Bandgap tunability of lead mixed halide perovskites (LMHPs) is a crucial characteristic for versatile optoelectronic applications. Nevertheless, LMHPs show the formation of iodide-rich (I-rich) phase under illumination, which destabilizes the semiconductor bandgap and impedes their exploitation. Here, it is shown that how I2 , photogenerated upon charge carrier trapping at iodine interstitials in LMHPs, can promote the formation of I-rich phase. I2 can react with bromide (Br- ) in the perovskite to form a trihalide ion I2 Br- (Iδ- -Iδ+ -Brδ- ), whose negatively charged iodide (Iδ- ) can further exchange with another lattice Br- to form the I-rich phase. Importantly, it is observed that the effectiveness of the process is dependent on the overall stability of the crystalline perovskite structure. Therefore, the bandgap instability in LMHPs is governed by two factors, i.e., the density of native defects leading to I2 production and the Br- binding strength within the crystalline unit. Eventually, this study provides rules for the design of chemical composition in LMHPs to reach their full potential for optoelectronic devices.

How Photogenerated I2 Induces I-Rich Phase Formation in Lead Mixed Halide Perovskites / Zhou Y.; van Laar S.C.W.; Meggiolaro D.; Gregori L.; Martani S.; Heng J.Y.; Datta K.; Jiménez-López J.; Wang F.; Wong E.L.; Poli I.; Treglia A.; Cortecchia D.; Prato M.; Kobera L.; Gao F.; Zhao N.; Janssen R.A.J.; De Angelis F.; Petrozza A.. - In: ADVANCED MATERIALS. - ISSN 0935-9648. - ELETTRONICO. - 36:(2024), pp. 2305567.1-2305567.12. [10.1002/adma.202305567]

How Photogenerated I2 Induces I-Rich Phase Formation in Lead Mixed Halide Perovskites

Cortecchia D.;
2024

Abstract

Bandgap tunability of lead mixed halide perovskites (LMHPs) is a crucial characteristic for versatile optoelectronic applications. Nevertheless, LMHPs show the formation of iodide-rich (I-rich) phase under illumination, which destabilizes the semiconductor bandgap and impedes their exploitation. Here, it is shown that how I2 , photogenerated upon charge carrier trapping at iodine interstitials in LMHPs, can promote the formation of I-rich phase. I2 can react with bromide (Br- ) in the perovskite to form a trihalide ion I2 Br- (Iδ- -Iδ+ -Brδ- ), whose negatively charged iodide (Iδ- ) can further exchange with another lattice Br- to form the I-rich phase. Importantly, it is observed that the effectiveness of the process is dependent on the overall stability of the crystalline perovskite structure. Therefore, the bandgap instability in LMHPs is governed by two factors, i.e., the density of native defects leading to I2 production and the Br- binding strength within the crystalline unit. Eventually, this study provides rules for the design of chemical composition in LMHPs to reach their full potential for optoelectronic devices.
2024
How Photogenerated I2 Induces I-Rich Phase Formation in Lead Mixed Halide Perovskites / Zhou Y.; van Laar S.C.W.; Meggiolaro D.; Gregori L.; Martani S.; Heng J.Y.; Datta K.; Jiménez-López J.; Wang F.; Wong E.L.; Poli I.; Treglia A.; Cortecchia D.; Prato M.; Kobera L.; Gao F.; Zhao N.; Janssen R.A.J.; De Angelis F.; Petrozza A.. - In: ADVANCED MATERIALS. - ISSN 0935-9648. - ELETTRONICO. - 36:(2024), pp. 2305567.1-2305567.12. [10.1002/adma.202305567]
Zhou Y.; van Laar S.C.W.; Meggiolaro D.; Gregori L.; Martani S.; Heng J.Y.; Datta K.; Jiménez-López J.; Wang F.; Wong E.L.; Poli I.; Treglia A.; Cortecchia D.; Prato M.; Kobera L.; Gao F.; Zhao N.; Janssen R.A.J.; De Angelis F.; Petrozza A.
File in questo prodotto:
File Dimensione Formato  
Advanced Materials - 2023 - Zhou - How Photogenerated I2 Induces I‐Rich Phase Formation in Lead Mixed Halide Perovskites.pdf

accesso aperto

Descrizione: Main Article
Tipo: Versione (PDF) editoriale
Licenza: Licenza per Accesso Aperto. Creative Commons Attribuzione - Non commerciale - Non opere derivate (CCBYNCND)
Dimensione 3.07 MB
Formato Adobe PDF
3.07 MB Adobe PDF Visualizza/Apri
adma202305567-sup-0001-suppmat.pdf

accesso aperto

Descrizione: Supporting Information
Tipo: File Supplementare
Licenza: Licenza per Accesso Aperto. Creative Commons Attribuzione - Non commerciale - Non opere derivate (CCBYNCND)
Dimensione 2.19 MB
Formato Adobe PDF
2.19 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/956606
Citazioni
  • ???jsp.display-item.citation.pmc??? 0
  • Scopus 3
  • ???jsp.display-item.citation.isi??? 2
social impact