CHEMISTRY OF MATERIALS
·
2023
·
IF 8.6
Meng Gao,Yuexiao Pan,Chengdong Peng,Yihong Ding,Hongzhou Lian,Liyi Li,Jun Lin
Single-component white light emitters are particularly attractive for fabricating economical solid-state devices for display and lighting. Herein, an efficient white light with photoluminescence quantum yields approaching 98% has been obtained in Mn2+ and Pb2+ co-doped Cs7Cd3Br13 crystals. The quantified bonding and nonbonding characters calculated by the crystal orbital Hamilton population analysis demonstrate that the Mn2+ and Pb2+ occupy preferentially in the [CdBr4]2– tetrahedrons rather than the [CdBr6]4– octahedrons in Cs7Cd3Br13. According to the PL spectral characteristic and the theoretical results, the broadband white light emission from Cs7Cd3Br13:Pb2+,Mn2+ crystals is ascribed to the multiple PL origins, i.e., the first self-trapped exciton (STE1) from the intrinsic trapping states of host lattice Cs7Cd3Br13, the d–d transition of Mn2+, and the second self-trapped exciton (STE2) induced by the introduction of Pb2+, respectively. The results calculated by density functional theory reveal that the incorporation of Mn2+ and Pb2+ has significantly improved the thermodynamic stability of the Cs7Cd3Br13 structure with lower defect formation energies, which is verified by the experimental observation in the temperature-dependent PL spectra of the emitting crystals. The findings here provide a new perspective for a single-component white light via creating multiple PL centers in a single matrix as well as help in the elucidation of the preferential site occupancy mechanism of the dopants in different symmetrical units.
研究领域:
材料科学
·
光学
·
固体物理
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry Letters
·
2023
·
IF 5.7
Yacong Li,Chuying Wang,Guangyong Xu,Guigen Luo,Zhengtao Deng
The absorption and photoluminescence (PL) of CsMnBr3 with Mn(II) in octahedral crystal fields are extremely weak due to a d–d forbidden transition. Herein, we introduce a facile and general synthetic procedure that can prepare undoped and heterometallic doped CsMnBr3 NCs at room temperature. Importantly, both PL and absorption of CsMnBr3 NCs were significantly improved after doping a small amount of Pb2+ (4.9%). The absolute photoluminescence quantum yield (PL QY) of Pb-doped CsMnBr3 NCs is up to 41.5%, 11-fold higher than undoped CsMnBr3 NCs (3.7%). The PL enhancement is attributed to the synergistic effects between [MnBr6]4– units and [PbBr6]4– units. Furthermore, we verified the similar synergistic effects between [MnBr6]4– units and [SbBr6]4– units in Sb-doped CsMnBr3 NCs. Our results highlight the potential of tailoring luminescence properties of manganese halides through heterometallic doping.
研究领域:
材料科学
·
纳米技术
·
光电子学
·
无机化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Qiuyu Cheng,Xin Chen,Lin Liu,Peng Jiang,Deshi Song,M.A. Subramanian
Novel green and blue chromophores based on Ni/Co/Cr doped BaMg 6 Ti 6 O 19 solid solutions are successfully synthesized through a solid-state reaction. The crystal structure of all the samples belongs to the magnetoplumbite structure with the space group of P 6 3 / mmc . The BaMg 6- x /2 Ti 6- x /2 Ni x O 19 (0 ≤ x ≤ 0.3) compounds exhibit a light green ( x = 0.1) to yellow-green ( x = 0.3) color. The oxidation state of Ni is confirmed to be +2 valence and the d-d transition of Ni 2+ in octahedral sites is responsible for color. BaMg 6- x /2 Ti 6- x /2 Co x O 19 (0 ≤ x ≤ 0.3) series show a blue color and the intensity of blueness is increasing with the increase of Co content. The blue color is due to d-d transitions within Co 2+ present in the tetrahedral sites. For BaMg 6- x /2 Ti 6- x /2 Cr x O 19 (0 ≤ x ≤ 2) phases the color varies from light green ( x = 0.2) to green ( x = 2). Chromium exists in +3 and + 6 oxidation states and the observed color is due to charge transfer transition between Cr 3+ –Ti 4+ and d-d transitions within octahedral Cr 3+ sites resulting in strong absorption in the visible region. The synthesized colored oxides are mixed with PMMA to prepare novel green and blue PMMA polymer composites to evaluate their compatibility in plastics.
研究领域:
材料科学
·
固体化学
·
光学材料
·
聚合物科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Shuai Zhang,Yifei Zhao,Jiadong Zhou,Hong Ming,Chun-Hai Wang,Xiping Jing,Shi Ye,Qinyuan Zhang
Manganese (II) compounds are promising luminescent candidates for white light-emitting diodes (WLEDs) applications. However, the forbidden d - d transition of Mn 2+ ion makes the absorption of blue light and emission relatively weak without a sensitizer. The strategy of isolating MnX n (X is the ligand) with some ionic liquids is used to design two new hybrid compounds in this study, focusing on the orbital hybridization to relax the parity selection rule of the d - d transition. A large hindrance of the organic cations in the two new Manganese (II) hybrids enables a large Mn-Mn distance (up to ~ 10 Å) to form zero-dimensional (0D) structures, and the Mn sites in both compounds have a low site symmetry ( C 2 or C 1 ). The 0D structure of MnX n polyhedral is beneficial to isolatedly investigate the orbital hybridization of the ligand and Mn 2+ ion. A higher orbital hybridization extent for Mn-Br bond is evidenced by Density Functional Theory (DFT) simulation. This conclusion leads to the strong and stable green light emissions under preferable blue light (460 nm) excitations, giving photoluminescence quantum yields (PLQYs) as high as 76%. The WLEDs fabricated with these compounds have presented high luminous efficiency up to ~130 lm/W and survived multiple stability tests. The research favors the discovery of ideal Mn compounds for displays and lighting applications.
研究领域:
材料科学
·
光电
·
光子学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Shi-Wen Lv,Xiaoran Wang,Xing Wei,Yi Zhang,Yanqing Cong,Lin Che
Nowadays photocatalysis assisted advanced oxidation processes exhibited a great application prospects in pollution control. Herein, for the first time, a series of transition metal modified UiO-66-NH 2 (namely Fe-UiO-66-NH 2 , Co-UiO-66-NH 2 and Ni-UiO-66-NH 2 ) were synthesized via a simple method. After that, these functional materials were employed as photocatalyst to activate PMS for degrading BPA under visible light irradiation. Significantly, prepared Fe-UiO-66-NH 2 exhibited the highest photocatalytic activity among these samples. More importantly, proposed Fe-UiO-66-NH 2 /PMS/light oxidation system showed excellent degradation ability for various organic pollutants, including BPA, TC, OFX, IBP as well as SMX. Owing to the occurrence of d-d transitions after the coordination of transition metal ions, UiO-66-NH 2 displayed the enhanced utilization efficiency of visible light. Furthermore, introduced Fe ion as a mediator could boost the charge transfer by the cluster-to-metal way, thereby effectively inhibiting the recombination of photogenerated electrons and holes. In addition, embedding cluster-to-metal charge transfer in UiO-66-NH 2 modified the band structure, and both SO 4 −• and OH were major active species in the photocatalytic reaction system. Developed Fe-UiO-66-NH 2 /PMS/light oxidation system with good stability also presented great antibacterial performance. To sum up, current work could provide some novel inspirations for designing the high-efficiency photocatalyst.
研究领域:
环境科学
·
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Laser & Photonics Reviews
·
2024
·
IF 9.8
Zhengwei Yang,Haolin Lu,Yu Zhang,Baipeng Yin,Hong Wang,Sehrish Gull,Wei Qin,Yongsheng Chen,Jiannian Yao,Chuang Zhang,Guankui Long
Chiral perovskites are considered as promising candidates for circularly polarized luminescence (CPL) light source, by attracting the broader scientific community for their applications in chiral optoelectronics and spintronics. However, it is still a great challenge to achieve both substantial photoluminescence asymmetry ( g CPL ) and high photoluminescence quantum yield (PLQY) simultaneously for high CPL brightness due to the limitations associated with magnetic transition dipole moments. Herein, this problem is overcome and achieve both large g CPL of 1.6×10 −2 and PLQY of 56% in chiral perovskite through the magnetic element doping strategy. The substitution of Pb 2+ ion with smaller magnetic Mn 2+ ions shrinks the crystal lattice around [MnBr 6 ] 4− octahedra, amplifying the asymmetric distortion surrounding the Mn 2+ ions. Moreover, the transition associated with Mn 2+ ions can harvest the photoexcitation energy in chiral perovskites, and its spin-flipping characteristics enable highly efficient CPL from the d–d transition on Mn 2+ energy levels. Furthermore, this magnetic element doping strategy is proven to be a universal tactic for enhancing CPL brightness as confirmed in a series of 1D- or 2D-chiral perovskites with various chiral ligands or halogens. The findings provide an in-depth understanding of the structure-property relationship in chiral perovskites toward chiral optoelectronic and spintronic applications.
研究领域:
材料科学
·
光电子学
·
自旋电子学
✓ 已验证
产品关联
DOI
高影响因子
SOLID STATE SCIENCES
·
2022
·
IF 3.752
Yi Wang,Peng Jiang,M.A. Subramanian,Wenbin Cao
Single phase Al 2-2 x Ni x Ti 1+ x O 5 (0 ≤ x ≤ 0.4) solid solutions were successfully synthesized by solid-phase reaction. The color of the compounds varied from yellow ( x = 0.1) to turmeric ( x = 0.4) with increasing nickel content. X-ray photoelectron spectroscopy analysis confirmed that the oxidation state of Ni is +2. The UV–Vis absorption spectrum showed that the color of the sample comes from the d-d transition of Ni 2+ in octahedral coordination. Owing to excellent high temperature stability, the as-prepared oxide powders (10 wt%) were mechanically mixing with Al 2 O 3 by conventional ball milling to prepare colored alumina ceramics. When Al 2 O 3 is in excess, the blue NiAl 2 O 4 impurity phase appeared, contributing to an intense green color of the Al 2 O 3 ceramics composite. The Vickers micro hardness value of green alumina was higher than that of pure white alumina. The as-prepared samples were also dispersed in PMMA and bright yellow polymer composites were obtained, indicating great potential in polymer colorant.
研究领域:
材料科学
·
陶瓷
·
颜料化学
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
Light-Science & Applications
·
2025
·Vol. 14
·期 1
·1-10
·
IF 23.4
Gu Simin,Lian Huiwang,Kuang Rongyi,Lou Bibo,Ma Chonggeng,Liu Gaochao,Wang Jing
Laser-driven near-infrared II (NIR-II) light sources comprising luminescent ceramics represent a promising research frontier, yet their development remains constrained by the external quantum efficiency (EQE) and thermal stability bottleneck of current luminescent materials. Herein, we present a non-equivalent cation substitution strategy to fabricate high-efficiency translucent MgO:Ni 2+ , Cr 3+ NIR-II luminescent ceramics. The co-doping of Cr 3+ induces structural distortion at Ni 2+ -occupied octahedral sites, effectively breaking the parity-forbidden d-d transition constraint while enabling efficient energy transfer from Cr 3+ to Ni 2+ . These synergistic effects yield remarkable internal and external quantum efficiencies of 61.06% and 39.69%, respectively. The developed ceramic demonstrates exceptional thermal management capabilities with 31.28 W·m −1 ·K −1 thermal conductivity and 92.11% emission retention at 478 K. When integrated into laser-driven NIR-II light sources, the system achieves record-breaking performance of 214 mW output power under 21.43 W/mm 2 blue laser excitation. Practical demonstrations showcase superior non-destructive imaging capabilities with 5.29 lp/mm spatial resolution and 0.97 contrast ratio. This work establishes a new paradigm for developing high-performance NIR-II light sources in advanced imaging and detection technologies.
研究领域:
光学材料
·
光子学
·
固态照明
·
生物医学成像
·
激光技术
·
陶瓷工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2020
·Vol. 31
·期 11
·8464-8471
·
IF 2.22
Si Shufang,Deng Hongmei,Wang Tiantian,Yang Pingxiong,Chu Junhao
Perovskite compounds Bi 0.7 A 0.3 FeO 3−δ (BAFO) (A = Ca, Sr, Pb, and Ba) with improved optical and magnetic properties have been synthesized by solid-state method. The effect of bivalent ions substitution on the phase transition, microstructure, optical, and magnetic properties are investigated in detail. X-ray diffraction and Raman scattering spectra analyses indicate the phase transition from rhombohedral to cubic in doped samples and the coexistence of the two phases in BBFO, inducing strong lattice distortions. A blue shift observed in d–d transitions energies can reveal the decreased internal chemical pressure, thus leading to the slight increase in bandgaps of BSFO, BPFO, and BBFO. While, narrowed bandgap of 1.96 eV can be found in BCFO for the increased tailing of the conduction band edge into the gap. Besides, room-temperature ferromagnetism has been observed in Sr-, Pb-, and Ba-doped samples which can be resulted from the suppression of spiral structure of BFO. These results lay a solid foundation on further exploring the potential abilities of BFO ceramics as multiferroic photovoltaic materials.
研究领域:
材料科学
·
固体物理
·
光电
·
磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Chen Li,Jun'an Lai,Daofu Wu,Qiang Wang,Yanjun Bai,Peng He,Kang An,Xiaosheng Tang
Metal halide with high luminescence property have emerged as the novel candidate materials for X-ray detection and imaging. However, the toxicity of some metal cations , such as Pb 2+ , limits its further widespread application. In this work, a new of lead-free pyridine manganese halide (C 5 H 6 N) 2 MnBr 4 was synthesized by the solution-processed method in room temperature . The research results show (C 5 H 6 N) 2 MnBr 4 has a typical structure of tetrahedral coordination related to d-d transition, which has a strong green emission at 520 nm with a full width at half maximum (FWHM) of 45 nm. (C 5 H 6 N) 2 MnBr 4 exhibits high photoluminescence quantum yields (PLQYs) of 59.36%, appreciable light yield of 15400 photons/MeV which is much higher than lead halide, relative short PL decay lifetime (247 μs) which is shorter than previous reported manganese halide and ultrashort RL decay time (12.24 ns). Finally, the performance of (C 5 H 6 N) 2 MnBr 4 Scintillators was verified via X-ray imaging, and clear X-ray image was obtained. (C 5 H 6 N) 2 MnBr 4 scintillators are eco-friendly and easy-synthesize while it has many superior performances: large stokes shift to reduce self-absorption of light; high PLQY to enhance scintillation performances; short decay lifetime to improve response. Thus, (C 5 H 6 N) 2 MnBr 4 shows great potential as next generation of scintillators and this work provides a new way for the preparation of simple and low-cost metal halide scintillators.
研究领域:
材料科学
·
放射学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
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