Minimizing hydrogen vacancies to enable highly efficient hybrid perovskites
Source abstract
Abstract
Defect-induced non-radiative losses are currently limiting the performance of hybrid perovskite devices. Experimental reports have indicated the existence of point defects that act as detrimental non-radiative recombination centres under iodine-poor synthesis conditions. However, the microscopic nature of these defects is still unknown. Here we demonstrate that hydrogen vacancies can be present in high densities under iodine-poor conditions in the prototypical hybrid perovskite MAPbI3 (MA = CH3NH3). They act as very efficient non-radiative recombination centres with an exceptionally high carrier capture coefficient of 10-4 cm3 s-1. By contrast, the hydrogen vacancies in FAPbI3 [FA = CH(NH2)2] are much more difficult to form and have a capture coefficient that is three orders of magnitude lower. Our study unveils the critical but overlooked role of hydrogen vacancies in hybrid perovskites and rationalizes why FA is essential for realizing high efficiency in hybrid perovskite solar cells. Minimizing the incorporation of hydrogen vacancies is key to enabling the best performance of hybrid perovskites.
Source: europepmc · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Perovskite Materials and Applications · Solid-state spectroscopy and crystallography · Chalcogenide Semiconductor Thin Films
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (37)
Show source-provided references
1. Best Research-Cell Efficiency Chart (NREL, accessed 25 September 2020); https://www.nrel.gov/pv/assets/pdfs/best-research-cell-efficiencies.20200925.pdf
2. Yang, W. S. et al. Iodide management in formamidinium-lead-halide-based perovskite layers for efficient solar cells. Science 356, 1376–1379 (2017).10.1126/science.aan2301 ↗
3. Abdi-Jalebi, M. et al. Maximizing and stabilizing luminescence from halide perovskites with potassium passivation. Nature 555, 497–501 (2018).10.1038/nature25989 ↗
4. Du, M.-H. Density functional calculations of native defects in CH3NH3PbI3: effects of spin–orbit coupling and self-interaction error. J. Phys. Chem. Lett. 6, 1461–1466 (2015).10.1021/acs.jpclett.5b00199 ↗
5. Meggiolaro, D. et al. Iodine chemistry determines the defect tolerance of lead-halide perovskites. Energy Environ. Sci. 11, 702–713 (2018).10.1039/C8EE00124C ↗
6. Zhang, X., Turiansky, M. E. & Van de Walle, C. G. Correctly assessing defect tolerance in halide perovskites. J. Phys. Chem. C 124, 6022–6027 (2020).10.1021/acs.jpcc.0c01324 ↗
7. Zhang, X., Turiansky, M. E., Shen, J.-X. & Van de Walle, C. G. Iodine interstitials as a cause of nonradiative recombination in hybrid perovskites. Phys. Rev. B 101, 140101(R) (2020).10.1103/PhysRevB.101.140101 ↗
8. Zhang, X., Shen, J.-X., Turiansky, M. E. & Van de Walle, C. G. Hidden role of Bi incorporation in nonradiative recombination in methylammonium lead iodide. J. Mater. Chem. A 8, 12964–12967 (2020).10.1039/D0TA04968A ↗
9. Jeon, N. J. et al. Compositional engineering of perovskite materials for high-performance solar cells. Nature 517, 476–480 (2015).10.1038/nature14133 ↗
10. Saliba, M. et al. Cesium-containing triple cation perovskite solar cells: improved stability, reproducibility and high efficiency. Energy Environ. Sci. 9, 1989–1997 (2016).10.1039/C5EE03874J ↗
11. Min, H. et al. Efficient, stable solar cells by using inherent bandgap of α-phase formamidinium lead iodide. Science 366, 749–753 (2019).10.1126/science.aay7044 ↗
12. Lu, H. et al. Vapor-assisted deposition of highly efficient, stable black-phase FAPbI3 perovskite solar cells. Science 370, eabb8985 (2020).10.1126/science.abb8985 ↗
13. Yin, W.-J., Shi, T. & Yan, Y. Unusual defect physics in CH3NH3PbI3 perovskite solar cell absorber. Appl. Phys. Lett. 104, 063903 (2014).10.1063/1.4864778 ↗
14. Ming, W., Chen, S. & Du, M.-H. Chemical instability leads to unusual chemical-potential-independent defect formation and diffusion in perovskite solar cell material CH3NH3PbI3. J. Mater. Chem. A 4, 16975–16981 (2016).10.1039/C6TA07492H ↗
15. Meggiolaro, D. & De Angelis, F. First-principles modeling of defects in lead halide perovskites: best practices and open issues. ACS Energy Lett. 3, 2206–2222 (2018).10.1021/acsenergylett.8b01212 ↗
16. Heyd, J., Scuseria, G. E. & Ernzerhof, M. Hybrid functionals based on a screened Coulomb potential. J. Chem. Phys. 118, 8207–8215 (2003).10.1063/1.1564060 ↗
17. Bagraev, N. & Mashkov, V. A mechanism for two-electron capture at deep level defects in semiconductors. Solid State Commun. 65, 1111–1117 (1988).10.1016/0038-1098(88)90904-0 ↗
18. Alkauskas, A., Yan, Q. & Van de Walle, C. G. First-principles theory of nonradiative carrier capture via multiphonon emission. Phys. Rev. B 90, 075202 (2014).10.1103/PhysRevB.90.075202 ↗
19. Henry, C. H. & Lang, D. V. Nonradiative capture and recombination by multiphonon emission in GaAs and GaP. Phys. Rev. B 15, 989–1016 (1977).10.1103/PhysRevB.15.989 ↗
20. Suppan, P. in Photoinduced Electron Transfer IV, Vol. 163 (Ed. Mattay, J.) 95–130 (Springer, 1992).10.1007/3-540-55117-4_5 ↗
21. Yamada, Y., Nakamura, T., Endo, M., Wakamiya, A. & Kanemitsu, Y. Photocarrier recombination dynamics in perovskite CH3NH3PbI3 for solar cell applications. J. Am. Chem. Soc. 136, 11610–11613 (2014).10.1021/ja506624n ↗
22. Milot, R. L., Eperon, G. E., Snaith, H. J., Johnston, M. B. & Herz, L. M. Temperature-dependent charge-carrier dynamics in CH3NH3PbI3 perovskite thin films. Adv. Funct. Mater. 25, 6218–6227 (2015).10.1002/adfm.201502340 ↗
23. Bi, D. et al. Efficient luminescent solar cells based on tailored mixed-cation perovskites. Sci. Adv. 2, e1501170 (2016).10.1126/sciadv.1501170 ↗
24. Richter, J. M. et al. Enhancing photoluminescence yields in lead halide perovskites by photon recycling and light out-coupling. Nat. Commun. 7, 13941 (2016).10.1038/ncomms13941 ↗
25. Travis, W., Glover, E. N. K., Bronstein, H., Scanlon, D. O. & Palgrave, R. G. On the application of the tolerance factor to inorganic and hybrid halide perovskites: a revised system. Chem. Sci. 7, 4548–4556 (2016).10.1039/C5SC04845A ↗
26. Kim, G. et al. Impact of strain relaxation on performance of α-formamidinium lead iodide perovskite solar cells. Science 370, 108–112 (2020).10.1126/science.abc4417 ↗
27. Blöchl, P. E. Projector augmented-wave method. Phys. Rev. B 50, 17953–17979 (1994).10.1103/PhysRevB.50.17953 ↗
28. Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).10.1103/PhysRevB.54.11169 ↗
29. Monkhorst, H. J. & Pack, J. D. Special points for Brillouin-zone integrations. Phys. Rev. B 13, 5188–5192 (1976).10.1103/PhysRevB.13.5188 ↗
30. Frohna, K. et al. Inversion symmetry and bulk Rashba effect in methylammonium lead iodide perovskite single crystals. Nat. Commun. 9, 1829 (2018).10.1038/s41467-018-04212-w ↗
31. Baikie, T. et al. Synthesis and crystal chemistry of the hybrid perovskite (CH3NH3)PbI3 for solid-state sensitised solar cell applications. J. Mater. Chem. A 1, 5628–5641 (2013).10.1039/c3ta10518k ↗
32. Eperon, G. E. et al. Formamidinium lead trihalide: a broadly tunable perovskite for efficient planar heterojunction solar cells. Energy Environ. Sci. 7, 982–988 (2014).10.1039/c3ee43822h ↗
33. Han, Q. et al. Single crystal formamidinium lead iodide (FAPbI3): insight into the structural, optical, and electrical properties. Adv. Mater. 28, 2253–2258 (2016).10.1002/adma.201505002 ↗
34. Fabini, D. H. et al. Reentrant structural and optical properties and large positive thermal expansion in perovskite formamidinium lead iodide. Angew. Chem. Int. Ed. 55, 15392–15396 (2016).10.1002/anie.201609538 ↗
35. Freysoldt, C. et al. First-principles calculations for point defects in solids. Rev. Mod. Phys. 86, 253–305 (2014).10.1103/RevModPhys.86.253 ↗
36. Freysoldt, C., Neugebauer, J. & Van de Walle, C. G. Fully ab initio finite-size corrections for charged-defect supercell calculations. Phys. Rev. Lett. 102, 016402 (2009).10.1103/PhysRevLett.102.016402 ↗
37. Marston, C. C. & Balint-Kurti, G. G. The Fourier grid Hamiltonian method for bound state eigenvalues and eigenfunctions. J. Chem. Phys. 91, 3571–3576 (1989).10.1063/1.456888 ↗