TY - JOUR

T1 - Design of Active Defects in Semiconductors: 3D Electron Diffraction Revealed Novel Organometallic Lead Bromide Phases Containing Ferrocene as Redox Switches

AU - Fillafer, Nicole

AU - Kuper, Henning

AU - Schaate, Andreas

AU - Locmelis, Sonja

AU - Becker, Joerg August

AU - Krysiak, Yaşar

AU - Polarz, Sebastian

N1 - Funding Information: The authors thank the German Research Foundation for funding (project PO 780/22-1). The authors thank Ute Kolb for access to the transmission electron microscope FEI Tecnai F30 S-TWIN at the EM Center in Mainz (EZMZ) of the university Mainz. The authors are grateful to Lukáš Palatinus for access to the TEM FEI Tecnai 20 at the Institute of Physics of the Czech Academy of Sciences. The authors thank Stefan Schupp for organizing the PESA measurements and Stephen Klimke for the Mößbauer analysis. The authors thank the LNQE Research Center for the use of the XPS. Open access funding enabled and organized by Projekt DEAL. Funding Information: The authors thank the German Research Foundation for funding (project PO 780/22‐1). The authors thank Ute Kolb for access to the transmission electron microscope FEI Tecnai F30 S‐TWIN at the EM Center in Mainz (EZMZ) of the university Mainz. The authors are grateful to Lukáš Palatinus for access to the TEM FEI Tecnai 20 at the Institute of Physics of the Czech Academy of Sciences. The authors thank Stefan Schupp for organizing the PESA measurements and Stephen Klimke for the Mößbauer analysis. The authors thank the LNQE Research Center for the use of the XPS.

PY - 2022/6/8

Y1 - 2022/6/8

N2 - Once the optical, electronic, or photocatalytic properties of a semiconductor are set by adjusting composition, crystal phase, and morphology, one cannot change them anymore, respectively, on demand. Materials enabling postsynthetic and reversible switching of features such as absorption coefficient, bandgap, or charge carrier dynamics are highly desired. Hybrid perovskites facilitate exceptional possibilities for progress in the field of smart semiconductors because active organic molecules become an integral constituent of the crystalline structure. This paper reports the integration of ferrocene ligands into semiconducting 2D phases based on lead bromide. The complex crystal structures of the resulting, novel ferrovskite (≃ ferrocene perovskite) phases are determined by 3D electron diffraction. The ferrocene ligands exhibit strong structure-directing effects on the 2D hybrid phases, which is why the formation of exotic types of face- and edge-sharing lead bromide octahedra is observed. The bandgap of the materials ranges from 3.06 up to 3.51 eV, depending on the connectivity of the octahedra. By deploying the redox features of ferrocene, one can create defect states or even a defect band leading to control over the direction of exciton migration and energy transport in the semiconductor, enabling fluorescence via indirect to direct gap transition.

AB - Once the optical, electronic, or photocatalytic properties of a semiconductor are set by adjusting composition, crystal phase, and morphology, one cannot change them anymore, respectively, on demand. Materials enabling postsynthetic and reversible switching of features such as absorption coefficient, bandgap, or charge carrier dynamics are highly desired. Hybrid perovskites facilitate exceptional possibilities for progress in the field of smart semiconductors because active organic molecules become an integral constituent of the crystalline structure. This paper reports the integration of ferrocene ligands into semiconducting 2D phases based on lead bromide. The complex crystal structures of the resulting, novel ferrovskite (≃ ferrocene perovskite) phases are determined by 3D electron diffraction. The ferrocene ligands exhibit strong structure-directing effects on the 2D hybrid phases, which is why the formation of exotic types of face- and edge-sharing lead bromide octahedra is observed. The bandgap of the materials ranges from 3.06 up to 3.51 eV, depending on the connectivity of the octahedra. By deploying the redox features of ferrocene, one can create defect states or even a defect band leading to control over the direction of exciton migration and energy transport in the semiconductor, enabling fluorescence via indirect to direct gap transition.

KW - ferrocene materials

KW - hybrid perovskites

KW - MicroED

KW - molecular switches

KW - semiconductors

UR - http://www.scopus.com/inward/record.url?scp=85125960261&partnerID=8YFLogxK

U2 - 10.1002/adfm.202201126

DO - 10.1002/adfm.202201126

M3 - Article

AN - SCOPUS:85125960261

VL - 32

JO - Advanced functional materials

JF - Advanced functional materials

SN - 1616-301X

IS - 24

M1 - 2201126

ER -