Influence of Perovskite Morphology on Slow and Fast Charge Transport and Hysteresis in the Perovskite Solar Cells.
We have investigated the influence of perovskite morphology on slow and fast charge transport in the perovskite solar cells. Solar cells with different perovskite cuboid sizes (50-300 nm) have been fabricated using various methylammonium iodide concentrations. Both the low-frequency capacitance and hysteresis are maximum for the cell with the largest perovskite grains (300 nm). The low-frequency capacitance is about three orders of magnitude greater than the intermediate frequency capacitance, indicating the great role of ions on the slow responses and hysteresis. The measurement of open-circuit voltage decay indicates that for the large grains of 300 nm up to 70% of Vocremains across the cell, even after passing ∼40 s. Such a long time Vocdecay demonstrates the large accumulation of the ions at the perovskite interfaces with electron and hole transport layers, which conduct slow redistribution of the charges after the light is turned off.
Department of Physics, Tarbiat Modares University , P.O. Box 14115-175, Tehran, Iran.
Nasim
N
Mohammadian
Department of Physics, Tarbiat Modares University , P.O. Box 14115-175, Tehran, Iran.
Ahmad
A
Moshaii
School of Electrical and Computer Engineering, Tarbiat Modares University , P.O. Box 14115-194, Tehran, Iran.
Amirhossein
A
Alizadeh
Department of Physics, Tarbiat Modares University , P.O. Box 14115-175, Tehran, Iran.
Saba
S
Gharibzadeh
Institute for Nanoscience and Nanotechnology, Sharif University of Technology , P.O. Box 14588-89694, Tehran, Iran.
Raheleh
R
Mohammadpour