title: Broadband Emission in Two-Dimensional Hybrid Perovskites: The Role of Structural Deformation.
abstract: Only a selected group of two-dimensional (2D) lead-halide perovskites shows a peculiar broad-band photoluminescence. Here we show that the structural distortions of the perovskite lattice can determine the defectivity of the material by modulating the defect formation energies. By selecting and comparing two archetype systems, namely, (NBT)2PbI4and (EDBE)PbI4perovskites (NBT = n-butylammonium and EDBE = 2,2-(ethylenedioxy)bis(ethylammonium)), we find that only the latter, subject to larger deformation of the Pb-X bond length and X-Pb-X bond angles, sees the formation of VFcolor centers whose radiative decay ultimately leads to broadened PL. These findings highlight the importance of structural engineering to control the optoelectronic properties of this class of soft materials.
authors.affiliation: Interdisciplinary Graduate School, Energy Research Institute @ NTU(ERI@N), Nanyang Technological University , 639798 Singapore.|Centre for Nano Science and Technology (CNST@PoliMi), Istituto Italiano di Tecnologia , via Pascoli 70/3, Milan 20133, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Cortecchia
authors.affiliation: Centre for Nano Science and Technology (CNST@PoliMi), Istituto Italiano di Tecnologia , via Pascoli 70/3, Milan 20133, Italy.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Neutzner
authors.affiliation: Centre for Nano Science and Technology (CNST@PoliMi), Istituto Italiano di Tecnologia , via Pascoli 70/3, Milan 20133, Italy.
authors.forename: Ajay Ram
authors.initials: AR
authors.lastname: Srimath Kandada
authors.affiliation: Istituto CNR di Scienze e Tecnologie Molecolari, c/o Dipartimento di Chimica, Università di Perugia , Perugia I-06123, Italy.|CompuNet, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Mosconi
authors.affiliation: Istituto CNR di Scienze e Tecnologie Molecolari, c/o Dipartimento di Chimica, Università di Perugia , Perugia I-06123, Italy.|CompuNet, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Meggiolaro
authors.affiliation: Istituto CNR di Scienze e Tecnologie Molecolari, c/o Dipartimento di Chimica, Università di Perugia , Perugia I-06123, Italy.|CompuNet, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: De Angelis
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , 637371 Singapore.
authors.forename: Cesare
authors.initials: C
authors.lastname: Soci
authors.affiliation: Centre for Nano Science and Technology (CNST@PoliMi), Istituto Italiano di Tecnologia , via Pascoli 70/3, Milan 20133, Italy.
authors.forename: Annamaria
authors.identifier: 0000-0001-6914-4537
authors.initials: A
authors.lastname: Petrozza