Controlled oxidation of Ni for stress-free hole transport layer of large-scale perovskite solar cells

  • Seongha Lee
  • Hee-Suk Roh
  • Gill Sang HanEmail author
  • Jung-Kun LeeEmail author
Research Article


The effect of the residual thermal stress of NiO films on the performance of an inverted type perovskite solar cell was studied. In this study, NiO films were grown on fluorine doped tin oxide (FTO) substrates of different surface roughness by thermally oxidizing Ni film and were tested as a hole transport layer for large-scale perovskite solar cells. Experimental and simulation results show that it is very important to suppress the appearance of the residual stress at the NiO-FTO interface during the oxidation of the Ni film for effective hole extraction. The Ni oxidation on the flat FTO film produced in-plane compressive stress in the NiO film due to the Ni film volume expansion. This led to the formation of defects including small blisters. These residual stress and defects increased leakage current through the NiO film, preventing holes from being selectively collected at the NiO-perovskite interface. However, when Ni was deposited and oxidized on the rough surface, the residual stress of the NiO film was negligible and its inherent high resistance was maintained. Stress-free NiO film is an excellent hole transport layer that stops the photogenerated electrons of the perovskite layer from moving to FTO. The improvements in the structural and electrical qualities of the NiO film by engineering the residual stress reduce the carrier recombination and increase the power conversion efficiency of the perovskite solar cells to 16.37%.


nickel oxidation surface roughness residual stress perovskite solar cells large scale processing 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.



This work was supported from the Global Frontier R&D Program on Center for Multiscale Energy System, Republic of Korea (No. 2012M3A6A7054855) and National Science Foundation (NSF 1709307).

Supplementary material

12274_2019_2556_MOESM1_ESM.pdf (2 mb)
Controlled oxidation of Ni for stress-free hole transport layer of large-scale perovskite solar cells


  1. [1]
    Leblebici, S. Y.; Leppert, L.; Li, Y. B.; Reyes-Lillo, S. E.; Wickenburg, S.; Wong, E.; Lee, J.; Melli, M.; Ziegler, D.; Angell, D. K. et al. Facet-dependent photovoltaic efficiency variations in single grains of hybrid halide perovskite. Nat. Energy2016, 1, 16093.CrossRefGoogle Scholar
  2. [2]
    Kim, H. S.; Lee, C. R.; Im, J. H.; Lee, K. B.; Moehl, T.; Marchioro, A.; Moon, S. J.; Humphry-Baker, R.; Yum, J. H.; Moser, J. E. et al. Lead iodide perovskite sensitized all-solid-state submicron thin film mesoscopic solar cell with efficiency exceeding 9%. Sci. Rep.2012, 2, 591.CrossRefGoogle Scholar
  3. [3]
    Jeon, N. J.; Noh, J. H.; Kim, Y. C.; Yang, W. S.; Ryu, S.; Seok, S. I. Solvent engineering for high-performance inorganic-organic hybrid perovskite solar cells. Nat. Mater.2014, 13, 897–903.CrossRefGoogle Scholar
  4. [4]
    Burschka, J.; Pellet, N.; Moon, S. J.; Humphry-Baker, R.; Gao, P.; Nazeeruddin, M. K.; Grätzel, M. Sequential deposition as a route to high-performance perovskite-sensitized solar cells. Nature2013, 499, 316–319.CrossRefGoogle Scholar
  5. [5]
    Ahn, N.; Son, D. Y.; Jang, I. H.; Kang, S. M.; Choi, M.; Park, N. G. Highly reproducible perovskite solar cells with average efficiency of 18.3% and best efficiency of 19.7% fabricated via Lewis base adduct of lead(II) iodide. J. Am. Chem. Soc.2015, 137, 8696–8699.CrossRefGoogle Scholar
  6. [6]
    Chen, B.; Yang, M. J.; Priya, S.; Zhu, K. Origin of J-V hysteresis in perovskite solar cells. J. Phys. Chem. Lett.2016, 7, 905–917.CrossRefGoogle Scholar
  7. [7]
    Han, G. S.; Shim, H. W.; Lee, S.; Duff, M. L.; Lee, J. K. Low-temperature modification of ZnO nanoparticles film for electron-transport layers in perovskite solar cells. ChemSusChem2017, 10, 2425–2430.CrossRefGoogle Scholar
  8. [8]
    Han, G. S.; Yoo, J. S.; Yu, F. D.; Duff, M. L.; Kang, B. K.; Lee, J. K. Highly stable perovskite solar cells in humid and hot environment. J. Mater. Chem. A2017, 5, 14733–14740.CrossRefGoogle Scholar
  9. [9]
    Heo, J. H.; Han, H. J.; Kim, D.; Ahn, T. K.; Im, S. H. Hysteresis-less inverted CH3NH3PbI3 planar perovskite hybrid solar cells with 18.1% power conversion efficiency. Energy Environ. Sci.2015, 8, 1602–1608.CrossRefGoogle Scholar
  10. [10]
    Norrman, K.; Madsen, M. V.; Gevorgyan, S. A.; Krebs, F. C. Degradation patterns in water and oxygen of an inverted polymer solar cell. J. Am. Chem. Soc.2010, 132, 16883–16892.CrossRefGoogle Scholar
  11. [11]
    Jørgensen, M.; Norrman, K.; Krebs, F. C. Stability/degradation of polymer solar cells. Sol. Eng. Mater. Sol. Cells2008, 92, 686–714.CrossRefGoogle Scholar
  12. [12]
    Kwon, U.; Kim, B. G.; Nguyen, D. C.; Park, J. H.; Ha, N. Y.; Kim, S. J.; Ko, S. H.; Lee, S.; Lee, D.; Park, H. J. Solution-processible crystalline NiO nanoparticles for high-performance planar perovskite photovoltaic cells. Sci. Rep.2016, 6, 30759.CrossRefGoogle Scholar
  13. [13]
    Wang, K. C.; Jeng, J. Y.; Shen, P. S.; Chang, Y. C.; Diau, W. G. G.; Tsai, C. H.; Chao, T. Y.; Hsu, H. C.; Lin, P. Y.; Chen, P. et al. P-type mesoscopic nickel oxide/organometallic perovskite heterojunction solar cells. Sci. Rep.2014, 4, 4756.CrossRefGoogle Scholar
  14. [14]
    Yin, X. T.; Guo, Y. X.; Xie, H. X.; Que, W. X.; Kong, L. B. Nickel oxide as efficient hole transport materials for perovskite solar cells. Sol. RRL2019, 3, 1900001.CrossRefGoogle Scholar
  15. [15]
    Yin, X. T.; Que, M. D.; Xing, Y. L.; Que, W. X. High efficiency hysteresisless inverted planar heterojunction perovskite solar cells with a solutionderived NiOx hole contact layer. J. Mater. Chem. A2015, 3, 24495–24503.CrossRefGoogle Scholar
  16. [16]
    Yin, X. W.; Yao, Z. B.; Luo, Q.; Dai, X. Z.; Zhou, Y.; Zhang, Y.; Zhou, Y. Y.; Luo, S. P.; Li, J. B.; Wang, N. et al. High efficiency inverted planar perovskite solar cells with solution-processed NiOx hole contact. ACS Appl. Mater. Interfaces2017, 9, 2439–2448.CrossRefGoogle Scholar
  17. [17]
    Eperon, G. E.; Burlakov, V. M.; Docampo, P.; Goriely, A.; Snaith, H. J. Morphological control for high performance, solution-processed planar heterojunction perovskite solar cells. Adv. Funct. Mater.2014, 24, 151–157.CrossRefGoogle Scholar
  18. [18]
    Li, G. J.; Jiang, Y. B.; Deng, S. B.; Tam, A.; Xu, P.; Wong, M.; Kwok, H. S. Overcoming the limitations of sputtered nickel oxide for high-efficiency and large-area perovskite solar cells. Adv. Sci.2017, 4, 1700463.CrossRefGoogle Scholar
  19. [19]
    Peng, Y. Y.; Cheng, Y. D.; Wang, C. H.; Zhang, C. J.; Xia, H. Y.; Huang, K. Q.; Tong, S. C.; Hao, X. T.; Yang, J. L. Fully doctor-bladed planar heterojunction perovskite solar cells under ambient condition. Org. Electron.2018, 58, 153–158.CrossRefGoogle Scholar
  20. [20]
    Wang, T.; Ding, D.; Wang, X.; Zeng, R. R.; Liu, H.; Shen, W. Z. Highperformance inverted perovskite solar cells with mesoporous NiOx hole transport layer by electrochemical deposition. ACS Omega2018, 3, 18434–18443.CrossRefGoogle Scholar
  21. [21]
    Seo, S.; Park, I. J.; Kim, M.; Lee, S.; Bae, C.; Jung, H. S.; Park, N. G.; Kim, J. Y.; Shin, H. An ultra-thin, un-doped NiO hole transporting layer of highly efficient (16.4%) organic-inorganic hybrid perovskite solar cells. Nanoscale2016, 8, 11403–11412.CrossRefGoogle Scholar
  22. [22]
    Pae, S. R.; Byun, S.; Kim, J.; Kim, M.; Gereige, I.; Shin, B. Improving uniformity and reproducibility of hybrid perovskite solar cells via a low-temperature vacuum deposition process for NiOx hole transport layers. ACS Appl. Mater. Interfaces2018, 10, 534–540.CrossRefGoogle Scholar
  23. [23]
    Park, J. H.; Seo, J.; Park, S.; Shin, S. S.; Kim, Y. C.; Jeon, N. J.; Shin, H. W.; Ahn, T. K.; Noh, J. H.; Yoon, S. C. et al. Efficient CH3NH3PbI3 perovskite solar cells employing nanostructured p-type NiO electrode formed by a pulsed laser deposition. Adv. Mater.2015, 27, 4013–4019.CrossRefGoogle Scholar
  24. [24]
    Mitra, R. Structural Intermetallics and Intermetallic Matrix Composites; CRC Press: Boca Raton, 2015.CrossRefGoogle Scholar
  25. [25]
    Unutulmazsoy, Y.; Merkle, R.; Fischer, D.; Mannhart, J.; Maier, J. The oxidation kinetics of thin nickel films between 250 and 500 °C. Phys. Chem. Chem. Phys.2017, 19, 9045–9052.CrossRefGoogle Scholar
  26. [26]
    Giovanardi, C.; di Bona, A.; Altieri, S.; Luches, P.; Liberati, M.; Rossi, F.; Valeri, S. Structure and morphology of ultrathin NiO layers on Ag(001). Thin Solid Films2003, 428, 195–200.CrossRefGoogle Scholar
  27. [27]
    Liu, C.; Huntz, A. M.; Lebrun, J. L. Origin and development of residual stresses in the Ni-NiO system: In-situ studies at high temperature by X-ray diffraction. Mater. Sci. Eng. A1993, 160, 113–126.CrossRefGoogle Scholar
  28. [28]
    Schade, H.; Smith, Z. E. Mie scattering and rough surfaces. Appl. Opt.1985, 24, 3221–3226.CrossRefGoogle Scholar
  29. [29]
    González-Alcalde, A. K.; Méndez, E. R.; Terán, E.; Cuppo, F. L. S.; Olivares, C. J. A.; García-Valenzuela, A. Reflection of diffuse light from dielectric one-dimensional rough surfaces. J. Opt. Soc. Am. A2016, 33, 373–382.CrossRefGoogle Scholar
  30. [30]
    Hutchinson, J. W. Stresses and Failure Modes in Thin films and Multilayers; Technical University of Denmark: Lyngby, 1996.Google Scholar
  31. [31]
    Nastasi, M.; Höchbauer, T.; Lee, J. K.; Misra, A.; Hirth, J. P. Nucleation and growth of platelets in hydrogen-ion-implanted silicon. Appl. Phys. Lett.2005, 86, 154102.CrossRefGoogle Scholar
  32. [32]
    Lee, J. K.; Lin, Y.; Jia, Q. X.; Höchbauer, T.; Jung, H. S.; Shao, L.; Misra, A.; Nastasi, M. Role of strain in the blistering of hydrogen-implanted silicon. Appl. Phys. Lett.2006, 89, 101901.CrossRefGoogle Scholar
  33. [33]
    Jamal, M. S.; Shahahmadi, S. A.; Chelvanathan, P.; Alharbi, H. F.; Karim, M. R.; Dar, M. A.; Luqman, M.; Alharthi, N. H.; Al-Harthi, Y. S.; Aminuzzaman, M. et al. Effects of growth temperature on the photovoltaic properties of RF sputtered undoped NiO thin films. Results Phys.2019, 14, 102360.CrossRefGoogle Scholar
  34. [34]
    Mahalingam, T.; John, V. S.; Ravi, G.; Sebastian, P. J. Microstructural characterization of electrosynthesized ZnTe thin films. Cryst Res. Technol.2002, 37, 329–339.CrossRefGoogle Scholar
  35. [35]
    Dabrowski, J.; Müssig, H. J. Silicon Surfaces and Formation of Interfaces: Basic Science in the Industrial World; World Scientific: Singapore, 2000; pp 414–416.CrossRefGoogle Scholar
  36. [36]
    Tosha, K.; Iida, K. Residual Stress and Hardness Distributions Induced by Shot Peening; International Scientific Committee for Shot Peening: Tokyo, Japan, 1990; pp 379–388.Google Scholar
  37. [37]
    Chen, X.; Vlassak, J. J. Numerical study on the measurement of thin film mechanical properties by means of nanoindentation. J. Mater. Res.2001, 16, 2974–2982.CrossRefGoogle Scholar
  38. [38]
    Pharr, G. M.; Oliver, W. C.; Brotzen, F. R. On the generality of the relationship among contact stiffness, contact area, and elastic modulus during indentation. J. Mater. Res.1992, 7, 613–617.CrossRefGoogle Scholar
  39. [39]
    Wang, Z. G. Influences of sample preparation on the indentation size effect & nanoindentation pop-in in nickel. Ph.D. Dissertation, University of Tennessee, Knoxville, 2012.Google Scholar
  40. [40]
    Fasaki, I.; Koutoulaki, A.; Kompitsas, M.; Charitidis, C. Structural, electrical and mechanical properties of NiO thin films grown by pulsed laser deposition. Appl. Surf. Sci.2010, 257, 429–433.CrossRefGoogle Scholar
  41. [41]
    De Los Santos Valladares, L.; Ionescu, A.; Holmes, S.; Barnes, C. H. W. Characterization of Ni thin films following thermal oxidation in air. J. Vac. Sci. Technol. B2014, 32, 051808.CrossRefGoogle Scholar
  42. [42]
    Zhang, J.; Zhang, L.; Dong, Y.; Li, H. Y.; Tan, C. M.; Xia, G.; Tan, C. S. The dependency of TSV keep-out zone (KOZ) on Si crystal direction and liner material. In 2013 IEEE International 3D Systems Integration Conference, San Francisco, CA, USA, 2013.Google Scholar

Copyright information

© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Mechanical Engineering and Materials ScienceUniversity of PittsburghPennsylvaniaUSA
  2. 2.School of Advanced Materials Science and EngineeringSungkyunkwan UniversitySuwonRepublic of Korea

Personalised recommendations