TY - JOUR
T1 - Single-crystal-like optoelectronic-properties of MAPbI3 perovskite polycrystalline thin films
AU - Giesbrecht, Nadja
AU - Schlipf, Johannes
AU - Grill, Irene
AU - Rieder, Philipp
AU - Dyakonov, Vladimir
AU - Bein, Thomas
AU - Hartschuh, Achim
AU - Müller-Buschbaum, Peter
AU - Docampo, Pablo
N1 - Publisher Copyright:
© 2018 The Royal Society of Chemistry.
PY - 2018
Y1 - 2018
N2 - Our understanding of the crystallization process of hybrid halide perovskites has propelled the efficiency of state-of-the-art photovoltaic devices to over 22%. Further improvements to the performance will likely arise from reducing the number of grain boundaries. Here, current methods lead to grain sizes in the 1 micrometer range and the resulting optoelectronic properties suffer as compared to single-crystal materials. In this work, we introduce a new synthesis procedure with MAPbI3 leading to crystal sizes in the tens of microns range. This approach is based on the pre-crystallization of an intermediate phase (IP) based on the solid-state reaction of a lead-acetate trihydrate precursor mixture in a highly polar solvent. Beyond large grain sizes, the crystal orientation is also tightly controlled, leading to perovskite crystallites which remain perfectly aligned with the c-axis of the tetragonal structure parallel to the substrate as evidenced by grazing incidence wide angle X-ray scattering (GIWAXS). Furthermore, we demonstrate the high crystallinity and large grain size of the developed films via high-resolution transmission electron microscopy (HRTEM). The charge carrier mobilities are significantly improved with larger grain size and approach mobility values of about 40 cm2 V-1 s-1, moving toward the values observed for single crystals. We capitalize on the enhanced optoelectronic properties of the developed films by incorporating them into planar heterojunction solar cells which reach power conversion efficiencies of 18.5%, higher than MAPbI3-based device prepared from standard methods in a like-to-like comparison.
AB - Our understanding of the crystallization process of hybrid halide perovskites has propelled the efficiency of state-of-the-art photovoltaic devices to over 22%. Further improvements to the performance will likely arise from reducing the number of grain boundaries. Here, current methods lead to grain sizes in the 1 micrometer range and the resulting optoelectronic properties suffer as compared to single-crystal materials. In this work, we introduce a new synthesis procedure with MAPbI3 leading to crystal sizes in the tens of microns range. This approach is based on the pre-crystallization of an intermediate phase (IP) based on the solid-state reaction of a lead-acetate trihydrate precursor mixture in a highly polar solvent. Beyond large grain sizes, the crystal orientation is also tightly controlled, leading to perovskite crystallites which remain perfectly aligned with the c-axis of the tetragonal structure parallel to the substrate as evidenced by grazing incidence wide angle X-ray scattering (GIWAXS). Furthermore, we demonstrate the high crystallinity and large grain size of the developed films via high-resolution transmission electron microscopy (HRTEM). The charge carrier mobilities are significantly improved with larger grain size and approach mobility values of about 40 cm2 V-1 s-1, moving toward the values observed for single crystals. We capitalize on the enhanced optoelectronic properties of the developed films by incorporating them into planar heterojunction solar cells which reach power conversion efficiencies of 18.5%, higher than MAPbI3-based device prepared from standard methods in a like-to-like comparison.
UR - http://www.scopus.com/inward/record.url?scp=85043312069&partnerID=8YFLogxK
U2 - 10.1039/c7ta11190h
DO - 10.1039/c7ta11190h
M3 - Article
AN - SCOPUS:85043312069
SN - 2050-7488
VL - 6
SP - 4822
EP - 4828
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
IS - 11
ER -