TY - JOUR
T1 - Effects of Nonhydrostatic Stress on Structural and Optoelectronic Properties of Methylammonium Lead Bromide Perovskite
AU - Zhang, Rong
AU - Cai, Weizhao
AU - Bi, Tiange
AU - Zarifi, Niloofar
AU - Terpstra, Tyson
AU - Zhang, Chuang
AU - Verdeny, Z. Valy
AU - Zurek, Eva
AU - Deemyad, Shanti
N1 - Publisher Copyright:
© 2017 American Chemical Society. This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.
PY - 2017/8/3
Y1 - 2017/8/3
N2 - We report synchrotron X-ray diffraction, photoconductivity, and photoluminescence investigations of methylammonium-lead-bromide (MAPbBr3) under various stress conditions, supported by density-functional-theory (DFT) calculations. The properties of MAPbBr3 show substantial dependence on the hydrostatic conditions. While nonhydrostatic compression of MAPbBr3 leads to amorphization above 2.4 GPa, under quasi-hydrostatic (Ar) and hydrostatic (He) pressure, the sample remains in crystalline phases. A sequence of phase transitions between two cubic phases and orthorhombic Pnma phase is observed when using Ar, or no pressure-transmitting-medium (PTM). In helium-PTM only transitions between the two cubic structures and a new isostructural phase transition with a large volume collapse to a third cubic-phase at 2.7 GPa was observed. The photoluminescence measurements indicate a pressure-induced band gap-narrowing in the cubic phase I, and a blue-shift in the orthorhombic structure. DFT calculations illustrate that the dynamics of the organic molecules and the inorganic lattice, coupled via the N?H???Br hydrogen-bonding interactions, affect the Pb?Br distance and the bandgap evolution under pressure.
AB - We report synchrotron X-ray diffraction, photoconductivity, and photoluminescence investigations of methylammonium-lead-bromide (MAPbBr3) under various stress conditions, supported by density-functional-theory (DFT) calculations. The properties of MAPbBr3 show substantial dependence on the hydrostatic conditions. While nonhydrostatic compression of MAPbBr3 leads to amorphization above 2.4 GPa, under quasi-hydrostatic (Ar) and hydrostatic (He) pressure, the sample remains in crystalline phases. A sequence of phase transitions between two cubic phases and orthorhombic Pnma phase is observed when using Ar, or no pressure-transmitting-medium (PTM). In helium-PTM only transitions between the two cubic structures and a new isostructural phase transition with a large volume collapse to a third cubic-phase at 2.7 GPa was observed. The photoluminescence measurements indicate a pressure-induced band gap-narrowing in the cubic phase I, and a blue-shift in the orthorhombic structure. DFT calculations illustrate that the dynamics of the organic molecules and the inorganic lattice, coupled via the N?H???Br hydrogen-bonding interactions, affect the Pb?Br distance and the bandgap evolution under pressure.
UR - https://www.scopus.com/pages/publications/85026823200
U2 - 10.1021/acs.jpclett.7b01367
DO - 10.1021/acs.jpclett.7b01367
M3 - Letter
C2 - 28691486
AN - SCOPUS:85026823200
SN - 1948-7185
VL - 8
SP - 3457
EP - 3465
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 15
ER -