APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Zhenyu Zhang,Ning Wang,Xingzi Wang,Zheng Zhao,Chen Dong,Xianmin Tan,Yuanyuan Zheng,Zongyu Feng,Xiangxi Zhong,Juanyu Yang,Xiaowei Huang
With the linewidth of integrated circuits has progressively narrowed, imposing higher demands on the chemical mechanical polishing (CMP) process. Cerium oxide nanoparticles are widely used as abrasives in CMP, with their physical structure and the surface content of Ce 3+ ions and oxygen vacancies directly affecting their CMP performance. Here in, we synthesized La/Pr/Nd doped CeO 2 with the porous self-assembled spherical structures. Doping with La/Pr/Nd reduced the grain size of cerium oxide, increased its specific surface area, decreased the pore size, and increased the pore volume. HR-TEM analysis shows that the porous self-assembled spherical CeO 2 primarily exposes the (111) crystal facet. Additionally, the density functional theory (DFT) calculation, XPS, H 2 -TPR and XANES analyses shown that doping of La/Pr/Nd facilitated the formation of oxygen vacancies and increased the Ce 3+ content on the (111) crystal facet of the CeO 2 . La atoms are more likely to stabilize on the CeO 2 (111) surface compared to Pr and Nd atoms. The CMP results indicated that, The La-CeO 2 exhibited a higher MRR of 338 ± 7.54 nm/min, which is a 35 % increase compared to p-CeO 2 , and achieved superior surface roughness ( Ra = 0.201 ± 0.010 nm).
研究领域:
材料科学
·
纳米技术
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DOI
高影响因子
DALTON TRANSACTIONS
·
2021
·Vol. 51
·期 2
·645-654
·
IF 4.39
Qinghong Meng,Guoying Zhao,Qi Zhu,Xiaodong Li,Xudong Sun,Ji-Guang Li
Synergistic doping of the metastable Gd3Al5O12:Ce garnet with a Ca2+/Hf4+ pair and Sc3+ to form Gd2.97−xCaxHfxScyAl3O12:0.03Ce (x = 0.5–2.0, y = 0.0–1.5, x + y = 2.0) solid solution was conducted for the structural stabilization and photoluminescence manipulation. The site selection of Ca2+/Hf4+/Sc3+ dopants and the effects of doping on the crystal structure, local coordination, band structure and Ce3+ luminescence were revealed in detail with the results of XRD, Rietveld refinement, TEM, and UV-Vis/photoluminescence spectroscopy. A decrease in Ca2+/Hf4+ and an increase in the Sc3+ content were observed to shrink the lattice, widen the bandgap of the garnet host, red-shift the excitation/emission wavelength, broaden the emission band and shorten the fluorescence lifetime of Ce3+. The spectral changes were rationalized by considering the local coordination and crystal field splitting of the Ce3+ 5d energy level. Application of typical Gd0.97Ca2Hf2Al3O12:0.03Ce (x = 2.0, y = 0) cyan and Gd2.47Ca0.5Hf0.5Sc1.5Al3O12:0.03Ce (x = 0.5, y = 1.5) greenish-yellow phosphors in w-WLED lighting produced low correlated color temperatures of ∼3842 and 3514 K, high color rendering indices of ∼88 and 93 and favorable luminous efficacies of ∼32.9 and 14.7 lm/W under the excitation of 395 nm n-UV and 450 nm blue LED chips, respectively.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Advances
·
2022
·Vol. 3
·期 16
·6529-6538
·
IF 0
Shuqin Chang,Jipeng Fu,Kaina Wang,Xuan Sun,Yingying Ma,Guangcan Bai,Guoquan Liu,Yonggang Wang,Mingxue Tang
Although near-infrared phosphors have been widely reported, discovering efficient red-emitting phosphor materials with superior photophysical properties and high color quality is still a challenge for optimizing white light-emitting diodes (wLEDs). In this regard, a series of Eu2+ and Ce3+ doped SrS phosphors were synthesized via a one-step solid-state method at 1100 °C. The SrS:(Eu2+)n and SrS:(Ce3+)0.01,(Eu2+)n powders show substantial spectral broadening (∼80 nm) along with a significant thermal quenching resistance. The phosphor of SrS:(Eu2+)0.002 exhibits the most intense luminescence with a high color purity of 99.94% and an afterglow luminescence lasting several seconds. The luminescence intensity and peak position were modulated by the resonance-type energy transfer from Ce3+ to Eu2+ ions, which is proposed to follow the dipole–dipole interaction mechanism by Dexter's energy transfer theory and Reisfeld's approximation. The outstanding photoluminescence properties of Eu2+ are attributed to the nephelauxetic effect and crystal field splitting of rock-salt. The wLED device of SrS:(Eu2+)0.05 packaged with a blue chip and (Sr,Ba)2SiO4:Eu2+ shows a super-high color rendering index of 87.9, suggesting great potential for superior luminescence and promising wide applications.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
CHEMICAL PHYSICS LETTERS
·
2021
·
IF 2.328
Jiazhi Li,Zhidong Ma,Fu Wang,Zhaofeng Wang
In this work, submicro-sized Y 3 Al 5 O 12 :Ce 3+ particles were synthesized via a coprecipitation method. When mechanical stimuli are applied, the submicro-sized Y 3 Al 5 O 12 :Ce 3+ can exhibit intense greenish-yellow mechanoluminescence. Different from the bulk Y 3 Al 5 O 12 :Ce 3+ synthesized by conventional solid-state method, the mechanoluminescence of the submicro-sized Y 3 Al 5 O 12 :Ce 3+ exhibits a trap-dependent behavior. The distinct spectral characteristics between photoluminescence and mechanoluminescence further suggest that distorted Ce 3+ sites could be generated under mechanical stimuli, and therefore the mechanoluminescent mechanisms of the submicro-sized Y 3 Al 5 O 12 :Ce 3+ are revealed.
研究领域:
材料科学
·
发光材料
·
力致发光
·
纳米材料合成
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2026
·Vol. 18
·期 32
·44222-44235
·
IF 7.8
Wang Xiyao,Liang Jiaju,Ji Huiyu,Zhang Jian,Lin Lin,Liang Hengnan
Optical manometry is essential in diamond anvil cell experiments, motivating pressure-sensitive phosphors that provide robust broadband readouts over a wide pressure range. Here we report a Ce 3+ -activated CaZrO 3 perovskite phosphor with a low dopant level of about 0.40 atom % Ce quantified by EDS, and we evaluate its pressure-dependent luminescence response. Powder XRD and SEM–EDS confirm a single-phase CaZrO 3 host and successful incorporation of the Ce activator. Temperature-dependent photoluminescence and lifetime measurements reveal that the material exhibits good thermal stability. Under compression up to 45 GPa, the broadband Ce 3+ 5d–4f emission exhibits an almost linear redshift of the band centroid with dλ/d P about 2.45 nm GPa –1 and a concurrent broadening of FWHM with dFWHM/dP about 1.15 nm GPa –1 . In parallel, the CIE 1931 chromaticity coordinates derived from the full emission spectrum evolve regularly with pressure, enabling a continuous color change from blue to green and offering a convenient visual readout. High-pressure Raman spectra indicate a structural transition near 30 GPa, consistent with synchrotron XRD reports for CaZrO 3 , yet no discontinuity is observed in the pressure dependences of the luminescence parameters. First-principles calculations suggest that compression is mainly accommodated by ZrO 6 octahedral tilting and anisotropic polyhedral compression, whereas the local Ce-O crystal-field environment evolves smoothly, accounting for the continuous optical response through the transition. These results establish CaZrO 3 :Ce 3+ as a wide-range, multi-parameter optical manometer for high-pressure calibration at room temperature.
✓ 已验证
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2026
·
IF 6
Yuwen Liu,Chengwen Bin,Cheng Sun,Sheng Jiang,Jie Wang
Research on Aurivillius ceramics mainly focuses on perovskite-like slabs, whereas fluorite-like (Bi 2 O 2 ) 2+ layers are often regarded as passive. Here, Ce 3+ /La 3+ -modified CaBi 2 Nb 2 O 9 -based ceramics were designed to clarify how engineering the (Bi 2 O 2 ) 2+ layers affects cross-layer structural coupling and electromechanical response. Ce 3+ /La 3+ incorporation weakens orthorhombic distortion and induces tetragonal-like evolution while maintaining the Aurivillius framework. Raman and XPS results further demonstrate that this modification simultaneously alters the local Bi–O environment, A-site Ca 2+ coordination, NbO 6 octahedral distortion, and defect chemistry, confirming pronounced coupling between the fluorite-like layers and perovskite slabs. In addition, Ce 3+ /La 3+ incorporation suppresses Bi volatilization, improves densification and optimizes the domain morphology. As a result, the ceramic with x = 0.05 exhibits an enhanced piezoelectric coefficient d 33 of 15.9 pC/N while retaining a high Curie temperature of 921 °C. This work demonstrates that targeted engineering of the (Bi 2 O 2 ) 2+ layers is an effective route for regulating cross-layer coupling and improving the performance of high-temperature Aurivillius piezoceramics.
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Shigang Hu,Mulan Liu,Song Wang,Shaobing Wu,Dong Zhu
The use of InGaN/GaN blue light chips to excite surface-coated yellow phosphors is one of the common strategies for the preparation of WLEDs. In this study, a series (Y,Gd) 3 Al 5 O 12 ((Y,Gd)AG) phosphors doped with different concentrations of Ce 3+ were prepared using the co-precipitation method. The yellow light emission intensity of the phosphor reaches its maximum at a Ce 3+ concentration of 5 %. This observation is consistent with theoretically quenching concentration (4.7 %) calculated by the Stern - Volmer formula and the optimal quantum yield (69.18 %). Further research indicates that the emission efficiency of the sample remains almost same after 7 days and maintained room temperature efficiency of 67 % at 400 K, with a color temperature value of 2662 K and a CRI value superior to that of YAG:Ce. The results TR-PL tests showed that when the concentration of Ce 3+ doping was gradually increased up 5 %, the distance between the emission centers becomes shorter, which leads to a decrease in the emission lifetime and thereby improves the luminous efficiency. When the concentration exceeds 5 %, concentration quenching leads to an increase in non-radiative processes, and this quenching mechanism is identified as energy transfer between Ce 3+ - Ce 3+ ions. This result provides ideas for obtaining highly efficient yellow phosphors, and also provides a realization path for improving the performance of CCTs and CRIs in WLEDs.
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DOI
高影响因子
Materials
·
2019
·Vol. 12
·期 9
·1501
·
IF 2.972
Hongdan Zhang,Ludan Zhu,Jun Cheng,Long Chen,Chuanqi Liu,Shuanglong Yuan
In recent years, all-inorganic lead-halide perovskites have received extensive attention due to their many advantages, but their poor stability and high toxicity are two major problems. In this paper, a low toxicity and stable Cs2SnCl6double perovskite crystals were prepared by aqueous phase precipitation method using SnCl2as precursor. By the XRD, ICP-AES, XPS, photoluminescence and absorption spectra, the fluorescence decay curve, the structure and photoluminescence characteristics of Ce3+-doped and undoped samples have been investigated in detail. The results show that the photoluminescence originates from defects. [SnSn4+2++VCl] defect complex in the crystal is formed by Sn2+substituting Sn4+. The number of defects formed by Sn2+in the crystal decreases with Ce3+content increases. Within a certain number of defects, the crystal luminescence is enhanced with the number of [SnSn4+2++VCl] decreased. When Ce3+is incorporated into the crystals, the defects of [Ce3+Sn4++VCl] and [SnSn4+2++VCl] were formed and the crystal show the strongest emission. This provides a route to enhance the photoluminescence of Cs2SnCl6double perovskite crystals.Keywords:lead-free perovskite;Cs2SnCl6;doping;photoluminescence
研究领域:
材料科学
·
光电
·
固体物理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMISTRY OF MATERIALS
·
2020
·
IF 9.567
Shihai You,Shuxing Li,Yongchao Jia,Rong-Jun Xie
Traditionally, phosphors are developed by doping activators on standard crystallographic sites of selected inorganic hosts, thus enabling the prediction of their luminescence with some empirical models or theoretical calculations. Here, we propose the idea of interstitial site engineering as a totally different way to design phosphors with promising properties. In detail, a red-emitting phosphor La3Si6N11:Ce3+,Al3+ was developed by engineering the interstitial Ce3+ site, which produces an unusual red emission band (λem = 600–665 nm) under blue light excitation. The origin of this red emission was assigned from the first-principle calculation to the Ce3+ ion occupying the [Si8N8] void in the c∼1/2 layer of which the calculated transition energies matching with experiment within 0.1 eV. Such an interstitial Ce3+ site was created as a charge compensator for the aliovalent substitution of Si4+ by Al3+ ions. The red-enhanced La3Si6N11:Ce3+,Al3+ phosphor showed great potentials for improving the optical quality (i.e., color temperature and color rendition) of laser-driven white light. This work indicates that the interstitial site engineering is an efficient way for generating new luminescence centers and opens up an avenue for designing phosphors with appealing properties.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ChemCatChem
·
2024
·
IF 3.8
Pengchao Ren,Zhenzhou Zhang,Tingting Hu,Zhihui Fan,Shanshan Dang,Sifan Cheng,Weifeng Tu,Yi-Fan Han
Graphical The apparent rate coefficients for CH 3 OH synthesis from CO hydrogenation are a single-valued function of the CO 2 -to-CO ratio in the contacting gas phase, because this ratio determines the extent of surface oxidation of Ce 2 O 3 to CeO 2 , the relative abundance of surface Ce 3+ , and in turn the density of Cu 0 -Ce 3+ sites pair on the working Cu/CeO 2 catalyst. This study investigated the dynamic structure of a working Cu/CeO 2 catalyst and its catalytic consequences for CH 3 OH synthesis via CO hydrogenation by kinetics, high-precise chemical titration, and a series of in situ X-ray spectroscopies. We have revealed that the apparent rate coefficients for CH 3 OH synthesis from CO hydrogenation are a single-valued function of the CO 2 -to-CO ratio in the contacting gas phase. This ratio determines the extent of surface oxidation of Ce 2 O 3 to CeO 2 , the relative abundance of surface Ce 3+ and Ce 4+ sites, and in turn, the density of Cu 0 -Ce 3+ sites pair on the working Cu/CeO 2 catalyst, although the chemical state of Cu and elemental distribution of both Cu and Ce were insensitive to the ratio. The reactivity of CH 3 OH formation and the Cu 0 -Ce 3+ sites decrease monotonously with an increase in the CO 2 -to-CO ratio. The direct connection of the reactivity and the oxidant-to-reductant ratio appears to be general for heterogeneous catalysis, for which the oxidant oxidizes metal atoms. In contrast, the reductant scavenges surface oxygen atoms, thus dictating the density of surface sites and their thermodynamic activities.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Yubin Wen,Yufu Liu
Typical high-entropy fluorite oxides with five metal cations have exhibited improved thermomechanical properties . In this work, we have successfully prepared single-phase high-entropy (Zr 0.2 Ce 0.2 Hf 0.2 Y 0.2 Al 0.2 )O 2-δ fluorite oxides through the combination of sol-gel method and calcination , using metal nitrate/chloride, citric acid and absolute ethanol as the primary raw materials. A series of characterizations were employed for chemical, morphological and structural analysis of the calcined products. The five cationic elements were shown to be uniformly distributed in the nearly pure fluorite oxide without apparent segregation at the micro/nano-meter scales after 1500 °C calcination. Annealing and water quenching within the test temperature range did not witness any appreciable phase transition. It is revealed that the concentration of Ce 3+ in Ce ions reaches 33.84% and δ is equal to 0.234, yielding a nominal composition of (Zr 0.2 Ce 0.2 Hf 0.2 Y 0.2 Al 0.2 )O 1.766 . Cation and anion configurational entropy were found to be 1.609 R and 0.722 R, respectively, where R is the ideal gas constant, for a sum of the total configurational entropy of 2.331 R in the high-entropy system. Line defects inside the crystals and 3 types of crystalline boundary structures have been observed and identified among the mostly atomically sharp grain boundaries.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
MATERIALS SCIENCE FORUM
·
2011
·
IF 0
Jun Zhang,Xiao Ting Shi,Wei Guo,Zhong Zhang,Hong Yang
The structural transition of DNA double-stranded induced by Ce3+ or Mg2+ ions was investigated in this paper. By atomic force microscopy, different types of condensed DNA structures were observed at the presence of Ce3+ or Mg2+ ions. The results show that there are some differences between rare earth ions and alkaline earth metal ions in the DNA condensation process.
研究领域:
生物化学
·
分子生物学
·
纳米技术
✓ 已验证
DOI
危险品化学品经营许可证（带存储）