CrystEngComm, Год журнала: 2023, Номер 25(41), С. 5802 - 5809
Опубликована: Янв. 1, 2023
The presence of an ortho -linked substituent in pyrene can lead to steric hindrance on one side the plane, which prevents formation undesired interactions and promotes selective dimers a desired orientation.
Язык: Английский
Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(29)
Опубликована: Апрель 30, 2024
Abstract Purely organic molecules with room‐temperature phosphorescence (RTP) are potential luminescent materials high exciton utilization for light‐emitting diodes (OLEDs), but those exhibiting superb electroluminescence (EL) performances rarely explored, mainly due to their long lifetimes. Herein, a robust purely RTP molecule, 3,6‐bis(5‐phenylindolo[3,2‐a]carbazol‐12(5H)‐yl)‐xanthen‐9‐one (3,2‐PIC‐XT), is developed. The neat film of 3,2‐PIC‐XT shows strong green very short lifetime (2.9 μs) and photoluminescence quantum yield (72 %), behaviors balanced bipolar charge transport. nature validated by steady‐state transient absorption emission spectroscopies, the working mechanism deciphered theoretical simulation. Non‐doped multilayer OLEDs using thin films furnish an outstanding external efficiency (EQE) 24.91 % extremely low roll‐off (1.6 %) at 1000 cd m −2 . High‐performance non‐doped top‐emitting tandem also achieved, providing remarkable EQEs 24.53 42.50 %, respectively. Delightfully, simplified employing thick realized, furnishing excellent EQE 17.79 greatly enhanced operational lifetime. temperature‐dependent EL spectroscopies demonstrate electrophosphorescence attribute 3,2‐PIC‐XT. These best devices based on reported so far.
Язык: Английский
Процитировано
23
Deleted Journal, Год журнала: 2024, Номер 2(3)
Опубликована: Июль 23, 2024
Abstract Room‐temperature phosphorescence (RTP) materials have attracted significant attention due to their applications in various fields such as information storage and encryption, organic light‐emitting diode (OLED), sensing, lighting display, biological imaging, photodynamic therapy. Traditionally, RTP can be efficiently developed using inorganic systems with noble metals or rare earth elements. Recently, many efforts been devoted the development of based on small molecules. The strategies construct include hydrogen bonding, heavy atom effect, n –π* transitions, π–π stacking, donor–acceptor host–guest doping. Herein, we summarize recent examples molecules primarily focusing design properties. Moreover, promising OLED, well bio‐imaging phototherapy are discussed. challenges perspectives given provide inspiration toward future materials.
Язык: Английский
Процитировано
15
Advanced Optical Materials, Год журнала: 2024, Номер 12(12)
Опубликована: Янв. 15, 2024
Abstract In purely organic room‐temperature phosphorescence (RTP) materials, fluorescence radiative transitions generally compete against inter‐system crossing (ISC) to give fluorescence/phosphorescence dual emission. order achieve pure in RTP light‐emitting diodes (OLEDs), extended π‐conjugation is introduced into Se‐containing donors suppress the by symmetry excited state orbitals π–π * that cancel overlap of orbitals, and two novel nonaromatic amine donor containing orange emitters namely 2‐(benzo[c]phenoxaselenin‐10‐yl)‐4,6‐diphenyl‐1,3,5‐triazine (BPXSeDRZ) 2‐(dibenzo[a,c]phenoxaselenin‐11‐yl)‐4,6‐diphenyl‐1,3,5‐triazine (DBPXSeDRZ) are developed, both which exhibit efficient doped films thanks sufficient ISC transitions. As a result, high external quantum efficiencies 17.2% 17.9% respectively achieved for RTP‐OLEDs based on BPXSeDRZ DBPXSeDRZ first time, they also stable electro‐phosphorescence spectra wide driving voltage. Moreover, adopting as sensitizer harvest triplet excitons tetraphenyldibenzoperiflanthene conventional fluorescent emitter, efficiency sensitized red OLED can be elevated 10.1%, greatly expands potential applications metal‐free phosphors OLEDs.
Язык: Английский
Процитировано
14
The Journal of Physical Chemistry Letters, Год журнала: 2024, Номер 15(10), С. 2690 - 2696
Опубликована: Март 1, 2024
A cocrystallization strategy is used through incorporation of 1,2,4,5-tetracyanobenzene (TCNB) as an acceptor with halogen-substituent thioxanthone (TX) derivatives donors. The resulting cocrystals TT-R (R = H, F, Cl, Br, or I) transform the thermally activated delayed fluorescence emission in TT-H, TT-F, and TT-Cl to room-temperature phosphorescence TT-Br TT-I cocrystals. Definite crystal packing structures demonstrate a 1:1 alternative donor–acceptor stacking TT-H cocrystal, 2:1 TT-F cocrystals, separate donor transformation law can be revealed that increase atomic number from I, show structural aggregated TX-R molecules monomers dimers finally multimers. This work will facilitate understanding effect halogen substituents on structure luminescence properties
Язык: Английский
Процитировано
8
Chemical Science, Год журнала: 2024, Номер 15(28), С. 10784 - 10793
Опубликована: Янв. 1, 2024
Fast room-temperature phosphorescence with high quantum yields up to 38% in solution from metal-free organic 1,2-diketones is reported, along the mechanism and molecular design principles governing fast phosphorescence.
Язык: Английский
Процитировано
7
Chinese Chemical Letters, Год журнала: 2025, Номер unknown, С. 110837 - 110837
Опубликована: Янв. 1, 2025
Язык: Английский
Процитировано
1
Chemical Engineering Journal, Год журнала: 2025, Номер unknown, С. 159719 - 159719
Опубликована: Янв. 1, 2025
Язык: Английский
Процитировано
1
Chemistry - An Asian Journal, Год журнала: 2025, Номер unknown
Опубликована: Фев. 11, 2025
Abstract In this work, two novel types of bipolar phosphorescent host materials derived from triazine and indenocarbazole , which were 5‐(7‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)‐9,9‐dimethyl‐4b,8a‐dihydro‐9H‐fluoren‐2‐yl)‐7,7‐dimethyl‐5,7‐dihydroindeno[2,1‐b] carbazole ( m ‐TFFCz ) 5‐(7‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)‐9,9‐dimethyl‐4b,8a‐dihydro‐9H‐fluoren‐2‐yl)‐5H‐benzofuro[3,2‐c]carbazole ‐TFBFCz ). Both exhibit remarkable thermal stability, for example, their higher glass transition temperatures T g exceed 170 °C decomposition d above 400 °C. The have high triplet energy E 2.67 eV 2.75 eV, highest occupied molecular orbital (HOMO) lowest unoccupied (LUMO) are completely separated. addition, the red PhOLEDs based on m‐TFFCz m‐TFBFCz maximum external quantum efficiency (EQE max 20.31 % 25.40 %, time it takes a device to decay its initial brightness 95 original 8.96 h 102.63 h, respectively. Based results, synthesizing using triazines is viable design method high‐efficiency with great stability.
Язык: Английский
Процитировано
1
Journal of Electronic Materials, Год журнала: 2025, Номер unknown
Опубликована: Март 17, 2025
Язык: Английский
Процитировано
1
Advanced Optical Materials, Год журнала: 2023, Номер 12(9)
Опубликована: Ноя. 16, 2023
Circularly polarized luminescent (CPL) materials have significant promising applications in organic light-emitting diodes, asymmetric synthesis, and other fields. However, due to the instability of triplet-state excitons, how achieve an effective combination CPL with room-temperature phosphorescence (RTP) remains a formidable challenge. Here, simple feasible method for constructing polymer-based CPRTP is proposed by preparing chiral phosphorescent liquid crystals through copolymerization. A series RTP crystal copolymers are successfully synthesized copolymerizing monomer bearing cholesterol mesogen dibenzofuran chromophore. Due introduction mesogen, can form smectic C-phase crystals. Utilizing their selective reflection characteristic, efficient achieved, glum value up −1.6 × 10−2. In addition, both components exhibit properties show differences color lifetime. By changing composition copolymers, regulation achieved. As result, multicolor-tunable time-dependent prepared.
Язык: Английский
Процитировано
16