TY  - JOUR
A1  - Wu, Zhu
A1  - Dinkelbach, Fabian
A1  - Kerner, Florian
A1  - Friedrich, Alexandra
A1  - Ji, Lei
A1  - Stepanenko, Vladimir
A1  - Würthner, Frank
A1  - Marian, Christel M.
A1  - Marder, Todd B.
T1  - Aggregation-Induced Dual Phosphorescence from (o-Bromophenyl)-Bis(2,6-Dimethylphenyl)Borane at Room Temperature
JF  - Chemistry—A European Journal
N2  - Designing highly efficient purely organic phosphors at room temperature remains a challenge because of fast non-radiative processes and slow intersystem crossing (ISC) rates. The majority of them emit only single component phosphorescence. Herein, we have prepared 3 isomers (o, m, p-bromophenyl)-bis(2,6-dimethylphenyl)boranes. Among the 3 isomers (o-, m- and p-BrTAB) synthesized, the ortho-one is the only one which shows dual phosphorescence, with a short lifetime of 0.8 ms and a long lifetime of 234 ms in the crystalline state at room temperature. Based on theoretical calculations and crystal structure analysis of o-BrTAB, the short lifetime component is ascribed to the T\(^M_1\) state of the monomer which emits the higher energy phosphorescence. The long-lived, lower energy phosphorescence emission is attributed to the T\(^A_1\) state of an aggregate, with multiple intermolecular interactions existing in crystalline o-BrTAB inhibiting nonradiative decay and stabilizing the triplet states efficiently.
KW  - AIE
KW  - luminescence
KW  - phosphorescence
KW  - triarylborane
KW  - triplet
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-318297
VL  - 28
IS  - 30
ER  - 
TY  - JOUR
A1  - Wu, Zhu
A1  - Nitsch, Jörn
A1  - Marder, Todd B.
T1  - Persistent room-temperature phosphorence from purely organic molecules and multi-component systems
JF  - Advanced Optical Materials
N2  - Recently, luminophores showing efficient room-temperature phosphorescence (RTP) have gained tremendous interest due to their numerous applications. However, most phosphors are derived from transition metal complexes because of their intrinsic fast intersystem crossing (ISC) induced by strong spin–orbit coupling (SOC) constants of the heavy metal. 

Metal-free RTP materials are rare and have become a promising field because they are inexpensive and environmentally friendly. This review summarizes organic molecular materials with long triplet lifetimes at room temperature from the perspective of whether they stem from a molecular or multi-component system. Among purely organic phosphors, heteroatoms are usually introduced into the backbone in order to boost the singlet–triplet ISC rate constant. 

In multi-component systems, useful strategies such as host–guest, polymer matrix, copolymerization, and supramolecular assembly provide a rigid matrix to restrict nonradiative pathways thus realizing ultralong RTP.
KW  - inorganic chemistry
KW  - non-radiative  decay
KW  - polymer matrix
KW  - intersystem  crossing
KW  - luminescence
KW  - photophysics
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-256415
VL  - 9
IS  - 20
ER  -