Activating Organic Phosphorescence via Heavy Metal–π Interaction Induced Intersystem Crossing. Issue 51 (18th November 2022)

• Record Type: Journal Article
• Authors: Sun, Meng‐Jia; Anhalt, Olga; Sárosi, Menyhárt B.; Stolte, Matthias; Würthner, Frank
• Is Part Of: Advanced materials. Volume 34:Issue 51(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-11-18
• Subjects: cocrystallization -- naphthalene diimide -- phosphorescence -- platinum complexes -- triplet sensitization; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202207331
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Heavy‐atom‐containing clusters, nanocrystals, and other semiconductors can sensitize the triplet states of their surface‐bonded chromophores, but the energy loss, such as nonradiative deactivation, often prevents the synergistic light emission in their solid‐state coassemblies. Cocrystallization allows new combinations of molecules with complementary properties for achieving functionalities not available in single components. Here, the cocrystal formation that employs platinum(II) acetylacetonate (Pt(acac)2 ) as a triplet sensitizer and electron‐deficient 1, 4, 5, 8‐naphthalene diimides (NDIs) as organic phosphors is reported. The hybrid cocrystals exhibit room‐temperature phosphorescence confined in the low‐lying, long‐lived triplet state of NDIs with photoluminescence (PL) quantum yield (ΦPL ) exceeding 25% and a phosphorescence lifetime (τPh ) of 156 µs. This remarkable PL property benefits from the noncovalent electronic and spin–orbital coupling between the constituents. Abstract : A cocrystallization strategy is developed to enable efficient room‐temperature phosphorescence confined in the organic dye with a remarkable photoluminescence quantum yield of 25.1 ± 1%. This strategy to brighten the triplet state of organic chromophores may be quite general and open up a new avenue for designing innovative phosphorescent materials.