Advanced Optical Materials
·
2021
·Vol. 9
·期 19
·2100689
·
IF 9.926
Ruiling Zhang,Zhongyi Wang,Xin Xu,Xin Mao,Jin Xiong,Yang Yang,Keli Han
Halide double perovskites have been regarded as promising alternatives to famous lead halide perovskites in the field of luminescent materials. However, the low-emission efficiency of pristine ones and the lack of efficient blue emitters remain considerable obstacles for their applications in light-emitting devices. Here, an air-stable, all-inorganic Sc-based double perovskite Cs 2 NaScCl 6 is reported, which exhibits strong blue emission peaking at 445 nm with an averaged quantum yield of 29.05% (the highest reported value for pristine halide double perovskites). The rare-earth double perovskite also shows excellent stability against heat and irradiation. Bulk perovskite Cs 2 NaScCl 6 can be an effective host to incorporate Mn 2+ ions, yielding interesting tunable dual broadband emission, slightly redshifted blue emission (450 nm) from the host and red emission (635 nm) from Mn 2+ d–d transitions. These findings present a new direction toward the design of high-efficiency, stable, and environmentally friendly perovskite light emitters.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
DYES AND PIGMENTS
·
2017
·
IF 3.473
Yafei Wang,Wanhui Liu,Zuoming Qu,Hua Tan,Yu Liu,Guohua Xie,Weiguo Zhu
To explore the structure-property of donor-acceptor (D-A) type blue emitter, in this contribution, four star-shaped compounds of p -TPA, m -TPA, p -TPA-TPE and m -TPA-TPE using spirotriphenylamine as the donor unit and triazine as the acceptor core were designed and prepared. The tetraphenylethene (TPE) unit was introduced into the D-A molecules to enhance the emission efficiency in solid state. The photophysical properties of all compounds were comparatively studied through experimental and theoretical methods. All these D-A compounds displayed blue emission (443–487 nm) both in solution and neat film. Compared to p -TPA and m -TPA, p -TPA-TPE and m -TPA-TPE possessed clear aggregated-induced emission (AIE) property and higher emission efficiency in the solid state. Both the doped and non-doped organic light-emitting diodes (OLEDs) based on m -TPA and m -TPA-TPE were fabricated by solution-processable approach. The m -TPA-TPE based non-doped device showed a satisfying performance with a high current efficiency of 4.2 cd/A and an external quantum efficiency of 1.8% in the bluish-green region. This research demonstrates that integrating AIE unit into D-A molecule is an effective strategy for design high efficient blue emitter in non-doped OLEDs.
研究领域:
材料科学
·
光学
·
化学
✓ 已验证
DOI
高影响因子
Small
·
2023
·
IF 13.3
Zhiyuan He,Chencheng Peng,Runda Guo,Ben Chen,Xin Li,Xiangyu Zhu,Jian Zhang,Wenxi Liang,Lei Wang
The fabrication of perovskite light-emitting diodes (PeLEDs) with vacuum deposition shows great potential and commercial value in realizing large-area display panel manufacturing. However, the electroluminescence (EL) performance of vacuum-deposited PeLEDs still lags behind the counterparts fabricated by solution process, especially in the field of blue PeLEDs. Here, the fabrication of high-quality CsPbBr 3− x Cl x film through tri-source co-evaporation is reported to achieve high photoluminescence quantum yield (PLQY). Compared with the conventional traditional dual-source co-evaporation, the tri-source co-evaporation method allows for freely adjustable elemental ratios, enabling the introduction of the lattice-matched Cs 4 Pb(Br/Cl) 6 phase with the quantum-limited effect into the inorganic CsPb(Br/Cl) 3 emitter. By adjusting the phase distribution, the surface defects of the emitter can be effectively reduced, leading to better blue emission and film quality. Further, the effects of Cs/Pb ratio and Br/Cl ratio on the PLQY and carrier recombination dynamics of perovskite films are investigated. By optimizing the deposition rate of each precursor source, spectrally stable blue PeLEDs are achieved with tunable emission ranging from 468 to 488 nm. Particularly, the PeLEDs with an EL peak at 488 nm show an external quantum efficiency (EQE) of 4.56%, which is the highest EQE value for mixed-halide PeLEDs fabricated by vacuum deposition.
研究领域:
材料科学
·
光电技术
·
半导体物理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·Vol. 34
·期 36
·2401297
·
IF 18.5
Lu Wang,Zhen-Huang Su,Yang Shen,Shi-Chi Feng,Feng-Ming Xie,Kai Zhang,Ke-Fan Meng,Xingyu Gao,Jian-Xin Tang,Yan-Qing Li
Metal halide perovskite light-emitting diodes (PeLEDs) are gaining increasing attention as a promising candidate for the new-generation display technology. Although tremendous progress has been witnessed in this field, the device performance of blue PeLEDs still lags far behind that of the green and red counterparts. In this work, an effective interfacial engineering is employed to boost the radiative recombination of blue perovskite film by introducing a multifunctional tetraethyl orthosilicate (TEOS) network on the grain-growth substrate. Benefitting from the strong interaction between the TEOS molecule and perovskite nuclei, the perovskite crystallization dynamics are effectively regulated, contributing to significantly improved emitting film with uniformly distributed halogen and concentrated low-dimensional domain. Additionally, the TEOS network can distinctly passivate the crystal defects at the buried perovskite interface owing to its adequate electron-donating sites. Consequently, the target blue PeLEDs featuring a stable emission peak at 488 nm exhibit a champion external quantum efficiency of 17.3%, which is among the highest values to date. The results demonstrate the critical role of the surface molecular characteristics of the grain-growth substrate in regulating the mixed-halide blue perovskite crystallization.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
高影响因子
NANO LETTERS
·
2018
·
IF 12.08
Meiying Leng,Ying Yang,Zhengwu Chen,Wanru Gao,Jian Zhang,Guangda Niu,Dengbing Li,Haisheng Song,Jianbing Zhang,Song Jin,Jiang Tang
Metal halide perovskite quantum dots (QDs) recently have attracted great research attentions. However, blue-emitting perovskite QDs generally suffer from low photoluminescence quantum yield (PLQY) because of easily formed defects and insufficient surface passivation. Replacement of lead with low toxicity elements is also preferred toward potential commercial applications. Here, we apply Cl-passivation to boost the PLQY of MA3Bi2Br9 QDs to 54.1% at the wavelength of 422 nm, a new PLQY record for blue emissive, lead-free perovskite QDs. Because of the incompatible crystal structures between MA3Bi2Br9 and MA3Bi2Cl9 and the careful kinetic control during the synthesis, Cl– anions are engineered to mainly locate on the surface of QDs acting as passivating ligands, which effectively suppress surface defects and enhance the PLQY. Our results highlight the potential of MA3Bi2Br9 QDs for applications of phosphors, scintillators, and light-emitting diodes.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2023
·Vol. 11
·期 17
·2202726
·
IF 9
Qianwen Guan,Huang Ye,Tingting Zhu,Xinyuan Zhang,Shihai You,Jianbo Wu,Youxuan Zheng,Xitao Liu,Junhua Luo
Chiral halide perovskites have emerged as promising circularly polarized light sources due to their great potential applications in 3D displays, optical data storage, and optical communication devices. However, to date, chiral halide perovskites with efficient blue circularly polarized luminescence (CPL) are scarcely unearthed. Herein, through formamidine engineering to decrease lattice distortion, the first new types of chiral corrugated 2D halide perovskites are presented ( R / S )-(BPEA)FAPbBr 4 ·H 2 O (2- R / S ) (BPEA = 4-bromophenylethylaminium, FA = formamidinium). Interestingly, driven by the incorporation of FA organic cations, the chiral perovskite layer realizes the transformation from (100)-oriented ( R / S )-(BPEA) 2 PbBr 4 ·H 2 O (1- R / S ) to (110)-oriented 2- R / S accompanying with reduced lattice distortion. More importantly, (110)-oriented chiral perovskites 2- R exhibit remarkable blue CPL with large asymmetry factors ( g lum =8.4 × 10 −3 ). This work offers an exciting approach to realizing efficient blue CPL and promotes their further applications in photoelectronic devices.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COORDINATION CHEMISTRY
·
2017
·
IF 1.795
Bu-Lin Chen,Li Liu,Xin-Xin Zhong,Abdullah M. Asiri,Khalid A. Alamry,Fa-Bao Li,Nian-Yong Zhu,Wai-Yeung Wong,Hai-Mei Qin
Three-coordinate copper halide complexes with a bidentate phosphine ligand have received much attention. Here, a series of three-coordinate dinuclear copper halide complexes containing a diphenylamino monodentate phosphine ligand, [CuX(dpnp)]2 (dpnp = N-[2-(diphenylphosphino)-4,5-dimethylphenyl]-N-phenylaniline, X = I (1), Br (2) and Cl (3)), were synthesized, and their molecular structures and photophysical properties were investigated. The structural analysis reveals that two copper(I) centers are bridged by two halogen ligands to form a dinuclear structure with a four-membered Cu2X2 ring. Crystal structures of 1–3 contain 1-D supramolecular arrays constructed by intermolecular C–H⋯π interactions. These complexes exhibit blue emission in the solid state at room temperature and have peak emission wavelengths at 483–487 nm with microsecond lifetimes (τ = 13.9–38.1 μs) and low emission quantum yields (<0.01%). The emission of complex 1 mainly originates from intraligand (IL) transition, whereas the emissions of complexes 2 and 3 are from a combination of MLCT, XLCT and IL transitions. The three complexes displayed good thermal stability.
研究领域:
无机化学
·
材料科学
·
光物理学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2021
·Vol. 31
·期 45
·2103870
·
IF 18.808
Yang Shen,Hai-Yan Wu,Yan-Qing Li,Kong-Chao Shen,Xingyu Gao,Fei Song,Jian-Xin Tang
Efficient and stable blue emission of perovskite light-emitting diodes (PeLEDs) is a requisite toward their potential applications in full-color displays and solid-state lighting. Rational manipulation over the entire electroluminescence process is promising to break the efficiency limit of blue PeLEDs. Herein, a facile device architecture is proposed to achieve efficient blue PeLEDs for simultaneously reducing the energetic loss during electron-photon conversion and boosting the light outcoupling. Effective interfacial engineering is employed to manipulate the perovskite crystallization nucleation, enabling highly compact perovskite nanocrystal assemblies and suppressing the trap-induced carrier losses by means of interfacial hydrogen bonding interactions. This strategy contributes to a high external quantum efficiency (EQE) of 12.8% for blue PeLEDs emitting at 486 nm as well as improved operational stability. Moreover, blue PeLEDs reach a peak EQE of 16.8% with the incorporation of internal outcoupling structures for waveguided light, which can be further raised to 27.5% by integrating a lens-based structure for substrate-mode light. These results verify the validity of this strategy in producing efficient and stable blue PeLEDs for practical applications.
研究领域:
材料科学
·
光电技术
·
显示技术
✓ 已验证
DOI
高影响因子
ACS Applied Optical Materials
·
2023
·
IF 0
Huazheng Li,Gaoling Zhao,Bin Song,Weixia Dong,Gaorong Han
In recent years, deep-blue perovskite light-emitting diodes (PeLEDs) based on ultra-small CsPbBr3 quantum dots (QDs) have attracted increased attention. However, ultra-small CsPbBr3 QDs tend to have more defects and more nonradiative processes because of their ultrafast nucleation and growth rates. How to suppress the nucleation and growth rate is an important issue for developing deep-blue emitting CsPbBr3 QDs with high performance. Herein, a modified hot-injection method (MM) is designed for suppressing the growth process of CsPbBr3. The ligands of oleic acid (OA) and oleylamine (OAm) are employed instead of octadecene (ODE) as the solution, and as a result, the strong confined and high-quality CsPbBr3 QDs (∼4.45 nm) are obtained, presenting strong deep-blue emission (≈465 nm) with a photoluminescence quantum yield (PLQY) of 95%, an average lifetime of 8.84 ns, and a large exciton binding energy of 268.7 meV, which can maintain blue emission over 30 days under atmospheric conditions. Compared with the CsPbBr3 nanocubes (NCs) obtained by the common hot-injection method (CM), the CsPbBr3 QDs obtained by MM have fewer defects and trap states, resulting in less nonradiative processes. In addition, the fabricated PeLEDs based on the above CsPbBr3 QDs show deep-blue emission with Commission Internationale de l’Eclairage (CIE) color coordinates of (0.129 and 0.074), which is better than the blue standard of the National Television Standards Committee (NTSC). Evidently, this work provides a way to synthesize ultra-small CsPbBr3 QDs and also reflects the important influence of the reaction solvent on perovskite synthesis.
研究领域:
材料科学
·
纳米技术
·
光电工程
✓ 已验证
DOI
ORGANIC ELECTRONICS
·
2021
·
IF 3.721
Yanyan Wu,Fang Yuan,Feifei Fu,Chenxing Liu,Bo Jiao,Fanghui Zhang,Zhaoxin Wu
Since the emergence of organic-inorganic hybrid perovskites , the development of perovskite light-emitting diodes (PeLEDs) with green/red emission have made great progress, and the corresponding external quantum efficiency (EQE) has exceeded 20%. However, the research progress of blue-emitting PeLED still has certain challenges. In this article, a multi-cation per-bromine perovskite film is prepared by introducing polymer molecules poly(9-vinylcarbazole) (PVK) in an anti-solvent (chloroform). When the concentration of PVK is optimized to 0.1 mg/mL, a smooth, dense, high-quality film with photoluminescence quantum efficiency (PLQY) up to 20.70% is obtained. The introduction of PVK can assist the formation of perovskite films for interface modification via surface defect passivation . The optimized blue PeLED has a maximum brightness of 3136 cd/m 2 and a maximum EQE of 3.49% at 488 nm. More importantly, the optimized blue PeLED has excellent color stability under high applied voltage up to 12 V or continuous operation.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2021
·
IF 4.098
Ying Fang,Yuanyuan Meng,Chunming Yuan,Chunhui Du,Kun-Peng Wang,Shaojin Chen,Zhi-Qiang Hu
Organic fluorescent molecules with π-conjugated system have shown great importance in numerous applications including bioimaging and optoelectronics. Planar aggregation-induced emissive (AIE) organic compounds with efficient solid-state luminescence are rarely developed and urgently needed in various applications. In this work, highly planar 4-styrylbenzonitrile derivatives have been synthesized. Most of these compounds show strong AIE properties with hundred-fold fluorescent enhancement. Moreover, these molecules are deep blue emissive in solid state, exhibiting good to excellent fluorescence quantum efficiency. The single crystal analysis shows that adjacent molecules could form special J-type aggregation. The intramolecular rotations are efficiently restricted by various noncovalent interactions. These molecular arrangements could be essential for the observed strong emission in aggregated and solid state. This work has paved a new path to efficient AIE-active organic emitters with highly planar conformations from 4-styrylbenzonitrile structure.
研究领域:
有机化学
·
材料科学
·
光电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY A
·
2017
·
IF 2.847
Tao Wang,Ziye Wu,Wei Sun,Shengye Jin,Xingyuan Zhang,Chuanyao Zhou,Jun Jiang,Yi Luo,Guoqing Zhang
We report the formation of macroscopic wires up to centimeters in length from a series of structurally flexible, covalently tethered small-molecular fluorophore-quencher dyads (FQDs, average MW = 425 Da), comprised of carbazole, melatonin, and cyanobenzoate moieties. These FQDs are nonemissive in organic solutions but become moderately to highly luminescent (ΦF = 0.037–0.39) upon formation of wires with emission maxima in the blue region (446–483 nm). The blue photoluminescence (PL) is ascribed to a combination of singlet charge transfer, localized triplet state, and possibly delayed fluorescence emissions with intrinsic luminescence lifetimes ranging from 0.228 to 21333 μs, based on luminescence, transient absorption measurements, X-ray diffraction, and calculations.
研究领域:
材料科学
·
物理化学
·
光电子学
·
纳米技术
·
有机电子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）