TY - JOUR

T1 - Sky-blue thermally activated delayed fluorescence (TADF) based on Ag(i) complexes

T2 - Strong solvation-induced emission enhancement

AU - Artem'ev, Alexander V.

AU - Shafikov, Marsel Z.

AU - Schinabeck, Alexander

AU - Antonova, Olga V.

AU - Berezin, Alexey S.

AU - Bagryanskaya, Irina Yu

AU - Plusnin, Pavel E.

AU - Yersin, Hartmut

PY - 2019/11/1

Y1 - 2019/11/1

N2 - A new Ag(i) complex based on tris(2-pyridyl)phosphine (Py3P), [Ag2(Py3P)3(SCN)2], has been synthesized and chemically characterized. Theoretical calculations and photophysical investigations reveal thermally activated delayed fluorescence (TADF) coupled with outstanding solvato- A nd vapor-luminescent behavior. The parent complex [Ag2(Py3P)3(SCN)2] shows sky-blue TADF (λmax = 469 nm) at ambient temperature with a quantum yield of ΦPL = 16% and an emission decay time of 2.2 μs. Upon exposing the complex to CH2Cl2 or CHCl3 vapors, [Ag2(Py3P)3(SCN)2]·0.66CH2Cl2 and [Ag2(Py3P)3(SCN)2]·CHCl3 solvates are formed. This process is accompanied by a strong enhancement of the luminescence intensity. Both solvates also emit sky-blue TADF (λmax = 478-483 nm), but the emission quantum yield reaches ΦPL ≈ 70% at an emission decay time of 9-12 μs, depending on the solvent. According to DFT/TD-DFT computations, the observed TADF originates from a 1(M + X)LCT excited state. The experimentally determined ΔE(S1-T1) gap for [Ag2(Py3P)3(SCN)2]·0.66CH2Cl2 is relatively large and amounts to 1040 cm-1 (≈129 meV).

AB - A new Ag(i) complex based on tris(2-pyridyl)phosphine (Py3P), [Ag2(Py3P)3(SCN)2], has been synthesized and chemically characterized. Theoretical calculations and photophysical investigations reveal thermally activated delayed fluorescence (TADF) coupled with outstanding solvato- A nd vapor-luminescent behavior. The parent complex [Ag2(Py3P)3(SCN)2] shows sky-blue TADF (λmax = 469 nm) at ambient temperature with a quantum yield of ΦPL = 16% and an emission decay time of 2.2 μs. Upon exposing the complex to CH2Cl2 or CHCl3 vapors, [Ag2(Py3P)3(SCN)2]·0.66CH2Cl2 and [Ag2(Py3P)3(SCN)2]·CHCl3 solvates are formed. This process is accompanied by a strong enhancement of the luminescence intensity. Both solvates also emit sky-blue TADF (λmax = 478-483 nm), but the emission quantum yield reaches ΦPL ≈ 70% at an emission decay time of 9-12 μs, depending on the solvent. According to DFT/TD-DFT computations, the observed TADF originates from a 1(M + X)LCT excited state. The experimentally determined ΔE(S1-T1) gap for [Ag2(Py3P)3(SCN)2]·0.66CH2Cl2 is relatively large and amounts to 1040 cm-1 (≈129 meV).

KW - LIGHT-EMITTING-DIODES

KW - CU(I) COMPLEXES

KW - PHOTOLUMINESCENCE PROPERTIES

KW - COORDINATION POLYMERS

KW - SILVER(I) COMPLEXES

KW - TRIPLET EMITTERS

KW - DESIGN STRATEGY

KW - BASIS-SETS

KW - CU-I

KW - LUMINESCENCE

UR - http://www.scopus.com/inward/record.url?scp=85074638062&partnerID=8YFLogxK

U2 - 10.1039/c9qi01069f

DO - 10.1039/c9qi01069f

M3 - Article

AN - SCOPUS:85074638062

VL - 6

SP - 3168

EP - 3176

JO - Inorganic Chemistry Frontiers

JF - Inorganic Chemistry Frontiers

SN - 2052-1545

IS - 11

ER -