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Title: Stabilizing 2D Pt‐Based Halide Perovskites via Solvent Lone Pair Donation
Abstract Platinum‐based halide perovskites exhibit promising optoelectronic properties along with merits of low‐temperature processing and stability. Current research on Pt halide perovskites is limited to 0D A2BX6structure as the ABX33D structure is thermodynamically unstable. Herein, the study reports the stabilization of the ABX3structure into a 2D layered phase, CsPtI3(DMSO), that is stable up to 181.5 °C. The 2D phase shows an excitonic peak at the absorption edge of 600 nm, indicating quantum confinement. It also exhibits a large Stokes shift due to intersystem crossing (ISC), with a quenched singlet excitonic fluorescence at 610 nm and strong triplet emission at 852 nm. Pt(II) co‐ordinates with dimethyl sulfoxide (DMSO) via σ‐donation of S lone‐pair electrons and π‐ back donation from Pt to S, stabilizing CsPtI3(DMSO) layered structure. The strong electronic interaction between DMSO and Pt(II) and orbital mixing lead to spin‐orbit‐coupling, facilitating ISC and singlet‐to‐triplet exciton energy transfer. The interaction of Pt and DMSO is further confirmed by addition of thioacetamide (TAA), a strong S‐donor, which retards the formation of 2D layered structure, and directly results in Cs2PtI6and Pt.  more » « less
Award ID(s):
2342007
PAR ID:
10551821
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Optical Materials
Volume:
13
Issue:
6
ISSN:
2195-1071
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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