| Title: |
Design Principles for Narrow-Gap Hybrid Semiconductors: Insights from Viologen-Tin and Viologen-Lead Iodides |
| Authors: |
Reynolds, Robert, P; Persaud, Jessica, H; Volonakis, George; Torma, Andrew, J; Meza, Patricia, E; Kelly, Zek, E; Stoumpos, Constantinos, C; Dravid, Vinayak, P; Katan, Claudine; Mohite, Aditya, D; Kanatzidis, Mercouri, G |
| Contributors: |
Northwestern University Evanston; Rice University Houston; Institut des Sciences Chimiques de Rennes (ISCR); Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes); Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS); Department of Chemistry Heraklion; University of Crete Heraklion (UOC); Access to the HPC resources of TGCC under the Allocation Grant No. 2024 - A0150907682 made by GENCI. This work made use of the IMSERC Crystallography, NMR, and Physical Characterization facilities at Northwestern University, which have received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-2025633), and Northwestern University. Purchase of the Ag-microsource diffractometer used to obtain results included in this publication was supported by the Major Research Instrumentation Program from the National Science Foundation under the award CHE-1920248. This work made use of the EPIC facility of Northwestern University’s NUANCE Center, which has received support from the SHyNE Resource (NSF ECCS-2025633), the IIN, and Northwestern's MRSEC program (NSF DMR-2308691). This research was supported in part through the computational resources and staff contributions provided for the Quest high performance computing facility at Northwestern University which is jointly supported by the Office of the Provost, the Office for Research, and Northwestern University Information Technology.; ANR-23-CE09-0001,SURFIN,Surfaces et interfaces des nouveaux perovkites et perovskitoides.(2023); ANR-22-PETA-0015,MINOTAURE,Multimodal approach combining IN-situ, ex-situ and Operando CharacTerizAtion with SimUlations for Highly REliable Next Generation Photovoltaics(2022) |
| Source: |
ISSN: 0002-7863. |
| Publisher Information: |
CCSD; American Chemical Society |
| Publication Year: |
2025 |
| Subject Terms: |
Hybrid Tin Iodides; Hybrid Lead Iodides Viologens; Electronically Active Organics; Charge-Transfer; Infrared; Optoelectronics; Anomalous Band-bowing; Hybrid Lead Iodides; Viologens; Infrared Optoelectronics; [CHIM.MATE]Chemical Sciences/Material chemistry; [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat] |
| Description: |
International audience ; Hybrid metal halide semiconductors containing “electronically active” organics are an arising subclass of materials that derive remarkable emergent optical properties from blending organic orbitals with the photophysics of metal halide semiconductors. Although this subclass has been known for some time, the majority of reported compounds are lead halides, and there is a paucity of systematic studies investigating the influence of structure and composition on organic energy levels in these materials. Herein we report the first viologen tin hybrids to be published in the form of: HVSnI4 (HV = hydroviologen), MeVSn2I6 (MeV = methylviologen), and EtVSn2I6 (EtV = ethylviologen). These materials exhibit emergent electronic structures where charge-transfer from the inorganic lattice to viologen LUMO states results in optical gaps as narrow as 1.10eV. Through comparison of these compounds with their lead analogs and viologen iodide salts, we develop a systematic understanding of energy levels and lead/tin systems, which allows us to identify key chemical principles for future narrow-gap hybrid materials. We find that organic LUMO states in these materials are relatively immobile under the exchange of lead with tin but are strongly influenced by substituent choice, conformation, π-π stacking, and the polarizability of the inorganic lattice. We further study the energetic landscape of these materials in a set of lead/tin alloys (EtVPb2-xSnxI6) which do not exhibit the anomalous band-bowing typically associated with lead/tin alloys, providing a new point of evidence that this phenomenon generally relies on concomitant motions of the inorganic conduction and valence band. Photoresponse of HVSnI4 pressed pellet devices to 1064nm light establishes the potential of these materials for NIR optoelectronic applications. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.1021/jacs.5c05202 |
| Availability: |
https://hal.science/hal-05167303; https://hal.science/hal-05167303v1/document; https://hal.science/hal-05167303v1/file/Viologens-SnPb-MainText%20_HAL_Repository.pdf; https://doi.org/10.1021/jacs.5c05202 |
| Rights: |
http://hal.archives-ouvertes.fr/licences/copyright/ |
| Accession Number: |
edsbas.8D0B0ACD |
| Database: |
BASE |