Science China-Information Sciences
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2024
·Vol. 67
·期 5
·1-7
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IF 7.3
Zhang Yong,Wei Xin,Gao Lei,Zhao Weijie,Sun Changjiu,Wei Junli,Yuan Mingjian,Ni Zhenhua,Lu Junpeng,Liu Hongwei
The wider color gamut represents the better reproducibility of the real natural colors. Perovskite materials exhibit promising potential in full-color wide-gamut displays because of the wide tunability and high saturability of their photon emission. However, the full-color wide gamut (>100% Rec.2020) has not been constructed due to the lack of the extreme red primary color (∼700 nm). Herein, the widest color gamut is realized, wherein α -CsPbI 3 is used to generate the extreme red primary color. An in-situ encapsulation approach is advised to stabilize α -CsPbI 3 at room temperature by means of polyvinylpyrrolidone (PVP). The α -CsPbI 3 encapsulated by PVP (denoted as P-CPI) shows highly saturated (FWHM (full width at half maximum) ∼28 nm) and extremely (∼697 nm) red emission. The green emission is provided by P-CPBr (CsPbBr 3 with PVP) which is also synthesized using the universal in-situ encapsulation approach. With the assistance of a commercial GaN chip, the RGB gamut is extended to the widest (151% NTSC, 113% Rec.2020).
研究领域:
材料科学
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显示技术
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2022
·
IF 4.177
Xueying Chen,Yeqing Chen,Jie Huang,Chen Li,Zongming Ni,Kang Zhang,Mingxuan Cao,Ting Yu,Yan Chen,Xin He,Yang Li
Cubic-phase CsPbI3 perovskite nanocrystals (CsPbI3 NCs) are widely used as a promising luminescent material in optical devices such as light-emitting diodes and lasers due to their high photoluminescence quantum efficiency and excellent color purities. However, the CsPbI3 lattice is more likely to face the problem of phase transformation due to the poor thermodynamic stability, which would lead to the decrease of its photoluminescence quantum efficiency. In this work, α-CsPbI3 NCs were synthesized by the room-temperature dual-ligand-assisted re-precipitation method under the synergistic effect of n-octanoic acid (OTAC), oleylamine (OLA), and (3-aminopropyl)triethoxysilane (APTES). The anionic OTAC and cationic OLA ligands interacted with the Pb2+ and I–, respectively, on the surface of the α-CsPbI3 NCs to passivate the defects on the surface. By the adjustment to the volume ratio of the OTAC to OLA, the synergistic effects of the dual ligands inhibited the distortion of the octahedral [PbI6]4– and maintained the cubic perovskite structure of the α-CsPbI3 NCs. The hydrolysis of APTES into the silica layer would provide efficient environmental protection and maintain the cubic phase of α-CsPbI3 at room temperature. The α-CsPbI3 NCs not only produce strong red emission upon the UV excitation but also exhibit strong up-conversion luminescent properties upon the near-infrared excitation at a low excitation power laser of 1064 nm, showing dual-mode luminescent characteristics as a promising material for potential applications in optical devices.
研究领域:
材料科学
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光电子学
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纳米技术
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光子学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTAL RESEARCH AND TECHNOLOGY
·
2022
·Vol. 57
·期 10
·2100243
·
IF 1.599
Chunyu Sun,Xinzhan Wang,Pengfei Qiu,Xuejiao Mou,Wanbing Lu,Xiaoyun Teng,Guangsheng Fu,Wei Yu
Temperature-dependent photoluminescence (PL) properties of high quality cubic phase α-CsPbI 3 nanocrystals are investigated, and thermal transfer from free excitons to trapped excitons is observed. Free exciton recombination is the main origin of the high PL quantum yield (97%) at room temperature. Little change of PL peak energy is observed with decreasing temperature from 280 to 200 K, and it shifts from 1.84 to 1.81 eV in the region of 200 and 80 K. The PL peak intensity decreases with decreasing temperature first and then increases, and the minimum value is observed at 180 K. Two PL bands are obtained by Gaussian fittings in the PL spectra detected at different temperatures, and the high energy band is attributed to the emission of free excitons, while that for the low energy band is related to the transition of trapped excitons. The PL integrated intensity ratio of trapped exciton and free exciton transition increases from 0.18 to 2.10 with decreasing the temperature, which suggests that thermal transfer from free exciton to trapped exciton states leads to the dominant optical emission of trapped exciton recombination in the low temperature region.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2021
·
IF 3.512
Yu Ji,Jian-Bin Zhang,Hao-Ran Shen,Zhan Su,Hao Cui,Tao Lan,Jia-Qian Wang,Yu-Hui Chen,Lihui Liu,Kun Cao,Wei Shen,Shufen Chen
The wide application of CsPbI3 nanocrystals (NCs) is limited due to their poor phase stability. We reported that Mn2+-CsPbI3 NCs have better optical performance and phase stability. With a suitable Mn/Pb ratio (5.0%), Mn2+-doped α-CsPbI3 NCs exhibited the best stability under UV irradiation, ethanol addition, and heating. Under UV irradiation and addition of ethanol, photoluminescence (PL) intensities of CsPbI3 NCs could be only preserved up to 35% (22 min UV irradiation) and 10% (ethanol addition), respectively, whereas, Mn2+-doped CsPbI3 (5.0%) exhibited much improved stability, and their intensities could be preserved up to 70% (22 min UV) and 58% (ethanol), respectively. It should be noted that crystal-phase stability could be maintained at least 7 h even at 120 °C. We believe that the improved stability in extreme conditions for α-CsPbI3 NCs can be further applied to optoelectronic devices.
研究领域:
材料科学
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光电子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Chunyu Sun,Xinzhan Wang,Yanmei Xu,Wanbing Lu,Xiaoyun Teng,Guangsheng Fu,Wei Yu
CsPbI 3 nanocrystals (NCs) with photoluminescence quantum yield (PLQY) larger than 90% have been synthesized at different temperature regions, and the physical origins for high PLQY were investigated. HRTEM images show that cubic phase CsPbI 3 (α-CsPbI 3 ) is surrounded by hexagonal Cs 4 PbI 6 in the low temperature region, and the ratio of CsPbI 3 and Cs 4 PbI 6 increases with increasing the reaction temperature. The strong confinement effect of Cs 4 PbI 6 leads to the high PLQY (95%) of α-CsPbI 3 NCs when the reaction temperature is 120 °C. The confinement effect of Cs 4 PbI 6 is weakened with increasing reaction temperature, which leads to the decrease of PLQY at 140 °C. However, non-radiative recombination is suppressed due to the microstructure improvement with further increasing the reaction temperature, and PLQY as high as 97% is achieved at 180 °C. Stability testing shows that fast degradation of α-CsPbI 3 NCs occur in low reaction temperature region, and α-CsPbI 3 NCs with high PLQY can be stored in air for 90 days when the reaction temperature is 180 °C.
研究领域:
材料科学
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2023
·
IF 3.7
Huiling Zhu,Cuixia Hao,Xin Li,Yao Qi,Xuesong Zhu,Yucheng Miao,Rui Liu,Jianxu Ding
Black phase CsPbI3 quantum dots (QDs) have garnered significant research interest due to their remarkable properties in optoelectronic applications. However, their inherent instability and low phase stability often lead to an undesired transformation into an orthorhombic yellow phase. In this study, we propose an innovative approach to synthesize Ag+ doped CsPbI3 QDs in a nonvacuum environment. The theoretical calculations and experimental results demonstrate that Ag+ doping substantially increases the formation energy and Goldschmidt tolerance factor, resulting in an enhanced thermodynamic stability and photoluminescence quantum yield (PLQY). The resulting Ag+ doped CsPbI3 QDs exhibit an impressive PLQY of up to 97% and maintain their black phase for over 60 days. This novel nonvacuum synthesis approach holds great potential for producing high-quality all-inorganic perovskite CsPbX3 QDs. To demonstrate the practical applications, we fabricate a white light-emitting diode (WLED) using the Ag+ doped CsPbI3 QDs, achieving Commission Internationale de I’Eclairage (CIE) color coordinates of (0.36, 0.26). These findings highlight the broad prospects of CsPbI3 QDs in lighting and display technologies.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2019
·Vol. 29
·期 24
·1900991
·
IF 15.621
Keqiang Chen,Qiaohui Zhong,Wen Chen,Binghua Sang,Yingwei Wang,Tingqiang Yang,Yueli Liu,Yupeng Zhang,Han Zhang
Cubic phase CsPbI 3 (α-CsPbI 3 ) perovskite quantum dots (QDs) have received extensive attention due to their all-inorganic composition and suitable band gap (1.73 eV). However, α-CsPbI 3 QDs might convert to δ-CsPbI 3 (orthorhombic phase with indirect band gap of 2.82 eV) due to easy loss of surface ligands. In addition, commonly used long-chain ligands (oleic acid, OA, and oleylamine, OLA) hinder efficient charge transport in optoelectronic devices. In order to relieve these drawbacks, OA, OLA, octanoic acid, and octylamine are used as capping ligands for synthesizing high-quality α-CsPbI 3 QDs. The results indicate that these QDs exhibit excellent optical properties and long-term stability compared to QDs capped only with OA and OLA. Moreover, QDs with shorter ligands exhibit an enhanced charge transport rate, which improves the power conversion efficiency of photovoltaic devices from 7.76% to 11.87%.
研究领域:
材料科学
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光电子学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Rui Wang,Chenyu Shang,Qiqi Zhao,Qi Huang,Chenyang Liu,Wenli Xu,Rui Liu,Weiwei Zhang,Jianxu Ding
Cubic α-CsPbI3 is recognized as one of the most promising semiconductors for optoelectronic applications owing to its suitable band gap, excellent optoelectronic performance, and thermal stability. However, its phase instability from α to δ poses a significant obstacle for practical applications. How to stabilize α-CsPbI3 becomes a paramount issue. Here, we propose a strategy in which α-CsPbI3 nanocrystals (NCs) are in situ generated in the Cs4PbI6 single-crystal (SC) matrix through I ion migration, facilitated by its ultralow activation energy (0.104 eV). The existence of the I vacancy can promote ion migration and can increase the content of α-CsPbI3. As α-CsPbI3 NCs are generated in situ, the light yellow Cs4PbI6 SCs convert to black. The lattice of Cs4PbI6 twines outside of α-CsPbI3 NCs without a grain boundary and restricts the migration of I and Cs within the α-CsPbI3 lattice. This mechanism effectively stabilizes α-CsPbI3 for over 2 years without experiencing a phase transition. Such stable α-CsPbI3 NCs exhibit deep red emission (700 nm), a high exciton binding energy (55.5 meV), and a long carrier lifetime (176.9 ns). Furthermore, annealing at 320 °C for 12 h did not result in any damage. Additionally, white-light-emitting diodes (WLEDs) were fabricated using black Cs4PbI6 SCs and yellow phosphor YAG:Ce3+ under an atmospheric environment and realized white emission. The WLEDs maintain approximately 86% luminescence after 18 days or under continuous operation for 12 h, demonstrating high stability and eliminating the need for short-wavelength blue chips. Overall, the α-CsPbI3 NCs deviating from Cs4PbI6 SCs offer an approach to realize highly efficient light-emitting diode applications.
研究领域:
材料科学
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光电技术
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2026
·
IF 4.9
Zhangwei Guo,Zhuolu Li,Yi Wu,Song Wang,Jiaxin Rui,Zhaogang Teng,Lihong Qi,Kai Pan
One-dimensional (1D) CsPbI 3 nanomaterials with long carrier lifetimes, high carrier transport efficiencies, and anisotropic optical properties show promising applications in lasers and photodetectors. In this study, monodisperse Cs 4 PbI 6 nanocrystals (NCs) (12.3 nm) were first synthesized by thermal injection. The addition of deionized water to this solution then induced the conversion of Cs 4 PbI 6 NCs into CsPbI 3 NCs, followed by their self-assembly into CsPbI 3 nanorods (NRs) with controllable aspect ratios. This process leverages the high solubility of CsI in water, which drives the decomposition of Cs 4 PbI 6 and the formation of CsPbI 3 NCs, which subsequently self-assembled and fused into CsPbI 3 NRs. CsPbI 3 NRs synthesized under the optimal reaction conditions were characterized by uniform size and regular morphology, with a diameter of 12.4 nm and length of 52.5 nm. XRD analysis shows that these monodisperse CsPbI 3 NRs, in contrast to 1D CsPbI 3 nanomaterials synthesized by the conventional thermal injection method, possess a typical cubic phase (α-phase) structure and exhibit good red light emission properties. Due to kinetic limitations during rapid nucleation at the nanoscale, the system preferentially forms the metastable α-CsPbI 3 , characterized by a low nucleation barrier and strong structural inheritance, rather than the thermodynamically stable δ-phase. Compared with NRs obtained under other reaction conditions, the optimal CsPbI 3 NRs demonstrate stronger fluorescence intensity and longer fluorescence lifetime. The CsPbI 3 NRs synthesized under the optimal conditions (2 mL water, 5 min) exhibit a strong first exciton absorption peak at 450 nm, a narrow photoluminescence emission peak at 695 nm, a lifetime as high as 239.9 ns, and a higher exciton binding energy (72.5 meV), ensuring efficient exciton emission at room temperature. Compared with NRs obtained under other reaction conditions, these optimally synthesized NRs demonstrate stronger fluorescence intensity and longer fluorescence lifetime. This work presents a reliable method for the controlled synthesis of 1D α-CsPbI 3 NRs, offering a theoretical and experimental foundation for the application of halide perovskite nanorods in high-performance optoelectronic devices.
✓ 已验证
DOI
高影响因子
Journal of the American Chemical Society
·
2019
·
IF 14.695
Ji-Song Yao,Jing Ge,Kun-Hua Wang,Guozhen Zhang,Bai-Sheng Zhu,Chen Chen,Qun Zhang,Yi Luo,Shu-Hong Yu,Hong-Bin Yao
Cubic phase CsPbI3 quantum dots (α-CsPbI3 QDs) as a newly emerging type of semiconducting QDs hold tremendous promise for fundamental research and optoelectronic device applications. However, stable and sub-5 nm-sized α-CsPbI3 QDs have rarely been demonstrated so far due to their highly labile ionic structure and low phase stability. Here, we report a novel strontium-substitution along with iodide passivation strategy to stabilize the cubic phase of CsPbI3, achieving the facile synthesis of α-CsPbI3 QDs with a series of controllable sizes down to sub-5 nm. We demonstrate that the incorporation of strontium ions can significantly increase the formation energies of α-CsPbI3 QDs and hence reduce the structure distortion to stabilize the cubic phase at the few-nanometer size. The size ranging from 15 down to sub-5 nm of as-prepared stable α-CsPbI3 QDs allowed us to investigate their unique size-dependent optical properties. Strikingly, the few-nanometer-sized α-CsPbI3 QDs turned out to retain high photoluminescence and highly close packing in solid state thin films, and the fabricated red light emitting diodes exhibited high brightness (1250 cd m–2 at 9.2 V) and good operational stability (L50 > 2 h driven by 6 V). The developed cation-substitution strategy will provide an alternative method to prepare uniform and finely size-controlled colloidal lead halide perovskite QDs for various optoelectronic applications.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2022
·Vol. 24
·期 21
·3852-3858
·
IF 3.756
Runze Guo,Yufeng Liu,Yongzheng Fang,Zhifu Liu,Langping Dong,Lei Wang,Wenyao Li,Jingshan Hou
CsPbI3 has the least chemical stability among the CsPbX3 (X = Cl, Br, and I) perovskite nanocrystal (PNC) family due to its thermodynamically metastable characteristics, thus limiting the development of all-inorganic perovskite white-light devices. The current study presents a microfluidic-based continuous large-scale fabrication of CsPbI3-mesoporous SiO2 (CPI/m-SiO2) nanocomposites to solve the problem of large-scale continuous production of stable, repeatable, high-quality perovskite NCs. The results reveal that the chemical stability and thermal quenching behaviour of CPI PNCs were greatly improved due to the protection of mesoporous silica. Particularly, the water resistance property of CPI/m-SiO2 nanocomposites improved two-fold compared to that of noncomposite CPI PNCs, and the thermal stability of the CPI/m-SiO2 nanocomposites improved nearly three-fold at 373 K when compared with that of the noncomposite CPI NCs. Furthermore, photons were speculated to transmit along with the pores and channel structure of m-SiO2 to reduce photon absorption between NCs. Moreover, the microfluidic technology can operate continuously and is precisely controllable, enabling large-scale nanocomposite synthesis with uniform size and shape.
研究领域:
材料科学
·
光电子学
✓ 已验证
DOI
高影响因子
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