Metal halide perovskites are rivaling established materials for thin film photovoltaics. Being able to tune interfacial alignment of energy levels may allow a further boost to the efficiency of perovskite optoelectronic devices. By using Density Functional Theory (DFT) modeling and experimental analysis, we show that the band edge energies of the prototypical MAPbI3 (MA = methylammonium) perovskite can in principle be varied by as much as 1 eV via postsynthetic chemical treatment. In particular, MAI-rich (PbI2-rich) surfaces induce an energy upshift (downshift) of the perovskite band energies, and this can either inhibit or favor hole transfer at the perovskite/HTL interface.
Energy Level Tuning at the MAPbI3 Perovskite/Contact Interface Using Chemical Treatment
Mosconi E.;Kelley S. O.;De Angelis F.
2019
Abstract
Metal halide perovskites are rivaling established materials for thin film photovoltaics. Being able to tune interfacial alignment of energy levels may allow a further boost to the efficiency of perovskite optoelectronic devices. By using Density Functional Theory (DFT) modeling and experimental analysis, we show that the band edge energies of the prototypical MAPbI3 (MA = methylammonium) perovskite can in principle be varied by as much as 1 eV via postsynthetic chemical treatment. In particular, MAI-rich (PbI2-rich) surfaces induce an energy upshift (downshift) of the perovskite band energies, and this can either inhibit or favor hole transfer at the perovskite/HTL interface.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.