ION MIGRATION MODEL IN PEROVSKITE SOLAR CELLS

Gulxayot Xolyigitova Sulaymanovna

Authors

Gulxayot Xolyigitova Sulaymanovna Andijon state technical institute, assistant

Keywords:

perovskite solar cells; ion migration; drift–diffusion model; ionic defects; hysteresis effect; charge transport; defect engineering; hybrid perovskites; photovoltaic devices.

Abstract

Ion migration in perovskite solar cells critically influences device performance, stability, and hysteresis behavior. This study presents a comprehensive model describing ionic transport mechanisms within hybrid organic–inorganic perovskite structures, focusing on vacancy-assisted migration of halide ions and mobile cations under internal electric fields. The model integrates drift–diffusion equations with electrostatic coupling to account for time-dependent ion redistribution and its impact on charge carrier dynamics. Particular attention is given to the interaction between ionic defects and electronic processes, including recombination and band bending at interfaces. Numerical simulations reveal that ion accumulation at selective contacts leads to transient photovoltaic responses and long-term degradation pathways. The proposed framework provides insights into mitigating hysteresis and enhancing operational stability through material engineering and interface optimization. These findings contribute to the fundamental understanding of ion–electron coupling and offer practical strategies for improving the efficiency and durability of next-generation perovskite photovoltaic devices.

References

NREL, “Best Research-Cell Efficiency Chart,” National Renewable Energy Laboratory, 2023.

S. D. Stranks and H. J. Snaith, “Metal-halide perovskites for photovoltaic and light-emitting devices,” Nature Nanotechnology, vol. 10, pp. 391–402, 2015.

J. Maier, “Ionic conduction in space charge regions,” Progress in Solid State Chemistry, vol. 23, pp. 171–263, 1995.

A. Walsh et al., “Self-regulation mechanism for charged point defects in hybrid halide perovskites,” Angewandte Chemie, vol. 54, pp. 1791–1794, 2015.

H.-S. Kim and N.-G. Park, “Parameters affecting I–V hysteresis of CH3_33NH3_33PbI3_33 perovskite solar cells: Effects of perovskite crystal size and mesoporous TiO2_22 layer,” Journal of Physical Chemistry Letters, vol. 5, pp. 2927–2934, 2014.

Y. Yuan and J. Huang, “Ion migration in organometal trihalide perovskite and its impact on photovoltaic efficiency and stability,” Accounts of Chemical Research, vol. 49, pp. 286–293, 2016.

E. Mosconi, J. M. Azpiroz, and F. De Angelis, “Ab initio molecular dynamics simulations of methylammonium lead iodide perovskite degradation by water,” Chemistry of Materials, vol. 27, pp. 4885–4892, 2015.

W. Tress, “Metal halide perovskites as mixed electronic–ionic conductors: Challenges and opportunities—from hysteresis to memristivity,” Journal of Physical Chemistry Letters, vol. 8, pp. 3106–3114, 2017.