51. enhancing spontaneous molecular ferroelectricity in mapbi3 by strain/doping-induced cell deformation: a first-principles study
Research Institute Affiliation: Agile - Sustainable Power and Energy Center (SPEC)
Faculty Advisor(s): Kesong Yang
Name: Yuheng Li
Grad Year: 2019
Hybrid perovskites have shown astonishing power conversion efficiencies owed to their remarkable absorber characteristics such as appropriate bandgap and long carrier lifetimes. However, fundamental reasons of the high efficiency compared to their inorganic counterpart are still unclear. And there has been continuing controversy about whether organic cations can form ferroelectric domains. Here our first-principles study addresses the spontaneous MA dipole alignment by studying energy barriers of basic rotation modes. Our results of different MA configurations in tetragonal phase demonstrate a weak spontaneous FE formation. We further explore enhancement approaches including compressive strain and doping of smaller anions. They share the common theoretical mechanism of cell deformation. We anticipate that enhanced ferroelectricity will greatly improve carrier lifetimes, and these theoretical enhancement principles will work as guidance for more reasonable composition design of hybrid perovskite solar cells.
Industry Application Area(s)
Energy/Clean technology | Materials | Semiconductor