TY - JOUR
T1 - Grain Size Influences Activation Energy and Migration Pathways in MAPbBr3 Perovskite Solar Cells
AU - McGovern, Lucie
AU - Koschany, Isabel
AU - Grimaldi, Gianluca
AU - Muscarella, Loreta A.
AU - Ehrler, Bruno
PY - 2021/3/11
Y1 - 2021/3/11
N2 - Ion migration in perovskite layers can significantly reduce the long-term stability of the devices. While perovskite composition engineering has proven an interesting tool to mitigate ion migration, many optoelectronic devices require a specific bandgap and thus require a specific perovskite composition. Here, we look at the effect of grain size to mitigate ion migration. We find that in MAPbBr3 solar cells prepared with grain sizes varying from 2 to 11 μm the activation energy for bromide ion migration increases from 0.17 to 0.28 eV. Moreover, we observe the appearance of a second bromide ion migration pathway for the devices with largest grain size, which we attribute to ion migration mediated by the bulk of the perovskite, as opposed to ion migration mediated by the grain boundaries. Together, these results suggest the beneficial nature of grain engineering for reduction of ion migration in perovskite solar cells.
AB - Ion migration in perovskite layers can significantly reduce the long-term stability of the devices. While perovskite composition engineering has proven an interesting tool to mitigate ion migration, many optoelectronic devices require a specific bandgap and thus require a specific perovskite composition. Here, we look at the effect of grain size to mitigate ion migration. We find that in MAPbBr3 solar cells prepared with grain sizes varying from 2 to 11 μm the activation energy for bromide ion migration increases from 0.17 to 0.28 eV. Moreover, we observe the appearance of a second bromide ion migration pathway for the devices with largest grain size, which we attribute to ion migration mediated by the bulk of the perovskite, as opposed to ion migration mediated by the grain boundaries. Together, these results suggest the beneficial nature of grain engineering for reduction of ion migration in perovskite solar cells.
U2 - 10.1021/acs.jpclett.1c00205
DO - 10.1021/acs.jpclett.1c00205
M3 - Article
SN - 1948-7185
VL - 12
SP - 2423
EP - 2428
JO - The journal of physical chemistry letters
JF - The journal of physical chemistry letters
IS - 9
ER -