NANOTECHNOLOGY
·
2020
·Vol. 31
·期 21
·215605
·
IF 3.551
Yu-Wei Liu,Shao-Hong Guo,Si-Qi You,Chun-Yi Sun,Xin-Long Wang,Liang Zhao,Zhong-Min Su
Halide perovskites have been employed as photocatalysts for CO2 photoreduction due to their excellent optical properties and unique electronic structure. However, their photocatalytic performance is relatively poor. Herein, we demonstrate a new strategy with Mn-doped CsPb(Br/Cl)3 mixed-halide perovskites as catalysts to enhance the efficiency of CO2 photoreduction. By tuning the content of Mn, a series of CsPb(Br/Cl)3:Mn perovskites are obtained and show high efficiency in CO2 conversion to CO and CH4. For the optimum catalyst sample, especially, the yields of CO and CH4 reach 1917 μmol g−1 and 82 μmol g−1 which are 14.2 and 1.4 times higher than those of CsPbBr3. This work provides new insights into improving the reactivity of perovskites in CO2 photoreduction.
研究领域:
材料科学
·
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 12
·2026
·
IF 5.719
Weizhuo Zhang,Xin Li,Chencheng Peng,Fei Yang,Linyuan Lian,Runda Guo,Jianbing Zhang,Lei Wang
Colloidal cesium lead halide (CsPbX3, X = Cl, Br, and I) perovskite nanocrystals (NCs) demonstrate supreme optical properties in the spectra region of infrared, red, and green. High-performance blue-emitting counterparts are still eagerly required for next-generation full-color displays. However, it is challenging to obtain efficient blue perovskite NCs, especially in a deep blue region with an emission wavelength of around 460 nm or shorter. Herein, calcium halide and ammonium ions are applied simultaneously to modify the CsPb(Br/Cl)3NCs in situ to reduce surface defects, finally remarkably enhancing the photoluminescence quantum yield (PLQY) from 13% to 93% with an emission peak at 455 nm and the Commission Internationale de l’Eclairage (CIE) coordinates at (0.147, 0.030), which is close to the requirement of the Rec.2020 standard and also meets the requirement of blue emission in DCI-P3. Bright white emission and a wide color gamut are also achieved by combining the commercial red-emitting and green-emitting phosphors. The combination of time-resolved PL spectra and femtosecond transient absorption results discloses the reason for PLQY improvement as suppressing the nonradiative recombination.Keywords:CsPb(Br/Cl)3nanocrystals;surface passivation;blue emission;ammonium ion;calcium
研究领域:
材料科学
·
光电技术
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Le Ma,Xiansheng Li,Xuehan Chen,Jingyu Li,Pengfei Liu,Changting Wei,Qingshan Ma,Leimeng Xu,Wenhua Zhang,Jizhong Song
Mixed halide CsPb(Br/Cl) 3 quantum dots (QDs) exhibit fine tunable blue light and narrow photoluminescence (PL) full-width at half-maximum (FWHM), which has attracted significant attention as a promising candidate to realize a new generation of blue light technology. However, the introduction of Cl − makes it very easy to be eroded by water in the environment, which will lead to deep-level defects and degrade the luminescence and stability of QDs. Here, we propose to introduce tetra- n -octylammonium oxalate (TOAOxa) to improve the water-resistance stability and exciton recombination of CsPb(Br/Cl) 3 QDs and QD-based light-emitting diodes (QLEDs). The oxalate ion (Oxa 2− ) of TOAOxa could form strong interaction with undercoordinated Pb 2+ on CsPb(Br/Cl) 3 QD surface, which was confirmed by FTIR and XPS analysis. Oxa 2− passivated QDs (Oxa-QDs) exhibited improved photoluminescence quantum yield (PLQY) and enhanced water-resistance stability compared to pristine QDs. For example, after soaking in water–acetone co-solvent for 1 h, Oxa-QDs can maintain the initial cubic morphology and 43.9% of initial PL intensity, while the morphology and luminescence of pristine QDs are almost damaged. Based on the above concept, the Oxa-QD-based QLED presented a maximum external quantum efficiency (EQE) of 4.0%, and operational lifetime (T 50 ) of 84 s, which was a 5-fold enhancement in EQE, and 7-fold enhancement in stability compared to pristine QLED, respectively. Besides, the Oxa-QD-based QLED exhibits better stability in high-humidity air. To sum up, the Oxa 2− passivation strategy has significantly improved the efficiency and water-resistant stability of QDs and devices and would rapidly promote the development of blue-emitting QDs.
研究领域:
材料科学
·
光电技术
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 13
·6182-6191
·
IF 6.97
Jinjin Ma,Qianting Yao,John A. McLeod,Lo-Yueh Chang,Chih-Wen Pao,Jiatang Chen,Tsun-Kong Sham,Lijia Liu
Inorganic lead halide perovskite CsPbX3 (X = Cl, Br, or I) nanocrystals are promising candidate materials for light-emitting devices and optoelectronics. Mn-Doped CsPbX3 is of particular interest, as the Mn-doping introduces an additional emission band, making this material a promising white-light emitter. In this study, Mn-doped CsPb(Br/Cl)3 nanocrystals are prepared at room-temperature and ambient pressure. The chemical environment of Mn, and the luminescence of these nanocrystals are analyzed in detail using X-ray diffraction (XRD), extended X-ray absorption fine structure (EXAFS), X-ray absorption near-edge structure (XANES) and X-ray excited optical luminescence (XEOL). Although the introduction of Mn does not alter the long-range order of the CsPbX3 crystal, it leads to a local lattice contraction with the bond length of Mn–X much shorter than Pb–X. We also find excitation energy-dependence in both the intensity and wavelength of the perovskite excitonic emission band, while only in intensity of the Mn emission band. Detailed fitting of the XEOL reveals that the perovskite emission band is dual-channel, and it is the excitation energy-dependent intensity variation of these two channels that drives the observed red-shift of the combined emission band. Our findings also confirm that the Mn emission band is driven by exciton-Mn energy transfer and clarify the Mn chemical environment and the luminescence mechanism in Mn-doped CsPb(Br/Cl)3 nanocrystals.
研究领域:
材料科学
·
光电子学
·
纳米技术
·
固体物理
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2021
·Vol. 9
·期 15
·5182-5189
·
IF 7.393
Liang Bao,Wenqiang Liu,Yonghua Chen,Yanbo Zhang,Yang Zhang
The local surface plasmon resonance effect induced by metal nanoparticles on perovskites provides a powerful approach to enhance the photoluminescence of such all-inorganic systems. Here, we show that the decoration of CsPb(Br/Cl)3 nanocrystals (NCs) with Au nanoparticles (NPs) leads to a significant enhancement of the blue emission centered at 465 nm, resulting in a photoluminescence quantum yield (PLQY) of up to 73%. Our simulations based on finite difference time domain (FDTD) analysis indicate that the distance between the Au NPs and CsPb(Br/Cl)3 NCs plays a crucial role in determining the local electric field intensity. Our data suggest that an excessive decoration of CsPb(Br/Cl)3 NCs with Au NPs can also reduce the PLQY, as a result of decreased coupling strength.
研究领域:
材料科学
·
光学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Yongfeng Liu,Yupeng Ying,Qingyu Xie,Zhaoju Gao,Xiuwen Shao,Min Zhou,Wei Pei,Xiaosheng Tang,Yusong Tu
Mixed-halide CsPb(Br/Cl)3 perovskite quantum dots (PeQDs) have attracted extensive attention in light-emitting diodes (LEDs), but their low photoluminescent efficiency and especially poor stability impede their practical applications. Here, we employ bifunctional didodecyldimethylammonium thiocyanide (DDASCN) with a pseudohalogen SCN– and branched DDA+ to obtain blue-emitting CsPbBr2Cl PeQDs. DDASCN significantly boosts the photoluminescence quantum yield to 92% by inhibiting nonradiative recombination. Importantly, DDASCN PeQDs show excellent stabilities against air, UV light, heat, and polar solvents. These improved performances were explained by density functional theory calculation, which shows that SCN– fills the Cl– vacancy by simultaneously binding with undercoordinated Pb2+ and Cs+, while DDA+ connects undercoordinated Br– and lies parallel to the PeQD core, leading to efficient passivation and a strong binding capacity. Finally, we achieved high-performance white LEDs by integrating our PeQDs, resulting in a color-rendering index of 92.9, a color gamut of 119.61%, and chromaticity coordinates of (0.33, 0.33). This provides an effective method to obtain efficient and stable CsPb(Br/Cl)3 PeQDs for practical applications.
研究领域:
材料科学
·
光电技术
·
纳米技术
·
光子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Functional Materials Letters
·
2024
·
IF 1.2
Zhuqing Sun,Yongxia Li,Haowen Bai,Shenghang Jin,Haibo Zhang,Guanying Cao
All inorganic lead halide cesium perovskite quantum dots (QDs) have attracted much attention due to their excellent luminescence properties, but further development is restricted by their stability and the existence of toxic element lead. In this paper, F/Mn-doped CsPb ( Br / Cl ) 3 QDs glass was prepared by melt quenching and heat treatment, with reduced Pb content effectively. The result shows that the spectrum of the QD glass is adjustable between 450 nm and 515.4 nm by changing the feeding ratio of Mn-Pb ion and heat treatment temperature. Moreover, the indraught of Mn 2 + effectively improves the PLQY of CsPb ( Br / Cl ) 3 QDs glass and serves as a red-emitting. The prepared composites not only maintain good fluorescence characteristics, but also greatly improve the stability of QDs. And successfully coupled with blue LED chips to synthesize WLED, Under 20 mA current, the color coordinate is (0.3446, 0.3389).
研究领域:
材料科学
·
纳米技术
·
光电子学
·
固体物理
·
无机化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2022
·Vol. 10
·期 22
·8815-8823
·
IF 8.067
Runda Guo,Weizhuo Zhang,Xin Li,Linyuan Lian,Hongting Chen,Chencheng Peng,Liang Sun,Shiyuan Liu,Jianbing Zhang,Lei Wang
Blue emitting CsPb(Br–Cl)3 perovskite nanoparticles (NPs) play an important role in optoelectronic applications. However, the synthesis of stable blue perovskite NPs with excellent photoluminescence quantum yield (PLQY) is still challenging. Here, a new strategy of conveniently using strontium halides and amine halides for simultaneous doping and surface passivation of CsPb(Br–Cl)3 perovskite NPs is proposed. Through experimental studies and calculations, it is found that divalent Sr2+ cations can partly replace the B-site Pb2+ ions in the lattice structure of perovskite NPs and cause a slight lattice contraction, not only passivating the defects but also providing chances for bluer NPs. As a result, the deep-blue CsPb(Br–Cl)3 perovskite NPs with PL emission centered at 455 nm and a high PLQY of 96% were obtained. In addition, a white light-emitting device (WLED) with the NPs as an emissive layer exhibited a maximum power efficiency of 76 lm W−1 with Commission International de L’Eclairage (CIE) coordinates of (0.33, 0.34). These findings provide fundamental insights into the excited state dynamics of colloidal cesium lead halide (CsPbX3) perovskite NPs that can be used as components of LEDs for practical applications.
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
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2021
·
IF 4.051
Zhihao Chen,Haiyang He,Zhuoqi Wen,Zhongjie Cui,Shiliang Mei,Dan Yang,Xian Wei,Wanlu Zhang,Fengxian Xie,Bobo Yang,Ruiqian Guo
Broadband emission Mn 2+ doped lead halide perovskites are deemed as promising phosphor materials for solid state white light-emitting-diodes (WLEDs). Herein, we report a facile gram-scale synthesis of Mn-doped CsPb(Br/Cl) 3 phosphors by doping MnCl 2 into CsPbBr 3 perovskite nanocrystals at room temperature. The obtained phosphors present dual-color emission with blue emission at 463 nm and red emission at 602 nm. Increasing MnCl 2 doping amount can enhance the red emission while more 3-Aminopropyltrimethoxysilane (APTMS) ligands can repress Mn related impurity and provide high stability. Further, two kinds of WLEDs (monocomponnet and two-component) are demonstrated. The monocomponent WLED exhibits warm white light under various driving currents (30 mA–150 mA), and the two-component WLED shows good chromatic performance close to ideal white light (0.33, 0.33), demonstrating their potential applications in WLED devices.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
Light-Science & Applications
·
2026
·Vol. 15
·期 1
·135
·
IF 24
Maimaitizi Hujiabudula,Ågren Hans,Chen Guanying
The development of pure-blue perovskite light-emitting diodes (PeLEDs) still lags behind that of green and red-emitting PeLEDs. Mixed halide (Br/Cl) perovskite nanocrystals (PeNCs) are commonly employed for blue emission but suffer from halide vacancies and ion migration. Here, we present a passivation strategy using the multifunctional fluorinated phosphonic acid molecule (1H,1H,2H,2H-heptadecafluorodec-1-yl)phosphonic acid (HFPA), which possesses active functional groups that improve the stability and electroluminescence performance of CsPb(Br/Cl) 3 NCs. The HFPA molecule is shown to interact with uncoordinated Pb 2+ on the PeNC surface through the phosphonate groups, concurrently establishing hydrogen bonds with adjacent halide ions. Moreover, the presence of fluorine atoms promotes ionic bond formation with the halide octahedra, thereby stabilizing the octahedral structure. The fabricated PeNC-LEDs exhibited a spectrally stable pure-blue emission peak at 467 nm, achieving a significantly improved external quantum efficiency (14.8%, 9-fold higher), maximum luminance (1052 cd·m -2 , 10-fold higher), and half-life (342 s, 13-fold higher) compared to the device fabricated with unmodified CsPb(Br/Cl) 3 NCs. Furthermore, the effective passivation of surface vacancies and stabilization of halogen ions by the HFPA molecules successfully suppressed ion migration in the PeNC-LEDs, thereby significantly enhancing the stability of the device.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Physics
·
2022
·
IF 11.021
Siqi Sun,Pei Jia,Qizhang Huang,Min Lu,Po Lu,Feisong Qin,Guang Sun,Yanbo Gao,Xue Bai,Zhennan Wu,Yu Zhang
Despite rapid development of perovskite nanocrystal (PeNC) light-emitting diodes (LEDs), it remains challenging to achieve efficient and stable blue PeLEDs , especially for pure-blue PeLEDs required for displays. Mixed halide CsPb(Br/Cl) 3 NC is a common strategy to achieve pure-blue emission, but suffers from low photoluminescence quantum yield (PLQY) and spectra instability. Here, a facile approach for the synthesis of high-quality pure-blue emitting CsPb(Br/Cl) 3 NCs is reported by introducing an organic sulfonate, phenyl trifluoromethanesulfonate (PTFMS), which works as an efficient surface passivator. As a result, the optimized PeNCs achieve a high PLQY of 85% and enhanced conductivity. Furthermore, the LED based on the optimized PeNCs is developed with pure-blue emission at 469 nm, which yields an external quantum efficiency (EQE) of 1.20% and luminance of 355 cd m −2 . More impressively, the device shows excellent spectra and operation stability under voltage bias , resulting from the suppressed ion migration channels by efficient defect passivation .
研究领域:
材料科学
·
光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）