空气下光诱导有机金属卤化钙钛矿薄膜的降解机理

引用本文: 葛杨, 牟许霖, 卢岳, 隋曼龄. 空气下光诱导有机金属卤化钙钛矿薄膜的降解机理[J]. 物理化学学报, 2020, 36(8): 1905039-0. doi: 10.3866/PKU.WHXB201905039 shu

Citation: Ge Yang, Mu Xulin, Lu Yue, Sui Manling. Photoinduced Degradation of Lead Halide Perovskite Thin Films in Air[J]. Acta Physico-Chimica Sinica, 2020, 36(8): 1905039-0. doi: 10.3866/PKU.WHXB201905039 shu

空气下光诱导有机金属卤化钙钛矿薄膜的降解机理

葛杨 ^1,2, ,
牟许霖 ^1,2, ,
卢岳 ^{1,2,
,} ,
隋曼龄 ^{1,2,
,}

1.
北京工业大学，固体微结构与性能研究所，北京 100124
2.
北京工业大学，固体微结构与性能北京市重点实验室

通讯作者: 卢岳, luyuerr@163.com; 隋曼龄, mlsui@bjut.edu.cn

基金项目:
国家重点研究发展计划(2016YFB0700700), 国家自然科学基金创新研究群体项目(51621003), 国家自然科学基金(11704015), 北京市教育委员会科研重点项目(KZ201310005002), 以及北京市科技创新服务能力建设-高精尖学科建设-材料科学与工程学科项目(PXM2019_014204_500031)资助

摘要: 近几年来钙钛矿材料作为新兴光伏材料取得了巨大的发展进步，但有机无机杂化钙钛矿较差的环境稳定性限制了它的大规模应用。因此深入研究钙钛矿材料的降解机制有助于开发更稳定的钙钛矿光伏器件。本文基于透射电子显微学的微观形貌观察、晶体结构及元素成分表征，详细研究了杂化钙钛矿CH₃NH₃PbI₃薄膜在光照以及空气共同作用下的降解机理。研究发现，光诱导下CH₃NH₃PbI₃薄膜会与空气中的氧气发生交互作用，同时生成六方晶态PbI₂甚至氧化为非晶态化合物PbI_2−2xO_x (0.4 < x < 0.6)，而其衰减位点主要存在于薄膜与空气接触的表面。降解过程中，由于存在着挥发性分解产物(I₂，CH₃NH₂)的大量丢失，薄膜的表面会产生许多小孔洞，继而形成一种蜂窝状的介孔衰竭通道。而这种衰竭方式主要与光照下钙钛矿中光生电子与氧气结合形成超氧根自由基(O₂^•−)有关，该基团诱导了CH₃NH₃PbI₃向PbI₂和非晶氧化态的转变。本文揭示了空气中光照诱导钙钛矿薄膜的降解机理，这将为未来设计和优化更稳定的钙钛矿太阳能电池提供全面的实验数据与理论支持。

关键词:

English

Photoinduced Degradation of Lead Halide Perovskite Thin Films in Air

Ge Yang ^1,2, ,
Mu Xulin ^1,2, ,
Lu Yue ^{1,2,
,} ,
Sui Manling ^{1,2,
,}

1.
Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing 100124, P. R. China
2.
Beijing Key Laboratory of Microstructure and Properties of Solids, Beijing University of Technology, Beijing 100124, P. R. China

Corresponding author: Email: luyuerr@163.com (Y.L.); Email: mlsui@bjut.edu.cn (M.S.). Tel.: +86-10-67396644

Received Date: 08 May 2019
Accepted Date: 06 June 2019
Revised Date: 05 June 2019
Available Online: 15 August 2020
Fund Project:
The project was supported by the National Key Research and Development Program of China (2016YFB0700700), the National Natural Science Fund for Innovative Research Groups, China (51621003), the National Natural Science Foundation of China (11704015), the Scientific Research Key Program of Beijing Municipal Commission of Education, China (KZ201310005002), and Beijing Municipal Found for Scientific Innovation, China (PXM2019_014204_500031)

Abstract: As an excellent photoelectric material, metal halide perovskites have been rapidly developed in the photovoltaic field. The power conversion efficiency of solar cells based on perovskite materials now exceeds 24%, which is close to the conversion efficiency of silicon-based solar cells. However, organic-inorganic hybrid perovskite materials are sensitive to light, oxygen, and moisture, particularly when combined in the ambient environment, limiting their commercial application in perovskite devices due to their poor environmental stability. Therefore, a comprehensive understanding of the degradation mechanism is the key for development of an effective method to inhibit the degradation of perovskite materials. Herein, the photo-induced degradation process of CH₃NH₃PbI₃ films in air was studied by conventional optical and structural characterization methods, including ultraviolet-visible (UV-Vis) absorption spectroscopy, X-ray diffraction (XRD) and advanced transmission electron microscopy (TEM) equipped with a probe spherical aberration corrector. The CH₃NH₃PbI₃ films were first decomposed into hexagonal PbI₂ and amorphous phase, and subsequently oxidized to the amorphous phase under the combined effects of light and oxygen. The molecular formula of the amorphous phase was further confirmed as PbI_2−2xO_x (0.4 < x < 0.6) via X-ray energy dispersive spectroscopy (EDS) and electron energy loss spectroscopy (EELS). Further analysis showed that the film degradation is mainly related to superoxide (O₂^•−) formed by combination of oxygen molecules and photoelectrons in the perovskite film. The organic part of the CH₃NH₃PbI₃ is oxidized by O₂^•− and CH₃NH₃PbI₃ is decomposed to form volatile products, such as CH₃NH₂ and I₂, then degraded into PbI₂, and oxidized to form the amorphous PbI_2−2xO_x. Therefore, during the initial degradation of film under light soaking in air, the degradation sites are mainly located at the interface between CH₃NH₃PbI₃ and air. Many pores were observed on the film surface due to the large loss of volatile decomposition products during the initial degradation. The films then converted to a honeycomb hollow morphology due to the continuous consumption of material under light soaking, reducing the mass of the film as well. Finally, the entire film was oxidized to form an amorphous structure. Herein, for the first time, we report that the formation of amorphous oxides is accompanied by the degradation of perovskite film. This study presents a new understanding of the photo-induced degradation mechanism of perovskite films in air and provides novel theoretical guidance to promote the long-term stability of perovskite solar cells.

Key words:

1. [1]
  De Wolf, S.; Holovsky, J.; Moon, S. J.; Loper, P.; Niesen, B.; Ledinsky, M.; Haug, F. J.; Yum, J. H.; Ballif, C. J. Phys. Chem. Lett. 2014, 5, 1035. doi: 10.1021/jz500279b doi: 10.1021/jz500279b
2. [2]
  Stranks, S. D.; Eperon, G. E.; Grancini, G.; Menelaou, C.; Alcocer, M. J.; Leijtens, T.; Herz, L. M.; Petrozza, A.; Snaith, H. J. Science 2013, 342, 341. doi: 10.1126/science.1243982 doi: 10.1126/science.1243982
3. [3]
  Wehrenfennig, C.; Eperon, G. E.; Johnston, M. B.; Snaith, H. J.; Herz, L. M. Adv. Mater. 2014, 26, 1584. doi: 10.1002/adma.201305172 doi: 10.1002/adma.201305172
4. [4]
  Steirer, K. X.; Schulz, P.; Teeter, G.; Stevanovic, V.; Yang, M.; Zhu, K.; Berry, J. J. ACS Energy Lett. 2016, 1, 360. doi: 10.1021/acsenergylett.6b00196 doi: 10.1021/acsenergylett.6b00196
5. [5]
  Jeon, N. J.; Noh, J. H.; Kim, Y. C.; Yang, W. S.; Ryu, S.; Seok, S. I. Nat. Mater. 2014, 13, 897. doi: 10.1038/nmat4014 doi: 10.1038/nmat4014
6. [6]
  Kojima, A.; Teshima, K.; Shirai, Y.; Miyasaka, T. J. Am. Chem. Soc. 2009, 131, 6050. doi: 10.1021/ja809598r doi: 10.1021/ja809598r
7. [7]
  https://www.nrel.gov/pv/assets/pdfs/best-reserch-cell-efficiencies (accessed May 1, 2019).
8. [8]
  Tang, X. F.; Brandl, M.; May, B.; Levchuk, I.; Hou, Y.; Richter, M.; Chen, H. W.; Chen, S.; Kahmann, S.; Osvet, A.; et al. J. Mater. Chem. A 2016, 4, 15896. doi: 10.1039/c6ta06497c doi: 10.1039/c6ta06497c
9. [9]
  Yang, J. L.; Siempelkamp, B. D.; Liu, D. Y.; Kelly, T. L. ACS Nano 2015, 9, 1955. doi: 10.1021/nn506864k doi: 10.1021/nn506864k
10. [10]
  Aristidou, N.; Sanchez-Molina, I.; Chotchuangchutchaval, T.; Brown, M.; Martinez, L.; Rath, T.; Haque, S. A. Angew. Chem. Int. Ed. 2015, 54, 8208. doi: 10.1002/anie.201503153 doi: 10.1002/anie.201503153
11. [11]
  Nie, W.; Tsai, H.; Asadpour, R.; Blancon, J. C.; Neukirch, A. J.; Gupta, G.; Crochet, J. J.; Chhowalla, M.; Tretiak, S.; Alam, M. A.; et al. Science 2015, 347, 522. doi: 10.1126/science.aaa0472 doi: 10.1126/science.aaa0472
12. [12]
  Zhou, Y.; Yang, M.; Vasiliev, A. L.; Garces, H. F.; Zhao, Y.; Wang, D.; Pang, S.; Zhu, K.; Padture, N. P. J. Mater. Chem. A 2015, 3, 9249. doi: 10.1039/c4ta07036d doi: 10.1039/c4ta07036d
13. [13]
  Chen, H. Adv. Funct. Mater. 2017, 27, 1605654. doi: 10.1002/adfm.201605654 doi: 10.1002/adfm.201605654
14. [14]
  晒旭霞, 李丹, 刘双双, 李浩, 王鸣魁.物理化学学报, 2016, 32, 2159.] doi: 10.3866/PKU.WHXB201606072Shai, X. X.; Li, D.; Liu, S. S.; Li, H.; Wang, M. K. Acta Phys. -Chim. Sin. 2016, 32, 2159. doi: 10.3866/PKU.WHXB201606072
15. [15]
  Rong, Y.; Hu, Y.; Mei, A.; Tan, H.; Saidaminov, M. I.; Seok, S. I.; McGehee, M. D.; Sargent, E. H.; Han, H. Science 2018, 361, eaat8235. doi: 10.1126/science.aat8235 doi: 10.1126/science.aat8235
16. [16]
  黄杨, 孙庆德, 徐文, 何垚, 尹万健.物理化学学报, 2017, 33, 1730.] doi: 10.3866/PKU.WHXB201705042Huang, Y; Sun, Q. D.; Xu, W.; He, Y.; Yin, W. J. Acta Phys. -Chim. Sin. 2017, 33, 1730. doi: 10.3866/PKU.WHXB201705042
17. [17]
  Boyd, C. C.; Cheacharoen, R.; Leijtens, T.; McGehee, M. D. Chem. Rev. 2018, 119, 3418. doi: 10.1021/acs.chemrev.8b00336 doi: 10.1021/acs.chemrev.8b00336
18. [18]
  Sun, Q.; Fassl, P.; Becker-Koch, D.; Bausch, A.; Rivkin, B.; Bai, S.; Hopkinson, P. E.; Snaith, H. J.; Vaynzof, Y. Adv. Energy Mater. 2017, 7, 1700977. doi:10.1002/aenm.201700977 doi: 10.1002/aenm.201700977
19. [19]
  Bryant, D.; Aristidou, N.; Pont, S.; Sanchez-Molina, I.; Chotchunangatchaval, T.; Wheeler, S.; Durrant, J. R.; Haque, S. A. Energy Environ. Sci. 2016, 9, 1655. doi: 10.1039/c6ee00409a doi: 10.1039/c6ee00409a
20. [20]
  Aristidou, N.; Eames, C.; Sanchez-Molina, I.; Bu, X.; Kosco, J.; Islam, M. S.; Haque, S. A. Nat. Commun. 2017, 8, 15218. doi: 10.1038/ncomms15218 doi: 10.1038/ncomms15218
21. [21]
  Lee, M. M.; Teuscher, J.; Miyasaka, T.; Murakami, T. N.; Snaith, H. J. Science 2012, 338, 643. doi: 10.1126/science.1228604 doi: 10.1126/science.1228604
22. [22]
  Wu, Y.; Islam, A.; Yang, X.; Qin, C.; Liu, J.; Zhang, K.; Peng, W.; Han, L. Energy Environ. Sci. 2014, 7, 2934. doi: 10.1039/c4ee01624f doi: 10.1039/c4ee01624f
23. [23]
  Ouyang, Y.; Shi, L.; Li, Q.; Wang, J. Small Methods 2019, 1900154. doi: 10.1002/smtd.201900154 doi: 10.1002/smtd.201900154
24. [24]
  Li, Y.; Zhao, Z.; Lin, F.; Cao, X.; Cui, X.; Wei, J. Small 2017, 13, 1604125. doi:10.1002/smll.201604125 doi: 10.1002/smll.201604125
25. [25]
  Rothmann, M. U.; Li, W.; Zhu, Y.; Liu, A.; Ku, Z. L.; Bach, U.; Etheridge, J.; Cheng, Y. B. Adv. Mater. 2018, 30, 1802769. doi: 10.1002/adma.201802769 doi: 10.1002/adma.201802769
26. [26]
  Pennycook, S. J.; Nellist, P. D. Z-Contrast Scanning Transmission Electron Microscopy. In Impact of Electron and Scanning Probe Microscopy on Materials Research; Rickerby, D. G., Valdrè, G., Valdrè, U., Eds.; Springer Netherlands: Dordrecht, The Netherlangds, 1999; pp. 161–207.
27. [27]
  Jung, H. J.; Kim, D.; Kim, S.; Park, J.; Dravid, V. P.; Shin, B. Adv. Mater. 2018, 30, e1802769. doi: 10.1002/adma.201802769 doi: 10.1002/adma.201802769

扫一扫看文章

计量

PDF下载量: 0
文章访问数: 32
HTML全文浏览量: 3

通讯作者: 陈斌, bchen63@163.com

1.
沈阳化工大学材料科学与工程学院沈阳 110142

空气下光诱导有机金属卤化钙钛矿薄膜的降解机理

通讯作者: 卢岳, luyuerr@163.com; 隋曼龄, mlsui@bjut.edu.cn

English

Photoinduced Degradation of Lead Halide Perovskite Thin Films in Air

Corresponding author: Email: luyuerr@163.com (Y.L.); Email: mlsui@bjut.edu.cn (M.S.). Tel.: +86-10-67396644

计量

文章相关

通讯作者: 陈斌, bchen63@163.com

中国化学会秘书处