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1.
Xuan Wang Nan Gan Mingxing Gu Kun Ling Chaoqun Ma Huili Ma Wei Yao Yujian Zhang Huifang Shi Zhongfu An Wei Huang 《中国化学快报》2019,30(11):1935-1938
Ultralong organic phosphorescent materials have invoked considerable attention for their great potential in sensing, data encryption, information anti-counterfeiting and so forth. However, effective ways to achieve highly efficient ultralong organic phosphorescence (UOP) in metal-free organic materials remain a great challenge. Herein, we designed three isomers based on asymmetric triazines with various bromine substituted positions. Impressively, phosphorescence efficiency of p-BrAT in solid state can reach up to 9.7% with a long lifetime of 386 ms, which was one of the highest efficient UOP materials reported so far. Theoretical calculations further demonstrated that para-substitution exhibited the most effective radiative transition for triplet excitons. These results will provide an effective approach to achieving highly efficient UOP materials. 相似文献
2.
Zhan Yang Chao Xu Wenlang Li Zhu Mao Xiangyu Ge Qiuyi Huang Huangjun Deng Juan Zhao Feng Long Gu Yi Zhang Zhenguo Chi 《Angewandte Chemie (International ed. in English)》2020,59(40):17451-17455
Ultralong organic phosphorescence (UOP) has attracted increasing attention due to its potential applications in optoelectronics, bioelectronics, and security protection. However, achieving UOP with high quantum efficiency (QE) over 20 % is still full of challenges due to intersystem crossing (ISC) and fast non‐radiative transitions in organic molecules. Here, we present a novel strategy to enhance the QE of UOP materials by modulating intramolecular halogen bonding via structural isomerism. The QE of CzS2Br reaches up to 52.10 %, which is the highest afterglow efficiency reported so far. The crucial reason for the extraordinary QE is intramolecular halogen bonding, which can not only effectively enhance ISC by promoting spin–orbit coupling, but also greatly confine motions of excited molecules to restrict non‐radiative pathways. This work provides a reasonable strategy to develop highly efficient UOP materials for practical applications. 相似文献
3.
Zhan Yang Dr. Chao Xu Wenlang Li Dr. Zhu Mao Xiangyu Ge Qiuyi Huang Huangjun Deng Prof. Juan Zhao Prof. Feng Long Gu Prof. Yi Zhang Prof. Zhenguo Chi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(40):17604-17608
Ultralong organic phosphorescence (UOP) has attracted increasing attention due to its potential applications in optoelectronics, bioelectronics, and security protection. However, achieving UOP with high quantum efficiency (QE) over 20 % is still full of challenges due to intersystem crossing (ISC) and fast non-radiative transitions in organic molecules. Here, we present a novel strategy to enhance the QE of UOP materials by modulating intramolecular halogen bonding via structural isomerism. The QE of CzS2Br reaches up to 52.10 %, which is the highest afterglow efficiency reported so far. The crucial reason for the extraordinary QE is intramolecular halogen bonding, which can not only effectively enhance ISC by promoting spin–orbit coupling, but also greatly confine motions of excited molecules to restrict non-radiative pathways. This work provides a reasonable strategy to develop highly efficient UOP materials for practical applications. 相似文献
4.
Yanni Zhang Jianfeng Zhao Caixia Zhu Lifang Bian Huifang Shi Shiming Zhang Huili Ma Wei Huang 《中国化学快报》1990,30(11):1974-1978
Regioisomerism effect was disclosed on optimizing ultralongorganic phosphorescence life times of three crystalline dicarbazol-9-yl pyrazine-based regioisomers (p-DCzP,m-DCzP,and o-DCzP) with para-,meta-, and ortho-convergent substitutions.It is revealed that regioisomerism effect could be an effective strategy for the deep understanding of UOP materials. 相似文献
5.
He Wang Huifang Shi Wenpeng Ye Xiaokang Yao Qian Wang Chaomin Dong Wenyong Jia Huili Ma Suzhi Cai Kaiwei Huang Lishun Fu Yanyun Zhang Jiahuan Zhi Long Gu Yanli Zhao Zhongfu An Wei Huang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(52):18952-18958
Amorphous purely organic phosphorescence materials with long‐lived and color‐tunable emission are rare. Herein, we report a concise chemical ionization strategy to endow conventional poly(4‐vinylpyridine) (PVP) derivatives with ultralong organic phosphorescence (UOP) under ambient conditions. After the ionization of 1,4‐butanesultone, the resulting PVP‐S phosphor showed a UOP lifetime of 578.36 ms, which is 525 times longer than that of PVP polymer itself. Remarkably, multicolor UOP emission ranging from blue to red was observed with variation of the excitation wavelength, which has rarely been reported for organic luminescent materials. This finding not only provides a guideline for developing amorphous polymers with UOP properties, but also extends the scope of room‐temperature phosphorescence (RTP) materials for practical applications in photoelectric fields. 相似文献
6.
Hydrogen‐Bonded Organic Aromatic Frameworks for Ultralong Phosphorescence by Intralayer π–π Interactions 下载免费PDF全文
Zaiyong Zhang Xuan Wang Dr. Huili Ma Nan Gan Qi Wu Zhichao Cheng Kun Ling Mingxing Gu Chaoqun Ma Long Gu Prof. Zhongfu An Prof. Wei Huang 《Angewandte Chemie (International ed. in English)》2018,57(15):4005-4009
Ultralong organic phosphorescence (UOP) based on metal‐free porous materials is rarely reported owing to rapid nonradiative transition under ambient conditions. In this study, hydrogen‐bonded organic aromatic frameworks (HOAFs) with different pore sizes were constructed through strong intralayer π–π interactions to enable ultralong phosphorescence in metal‐free porous materials under ambient conditions for the first time. Impressively, yellow UOP with a lifetime of 79.8 ms observed for PhTCz‐1 lasted for several seconds upon ceasing the excitation. For PhTCz‐2 and PhTCz‐3, on account of oxygen‐dependent phosphorescence quenching, UOP could only be visualized in N2, thus demonstrating the potential of phosphorescent porous materials for oxygen sensing. This result not only outlines a principle for the design of new HOFs with high thermal stability, but also expands the scope of metal‐free luminescent materials with the property of UOP. 相似文献
7.
Wenyong Jia Qian Wang Prof. Huifang Shi Prof. Zhongfu An Prof. Wei Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(20):4437-4448
Ultralong organic phosphorescence (UOP) of metal-free organic materials has received considerable attention recently owing to their long-lived emission lifetimes, and the fact that they present an attractive alternative to persistent luminescence in inorganic phosphors. Enormous research effort has been devoted on improving UOP performance in metal-free organic phosphors by promoting the intersystem crossing (ISC) process and suppressing the non-radiative decay of triplet state excitons. This minireview summarizes the recent advances in the rational approaches for manipulating the UOP properties of small molecular crystals, such as phosphorescence lifetime, efficiency, and emission colors. Finally, the present challenges and future development of this field are proposed. This review will provide a guideline to rationally design more advanced metal-free organic phosphorescence materials for potential applications. 相似文献
8.
Yanni Zhang Jianfeng Zhao Caixia Zhu Lifang Bian Huifang Shi Shiming Zhang Huili Ma Wei Huang 《中国化学快报》2019,30(11):1974-1978
Organic phosphorescence materials demonstrate potential optoelectronic applications due to their remarkably ultralong organic phosphorescence (UOP) lifetime and abundant optical characteristics prior to the fluorescence materials. For a better insight into the intrinsic relationship among regioisomeric molecules, crystalline interactions, and phosphorescence properties, three crystalline dicarbazol-9-yl pyrazine-based regioisomers with para-, meta-, and ortho-convergent substitutions (p-DCzP, m-DCzP, and o-DCzP) were designed and presented gradually increased UOP lifetimes prolonging from 63.14, 127.93 to 350.46 ms, respectively, due to the regioisomerism effect (RIE) which would be an effective strategy for better understanding of structure-property of UOP materials. 相似文献
9.
Kun Ling Dr. Huili Ma Suzhi Cai Lulu Song Chaoqun Ma Prof. Hai Li Prof. Guichuan Xing Prof. Xiaochun Hang Dr. Jiewei Li Yaru Gao Dr. Wei Yao Prof. Zhigang Shuai Prof. Zhongfu An Prof. Xiaogang Liu Prof. Wei Huang 《Angewandte Chemie (International ed. in English)》2018,57(28):8425-8431
Smart materials with ultralong phosphorescence are rarely investigated and reported. Herein we report on a series of molecules with unique dynamic ultralong organic phosphorescence (UOP) features, enabled by manipulating intermolecular interactions through UV light irradiation. Our experimental data reveal that prolonged irradiation of single‐component organic phosphors of PCzT, BCzT, and FCzT under ambient conditions can activate UOP with emission lifetimes spanning from 1.8 to 1330 ms. These phosphors can also be deactivated back to their original states with short‐lived phosphorescence by UV irradiation for 3 h at room temperature or through thermal treatment. Additionally, the dynamic UOP was applied successfully for a visual anti‐counterfeiting application. These findings may provide unique insight into dynamic molecular motion for optical processing and expand the scope of smart‐response materials for broader applications. 相似文献
10.
Nan Gan Xuan Wang Huili Ma Anqi Lv He Wang Qian Wang Mingxing Gu Suzhi Cai Yanyun Zhang Lishun Fu Meng Zhang Chaomin Dong Wei Yao Huifang Shi Zhongfu An Wei Huang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(40):14278-14283
Provided here is evidence showing that the stacking between triplet chromophores plays a critical role in ultralong organic phosphorescence (UOP) generation within a crystal. By varying the structure of a functional unit, and different on‐off UOP behavior was observed for each structure. Remarkably, 24CPhCz, having the strongest intermolecular interaction between carbazole units exhibited the most impressive UOP with a long lifetime of 1.06 s and a phosphorescence quantum yield of 2.5 %. 34CPhCz showed dual‐emission UOP and thermally activated delayed fluorescence (TADF) with a moderately decreased phosphorescence lifetime of 770 ms, while 35CPhCz only displayed TADF owing to the absence of strong electronic coupling between triplet chromophores. This study provides an explanation for UOP generation in crystal and new guidelines for obtaining UOP materials. 相似文献
11.
《中国科学:化学(英文版)》2020,(10)
Ultralong organic phosphorescence(UOP) materials have roused considerable attention in the field of photonics and optoelectronics owing to the feature of long-lived emission lifetimes. However, to develop UOP materials with color-tunability is still a formidable challenge. Here, we report a class of UOP materials containing carbonyl, amino or amide groups, exhibiting colortunable persistent luminescence ranging from blue(458 nm) to yellow-green(508 nm) under different UV wavelength excitation. Taken theoretical and experimental results together, we conclude that the excitation dependent color-tunable UOP emission is ascribed to multiple emission centers from single molecular and aggregated states in crystal. Given color-tunable UOP feature, these materials are used to successfully realize visual UV-light detection. This finding not only provides a strategy to design new organic phosphorescent molecules with colorful emission, but also extends the scope of the applications of purely organic phosphorescent materials. 相似文献
12.
Zhichao Cheng Dr. Huifang Shi Dr. Huili Ma Lifang Bian Qi Wu Long Gu Suzhi Cai Xuan Wang Prof. Wei‐wei Xiong Prof. Zhongfu An Prof. Wei Huang 《Angewandte Chemie (International ed. in English)》2018,57(3):678-682
A new type of materials, organic salts in the crystal state, have ultralong organic phosphorescence (UOP) under ambient conditions. The change of cations (NH4+, Na+, or K+) in these phosphors gives access to tunable UOP colors ranging from sky blue to yellow green, along with ultralong emission lifetimes of over 504 ms. Single‐crystal analysis reveals that unique ionic bonding can promote an ordered arrangement of organic salts in crystal state, which then can facilitate molecular aggregation for UOP generation. Additionally, reversible ultralong phosphorescence can be realized through the alternative employment of fuming gases (ammonia and hydrogen chloride), demonstrating its potential as a candidate for visual ammonic or hydrogen chloride gas sensing. The results provide an environmental responsible and practicable synthetic approach to expanding the scope of ultralong organic phosphorescent materials as well as their applications. 相似文献
13.
Jian-An Li Letian Zhang Dr. Chunlei Wu Zihao Huang Shufeng Li Huaqing Zhang Qingchen Yang Dr. Zhu Mao Prof. Suilian Luo Prof. Cong Liu Prof. Guang Shi Prof. Bingjia Xu 《Angewandte Chemie (International ed. in English)》2023,62(7):e202217284
In this work, an efficient polymer-based organic afterglow system, which shows reversible photochromism, switchable ultralong organic phosphorescence (UOP), and prominent water and chemical resistance simultaneously, has been developed for the first time. By doping phenoxazine (PXZ) and 10-ethyl-10H-phenoxazine (PXZEt) into epoxy polymers, the resulting PXZ@EP-0.25 % and PXZEt@EP-0.25 % films show unique photoactivated UOP properties, with phosphorescence quantum yields and lifetimes up to 10.8 % and 845 ms, respectively. It is found that the steady-state luminescence and UOP of PXZ@EP-0.25 % are switchable by light irradiation and thermal annealing. Moreover, the doped films can still produce conspicuous UOP after soaking in water, strong acid and base, and organic solvents for more than two weeks, exhibiting outstanding water and chemical resistance. Inspired by these exciting results, the PXZ@EP-0.25 % has been successfully exploited as an erasable transparent film for light printing. 相似文献
14.
Triarylboranes have recently emerged as a powerful new class of electron acceptors with great potential as optoelectronic materials. The empty p(z) orbital on the boron centre promotes strong charge-transfer transitions, leading to highly luminescent compounds with colors spanning the entire visible spectrum. Due to intense research efforts over the past decade, many examples now exist of organic molecules based on this structural motif. Only recently, however, have transition metal-containing triarylboranes been closely investigated. These compounds are capable of bright luminescence from a triplet excited state, and have been developed as efficient emissive materials for organic light-emitting diodes (OLEDs) as a result. In addition, their long-lived phosphorescence gives these materials potential as highly selective chemical sensors for small anions using time-gated detection, eliminating interference from background fluorescence. The research of the past several years has now led to a better understanding of the impact of the triarylboron group on the photophysical properties of metal complexes, which we expect will provide many opportunities for research into this class of functional phosphorescent materials. 相似文献
15.
Room-temperature phosphorescence (RTP) materials have attracted great attention due to their involvement of excited triplet states and comparatively long decay lifetimes. In this short review, recent progress on enhancement of RTP from purely organic materials is summarized. According to the mechanism of phosphorescence emission, two principles are discussed to construct efficient RTP materials: one is promoting intersystem crossing (ISC) efficiency by using aromatic carbonyl, heavyatom, or/and heterocycle/heteroatom containing compounds; the other is suppressing intramolecular motion and intermolecular collision which can quench excited triplet states, including embedding phosphors into polymers and packing them tightly in crystals. With aforementioned strategies, RTP from purely organic materials was achieved both in fluid and rigid media. 相似文献
16.
Supratim Banerjee 《Supramolecular chemistry》2020,32(4):287-311
ABSTRACT The field of room temperature phosphorescence (RTP) from purely organic materials has made rapid strides in recent years primarily due to its tremendous promise in the areas of photovoltaics, photocatalysis, bioimaging, sensing, etc. Although, the RTP properties, at one time, were considered to be exclusive features of organometallic and inorganic phosphors, a great progress in the molecular design coupled with a much better understanding of the triplet state stabilisation has led to the creation of a plethora of organic RTP materials in the current decade. In this focussed review, a special category of organic luminogens which, rather remarkably, exhibit efficient RTP emission in amorphous or fluidic state is discussed. A few selected examples of such ‘non-crystalline’ organic RTP luminogens are highlighted with an emphasis on the basic design principles and the strategies to increment the phosphorescence efficiency. 相似文献
17.
Zhu Wu Jrn Nitsch Julia Schuster Alexandra Friedrich Katharina Edkins Marcel Loebnitz Fabian Dinkelbach Vladimir Stepanenko Frank Würthner Christel M. Marian Lei Ji Todd B. Marder 《Angewandte Chemie (International ed. in English)》2020,59(39):17137-17144
Achieving highly efficient phosphorescence in purely organic luminophors at room temperature remains a major challenge due to slow intersystem crossing (ISC) rates in combination with effective non‐radiative processes in those systems. Most room temperature phosphorescent (RTP) organic materials have O‐ or N‐lone pairs leading to low lying (n, π*) and (π, π*) excited states which accelerate kisc through El‐Sayed's rule. Herein, we report the first persistent RTP with lifetimes up to 0.5 s from simple triarylboranes which have no lone pairs. RTP is only observed in the crystalline state and in highly doped PMMA films which are indicative of aggregation induced emission (AIE). Detailed crystal structure analysis suggested that intermolecular interactions are important for efficient RTP. Furthermore, photophysical studies of the isolated molecules in a frozen glass, in combination with DFT/MRCI calculations, show that (σ, B p)→(π, B p) transitions accelerate the ISC process. This work provides a new approach for the design of RTP materials without (n, π*) transitions. 相似文献
18.
Aakash D. Nidhankar Goudappagouda Divya S. Mohana Kumari Shailendra Kumar Chaubey Rashmi Nayak Rajesh G. Gonnade G. V. Pavan Kumar Retheesh Krishnan Sukumaran Santhosh Babu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):13179-13185
Room-temperature phosphorescence of metal and heavy atom-free organic molecules has emerged as an area of great potential in recent years. A rational design played a critical role in controlling the molecular ordering to impart efficient intersystem crossing and stabilize the triplet state to achieve room-temperature ultralong phosphorescence. However, in most cases, the strategies to strengthen phosphorescence efficiency have resulted in a reduced lifetime, and the available nearly degenerate singlet-triplet energy levels impart a natural competition between delayed fluorescence and phosphorescence, with the former one having the advantage. Herein, an organic helical assembly supports the exhibition of an ultralong phosphorescence lifetime. In contrary to other molecules, 3,6-phenylmethanone functionalized 9-hexylcarbazole exhibits a remarkable improvement in phosphorescence lifetime (>4.1 s) and quantum yield (11 %) owing to an efficient molecular packing in the crystal state. A right-handed helical molecular array act as a trap and exhibits triplet exciton migration to support the exceptionally longer phosphorescence lifetime. 相似文献
19.
Pure organic room temperature phosphorescence (RTP) has been attracting a lot interest recently. So far, many strategies have succeeded in achieving efficient organic RTP materials by increasing the rate of intersystem crossing (ISC) and suppressing non-radiative transitions. In supramolecular chemistry, the control and regulation of molecular recognition based on the role of the host and guest in supramolecular polymers matrix, has attracted much attention. Recently, researchers have successfully achieved room temperature phosphorescence of pure organic complexes through host-guest interactions. The host molecule specifically includes the phosphorescent guest to reduce non-radiative transitions and enhance room temperature phosphorescence emission. This review aims to describe the developments and achievements of pure organic room temperature phosphorescence systems through the mechanism of host-guest interactions in recent years, and demonstrates the exploration and pursuit of phosphorescent materials of researchers in different fields. 相似文献
20.
Aakash D. Nidhankar Goudappagouda Divya S. Mohana Kumari Shailendra Kumar Chaubey Rashmi Nayak Rajesh G. Gonnade G. V. Pavan Kumar Retheesh Krishnan Sukumaran Santhosh Babu 《Angewandte Chemie (International ed. in English)》2020,59(31):13079-13085
Room‐temperature phosphorescence of metal and heavy atom‐free organic molecules has emerged as an area of great potential in recent years. A rational design played a critical role in controlling the molecular ordering to impart efficient intersystem crossing and stabilize the triplet state to achieve room‐temperature ultralong phosphorescence. However, in most cases, the strategies to strengthen phosphorescence efficiency have resulted in a reduced lifetime, and the available nearly degenerate singlet‐triplet energy levels impart a natural competition between delayed fluorescence and phosphorescence, with the former one having the advantage. Herein, an organic helical assembly supports the exhibition of an ultralong phosphorescence lifetime. In contrary to other molecules, 3,6‐phenylmethanone functionalized 9‐hexylcarbazole exhibits a remarkable improvement in phosphorescence lifetime (>4.1 s) and quantum yield (11 %) owing to an efficient molecular packing in the crystal state. A right‐handed helical molecular array act as a trap and exhibits triplet exciton migration to support the exceptionally longer phosphorescence lifetime. 相似文献