects passivated by the passivation layer: passivation materials, concentration, functional groups of the passivation material, device structure, device performance parameters with (W) without (WO) passivation.

Passivation materials	Device structure	PCE(WO/W)/%	Reference
Choline Chloride	Glass/ITO/Chol-SnO₂/MAPbI₃/Spiro-OMeTAD/Au	16.83/18.90	[12]
NPC₆₀-OH	Glass/ITO/SnO₂/ NPC₆₀-OH)/(FAMA)PbI₃/Spiro-OMeTAD/Ag	19.04/20.39	[62]
Dopamine	Glass/ITO/SnO₂/DA/MAPbI₃/Spiro-OMeTAD/Au	14.05/16.87	[65]
CH₃COOH	Glass/ITO/SnO₂/(CsFAMA)Pb(BrI)₃ /Spiro-OMeTAD/Au	18.84/20.56	[52]
Graphene quantum dots	Glass/ITO/SnO₂/GQDs/(FAMA)PbI_xCl_3-x/Spiro-OMeTAD/Ag	18.6/21.1	[69]
NH₂CHCOOH	Glass/ITO/SnO₂/Glycine/Cs_0.05FA_0.95-yMA_yPbI_1-xCl_x/Spiro-OMeTAD/Ag	18.82/20.63	[53]
KOH	Glass/ITO/SnO₂/KOH/CsPbI₂Br/carbon	8.59/10.7	[64]
Graphene quantum dots	Glass/FTO/GQDs：SnO₂/MAPbI₃/Spiro-OMeTAD/Au	13.61/16.54	[66]
Carbon quantum dots	Glass/FTO/SnO₂/GQDs/SnO₂/MAPbI₃/Spiro-OMeTAD/Ag	17.46/20.78	[70]
Fulleropyrrolidine(NMBF-Cl)	Glass/ITO/SnO₂/NMBF-Cl dimer/(FAPbI₃)_x(MAPbBr₃)_1?x/Spiro-OMeTAD/Ag	20.5/21.6	[71]
4-imidazoleacetic acid hydrochloride(ImAcHCl)	Glass/FTO/SnO₂/(FAPbI₃)_0.95(MAPbBr₃)_0.05/Spiro-MeOTAD/Au	19.53/20.96	[67]
NH₄F	Glass /ITO/SnO₂/(FAPbI₃)_0.95(MAPbBr₃)_0.05/spiro-OMeTAD/Au	22.4/23.2	[63]
potassium O-hexyl xanthate	Glass/ITO/SnO₂/MAPbI₃/Spiro-OMeTAD/Au	16.56/18.41	[72]
3-(1-pyridinio)-1-propanesulfonate	Glass/FTO/SnO₂/(CsFAMA)Pb(BrI)₃/Spiro-OMeTAD/Ag	19.63/21.43	[61]
CsAc	Glass/FTO/SnO₂/(FAPbI₃)_0.85(MAPbBr₃)_0.15/Spiro-OMeTAD/Au.	18.06/19.23	[73]
C₆₀ pyrrolidine tris-acid(CPTA)	PEN/ITO/SnO₂/CPTA/MAPbI₃/Spiro-OMeTAD/Au	15.35/18.36	[74]

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表 3 SnO₂基鈣鈦礦太陽能電池中鈣鈦礦層缺陷鈍化及Perovskite/HTL界面調控的研究進展總結：鈍化類型、鈍化劑、器件結構、有（W）無（WO）鈍化情況下器件效率

Table 3. Summary of research progress on defect passivation of the perovskite layer and Perovskite/HTL interface regulation in SnO₂-based perovskite solar cells: passivation type, passivating agent, device structure, PCE with (W) without (WO) passivation

Passivation type	Passivating agent	Device structure	PCE(WO/W)/%	Reference
Bulk defect passivation	EDACl₂	Glass/ITO/SnO₂/ (EDACl₂)/ (Cs_0.15FA_0.85PbI_2.7Br_0.3)/Carbon	15.60/18.80	[81]
	Potassium-intercalated rubrene (K₂Rubrene)	Glass/ITO/SnO₂ QD/(FAMA)Pb(IBr)₃/Spiro-OMeTAD/Au	17.82/18.14	[80]
	PEAI	Glass/ITO/SnO₂/FA_1?xMA_xPbI₃/Spiro-OMeTAD/Au	20.95/23.53	[3]
	Pb(SCN)₂	Glass/ITO/SnO₂/FA_0.4MA_0.6PbI_2.8-xBr_0.2(SCN)_x/Spiro-OMeTAD/Ag	17.13/19.64	[13]
Grain boundary defect passivation	PbI₂	Glass/ITO/SnO₂/(FAPbI₃)_1-x(MAPbBr₃)_x/Spiro-OMeTAD/Au	17.61/19.55	[82]
	M13 bacteriophage	Glass/ITO/SnO₂/MAPbI₃(M13)/Spiro-OMeTAD/Au	17.1/19.7	[84]
	NAMI	Glass/FTO/SnO₂/Cs_0.05(MA_0.15FA_0.85)_0.95Pb(I_0.85Br_0.15)₃/(NMA)₂PbI₄/Spiro-OMeTAD/Au	18.75/20.41	[85]
	PMAI	Glass/ITO/SnO₂/FA_1–xMA_xPMA_yPbI₃/Spiro-OMeTAD/Au	20.93/23.32	[86]
Surface defect passivation	MASCN、FASCN	Glass/FTO/SnO₂/ FAPbI₃/Spiro-OMeTAD/Au	?/23.1	[88]
	PAI	Glass/ITO/SnO₂/ (CsFAMA)PbI₃/Spiro-OMeTAD/Au	16.85/20.53	[89]
	BAI	Glass/FTO/SnO₂/PCBM/BA_0.05(FA_0.83Cs_0.17)_0.91Pb(I_0.8Br_0.2)₃/Spiro-OMeTAD/Au	16.9/20.6	[87]

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