CORROSION SCIENCE
·
2026
·
IF 10.3
Kangran Wei,Mengen Hu,Chengwan Yang,Xian Dang,Ming Li,Yuhan Zhu,Yanhui Chu,Xiaoye Hu,Liwen Yan,Zhulin Huang
Although Ta 4 HfC 5 ceramic has a highest melting point reported, it ablates rapidly in oxidative environment because Ta 2 O 5 has a low melting point of 1872 °C. In this work, ultrafine Ta-Hf-C solid-solution powders (49∼70 nm) with tunable Ta/Hf ratio were synthesized via a solvothermal route combined with carbothermal reduction using a liquid-phase precursor. Ta-Hf-C solid-solution bulks with relative densities of 98–99% were subsequently obtained by an ultra-fast pressure sintering technique. The effects of Ta/Hf ratio on densification behavior, mechanical properties, and oxidation–ablation resistance were systematically evaluated. Among all compositions, the 1TaC-4HfC ceramic exhibited the lowest mass and linear ablation rates of 0.422 mg/s and 14.237 μm/s after 120 s exposure to laser irradiation at a heat flux of 30 MW/m 2 , with a surface temperature up to 3800 °C. During ablation, a dense protective oxide layer formed through the reaction between HfO 2 and Ta 2 O 5 , generating Hf 6 Ta 2 O 17 coatings on the HfO 2 framework, while molten Ta 2 O 5 acted as a liquid bonding phase to wet and integrate the oxide phases with the residual carbide skeleton. This synergistic HfO 2 /Hf 6 Ta 2 O 17 /Ta 2 O 5 composite structure effectively suppressed oxygen permeation and enhanced high-temperature stability above 3000 °C.
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2018
·Vol. 30
·期 1
·015705
·
IF 3.404
Jianjun Wang,Yingxiong Zhang,Huilian Hao,Wenzhong Shen
Stable luminescent colloidal silicon (Si) nanocrystals (NCs) with sufficient surface protection are prepared through femtosecond laser ablation in organic solvent containing diverse concentrations of HF solution. The average size of Si NCs shows the decreasing tendency from 6.5 to 2.7 nm when the concentration of HF varies from 0 to 11.1 vol% (volume ratio). In line with the structural evolution, UV–visible absorption, photoluminescence (PL) excitation spectra, and time-resolved PL, we propose that room temperature blue emission peaks at 412 and 440 nm originate from alkyl-related radiative recombination centers. The enhanced PL quantum yield of colloidal Si NCs from 16.3% to 76.5% has been attributed to the effective passivation and suppression of non-radiative defect centers with increasing HF concentration from 0 to 11.1 vol%.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Xingxing Li,Yan Zhu,Nan Zhang,Yansheng Gong,Rui Wang,Huanwen Wang,Jun Jin,Ling Zhao,Beibei He
The development of symmetrical solid oxide fuel cells (SSOFCs) faces a significant challenge in designing electrode materials that exhibit both high activity and stability. In this work, a novel layered perovskite oxide symmetric electrode material PrBaFe 1.8 Hf 0.2 O 5+δ (PBFH) for SSOFCs is proposed and synthesized. Doping Hf at the B-site of PrBaFe 2 O 5+δ (PBF) improves the stability in reducing atmosphere and increases the concentration of oxygen vacancies . Furthermore, a small amount of RuO x is deposited by atomic layer deposition (ALD) onto PrBaFe 1.8 Hf 0.2 O 5+δ scaffold as symmetric electrodes. The surface modification of ALD-RuO x significantly boosts the catalytic activity for both fuel oxidation and oxygen reduction, simultaneously. Compared to PBF electrodes, the interfacial polarization resistances of RuO x -PBFH decrease to 0.77 Ω cm 2 under H 2 /Ar and 0.021 Ω cm 2 under air atmosphere at 800 °C, respectively. At 800 °C, SSOFCs equipped with RuO x -PBFH symmetric electrodes exhibit a high peak power density of 0.85 W cm −2 and 0.41 W cm −2 using humidified hydrogen and propane as fuels, respectively. Moreover, the RuO x -PBFH electrode demonstrates long-lasting performance, displaying high resistance against coking. These findings reveal a facile ALD approach for tailoring symmetric perovskite electrodes, offering robust and efficient electrocatalysis with efficient noble metal utilization.
研究领域:
材料科学
·
电化学
·
能源材料
·
固体离子学
·
催化化学
·
功能陶瓷
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Mei Yan,Ru-Ling Tang,Wei Xu,Wenlong Liu,Sheng-Ping Guo
Zirconium/hafnium fluorides have recently been recognized as potential nonlinear optical (NLO) materials with short ultraviolet (UV) cutoff edges, which is significant in laser science and industry. The synthesis of noncentrosymmetric (NCS) materials based on centrosymmetric (CS) compounds by an isovalent cation substitution-oriented design is an emerging strategy in the NLO territory. Here, two isostructural and novel fluorides, CaBaMF8 (M = Zr (1), Hf (2)), have been synthesized through the combination of alkaline earth metals, zirconium/hafnium, and fluorine elements. They feature zero-dimensional and CS structures composed by an isolated MF8 (M = Zr, Hf) dodecahedron and dissociative Ca2+ and Ba2+ cations, and they display short UV cutoff edges (<200 nm) as well. Two three-dimensional fluorides Li2CaMF8 (M = Zr (3), Hf (4)) are obtained by replacing Ba with alkali metal Li atom, which not only represent phase-matchable second-harmonic-generation activities (0.36, 0.30× KH2PO4 (KDP)) at 1064 nm but also maintain short UV cutoff edges with high reflectance. This work has largely enriched the family of NCS zirconium/hafnium fluorides reaching the short UV region.
研究领域:
材料科学
·
无机化学
·
光学材料
·
晶体工程
·
非线性光学
✓ 已验证
DOI
高影响因子
FUEL
·
2026
·
IF 7.5
Muhammad Kashif Majeed,Rashid Iqbal,M.Umar Majeed,Muhammad Akram,M.Zeeshan Ashfaq,Adil Saleem
Heterogeneous catalysis is highly desirable for the self-condensation of cyclohexanone, an important step in producing intermediates for fine chemicals and polymers. Conventional methods often rely on toxic reagents and long reaction times, limiting their industrial viability. In this study, Zr- and Hf-based metal–organic frameworks (UiO-66 and NUS-6) were developed as efficient, environmentally friendly catalysts for the self-condensation of cyclohexanone. Their high surface area and hierarchical porosity, combined with bifunctional Brønsted and Lewis acid sites introduced through partial linker substitution, enable excellent catalytic performance. UiO-66(Zr) achieved 81 % conversion in 6 h and 98 % in 48 h, while NUS-6(Zr) reached 85 % and 86 % under the same conditions, with high selectivity toward the desired dimer products. The catalysts also showed strong thermal stability and reusability, maintaining activity at elevated temperatures. This work demonstrates a sustainable catalytic pathway for cyclohexanone dimerization, avoiding corrosive chemicals while offering both efficiency and selectivity.
✓ 已验证
产品关联
DOI
高影响因子
ACTA MATERIALIA
·
2026
·
IF 9.3
Sai Liu,Xiaopeng Hu,Guangsheng Chen,Shenxiang Luo,Yu Zou,Jinwei Guo,Wang Zhu
Despite their promise as candidates for thermal barrier coatings (TBCs), the engineering application of A 6 B 2 O 17 ( A = Hf, Zr; B = Ta, Nb) ceramics is currently limited by a lack of comprehensive understanding regarding their CMAS corrosion behavior and underlying mechanisms. This paper addresses this gap by elucidating the governing effects of compositional modulation and corrosion conditions on the CMAS corrosion performance of these ceramics, integrating experimental and first-principles theoretical approaches. The results demonstrate that while all compositions exhibit similar corrosion products and resistance mechanisms, A 6 Ta 2 O 17 (particularly Hf 6 Ta 2 O 17 ) displays superior corrosion resistance. This enhanced performance is attributed to a combination of factors, including its exceptional thermodynamic stability, reduced Ca 2+ diffusivity, the significant barrier effect of its dense corrosion product layer, and stronger interfacial bonding strength. Corrosion-induced spallation in Zr 6 B 2 O 17 primarily stems from two factors: the phase transformation of ZrO 2 and an inherently weak interfacial bonding strength. Moreover, while an elevated Ca/Si ratio increases the aggressiveness of CMAS melts, the formation of a dense corrosion product layer on the ceramic surface effectively mitigates this detrimental effect.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Xin-zheng Jin,Zhen-yu Yang,Chen-hui Huang,Jing-hui Yang,Yong Wang
Recently, the miniaturization of microelectronics has proposed a more urgent demand for the multi-functionalization of packaging materials. Here, a PEDOT:PSS/MXene/PEG composite, which is prepared by vertical directional freezing and vacuum infiltrating, integrates the function of heat management & EMI shielding into single packaging material. The melting & cooling enthalpy (237.6 & 236.1 J g −1 ) and the phase transition temperature of composite are enhanced synchronously for the first time. The zigzag modification of polyethylene glycol (PEG) crystal is induced by poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). The rest of crystal with (7/2) helix conformation packs preferentially along the (1 2 0) plane. The stability of the melting composite is enhanced. The PEG leakage is less than 0.66 %, and over 80 % dimension is maintained under the pressure of 1.88 kPa. The composite shows excellent photo-thermal (η = 94.9 %) and electro-thermal (t η = 7.86) conversion performances. The EMI shielding mechanism is reflection-dominated and the total EMI shielding effectiveness (SE T ) of composite is 29.8 dB at the framework content as low as 1.22 wt%, which is the relatively low filler content and the highest enthalpy efficiency among the reported composites with the equivalent SE T . The HF-band shielding capability of composite is verified by the Tesla kit. The assembled heterogeneous asynchrony photo-thermal-electric conversion system identifies its potential application on photo-thermal converters and heat buff. The HF-band & X-band (Sub-6G) EM waves shielding and heat management in microelectronics can be achieved simultaneously by applying this composite.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Huilin Lun,Yi Zeng,Xiang Xiong,Houbu Li,Ziming Ye,Xiaoxu Liu
This work introduces fabricating single-phase ternary-anion carbide solid solution via solid-state diffusion of B and N. Initially, non-stoichiometric (Zr,Hf,Ti)C x with carbon vacancies was synthesized by modified spark plasma sintering. Then, using B 2 O 3 and g -C 3 N 4 as sources, (Zr 0.3 Hf 0.5 Ti 0.2 )(C 0.87 B 0.03 N 0.07 ) with face-centered-cubic structure was produced via B diffusion at 1100 °C and N diffusion at 1600 °C. Trace B (0.23 wt%) and N (0.71 wt%) in (Zr 0.3 Hf 0.5 Ti 0.2 )(C 0.87 B 0.03 N 0.07 ) was found to significantly enhance the oxidation resistance (higher onset temperature 520 ± 3 °C (particle size 2.5 ± 1.3 μm) than 475 ± 3 °C of (Zr 0.3 Hf 0.5 Ti 0.2 )C 0.85 and improve structural stability with more negative binding energy.
研究领域:
材料科学
·
陶瓷
·
固态化学
·
高温材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2025
·
IF 3.8
Qiqiang Zhang,Lei Cao,Bo Peng,Hui Zhang,Xingyuan San,Yanchun Zhou,Man Jiang,Qingguo Feng,Chunfeng Hu
MAX phase ceramics, as a family of ternary layered ceramics, have received a lot of attention in the past decade due to their potential as precursors for two-dimensional transition metal carbides. However, due to complex multi-component metallurgical reactions, multicomponent MAX phase ceramics have always faced difficulties in purification and homogenization. This paper identifies a new strategy for synthesizing multicomponent MAX phase ceramics that can eliminate these synthesis difficulties. This path utilizes low-temperature (below 1000°C) stable Ti 2 AlC and carbide powder as initial materials to simplify complex multi-component reactions into a one-step reaction, successfully achieving high purity and precise doping ratio. As an example, four novel doped MAX phase ceramics, Ti 2 MAlC 2 (M = Nb, Ta, W) and Ti 2 HEAlC 2 (HE = 1/7Ti, 1/7V, 1/7Zr, 1/7Nb, 1/7Hf, 1/7Ta, 1/7 W) were successfully synthesized using this method. This dynamic-based design, on one hand, simplifies the reaction mechanism to make purification easier, and on the other hand, the concentrated release of entropy during the reaction process promotes phase transition and related element homogenization.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·Vol. 46
·期 2
·117844
·
IF 6.2
Zhuangzhuang Ma,Yunhao Wang,Tianhao Rui,Yulin Lan,Linyuan Lu,Yang Yu,Mingxuan Deng,Tianxing Lan,Zhekang Zhao,Zhen Teng,Haibin Zhang
High-entropy pyrochlore ceramics with the nominal composition Eu 2 B 2 O 7 , incorporating up to five equiatomic B-site cations, were synthesized via a solid-state reaction method and evaluated their aqueous chemical durability for nuclear waste immobilization. Comprehensive characterization using XRD, Raman, and SEM analyses confirmed the formation of a single-phase pyrochlore structure with uniform and random elemental distribution. However, secondary phases were observed in the Ce- and Nb-doped samples, which is attributed to the larger ionic radius of Ce and the higher valence state of Nb. The 42 days leaching tests revealed normalized element release rates ranging from 10 −5 to 10 −7 g/(m 2 ∙d), significantly lower than those of conventional pyrochlore materials. This enhanced durability is attributed to synergistic effects of electronegativity, ionic radius, and atomic number, which together hinder cation diffusion and strengthen chemical durability at the B site. These findings demonstrate the potential of Eu 2 B 2 O 7 high-entropy pyrochlore ceramics as long-term host materials for high-level radioactive waste. This study provides a valuable resource for enriching the thermophysical properties database of B-site high-entropy pyrochlore solidification, thereby supporting their engineering development.
研究领域:
材料科学
·
核化学
·
无机非金属材料
·
放射性废物处理
·
固体化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·
IF 6.2
Feihong Li,Lei Zheng,Zhanjun Liu,Mingyu Zhang,Qizhong Huang
This work delves into the fascinating transformation from organic precursors to dense SiC-modified (Ti, Zr, Hf)C solid solution ceramics. Nanocrystalline powder was crafted through an innovative sol-gel process coupled with carbothermal reduction, followed by spark plasma sintering (SPS) to obtain the multi-phase ceramics. The results indicate that the addition of silicone alkoxide is required for forming a robust multi-phase gel network, which facilitates the formation of oxide intermediates (e.g., ZrSiO 4 , HfSiO 4 ), accelerates phase transformation, and inhibits grain from coarsening by encapsulating Ti/Zr/Hf compounds while reinforcing grain boundaries. After pyrolysis at 1400 °C, the precursors gradually evolved into a highly crystalline, medium-entropy solid solution. The optimal sintered composite achieves a relative density of 97.8 % and an open porosity of 0.4 %. The mechanical properties were improved by induced lattice distortion and effect of fine-grained strengthening with the incorporation of SiC. Nanoindentation tests reveal that the hardness and elastic modulus of the (Ti, Zr, Hf)C-SiC composite reach 22.39 GPa and 342.78 GPa, respectively.
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2024
·
IF 5.7
Zaiyong Zhang,Jinglong Li,Chunlin Chen,Yuwei Tong,Dehui Liu,Cuizhi Li,Huan Lu,Li Huang,Wanling Feng,Xiaoting Sun
Brain natriuretic peptide (BNP) is considered to be an important biomarker of heart failure (HF) attracting attention. However, its low concentration and short half-life in blood lead to a low-sensitivity detection of BNP, which is a challenge that has to be overcome. In this work, we propose a highly specific, highly sensitive T7 RNA polymerase-assisted clustered regularly interspaced short palindromic repeats (CRISPR)/Cas13a system to detect BNP via an electrochemiluminescence (ECL) sensing platform and incorporate Exo III-hairpin and dumbbell-shaped hybridization chain reaction (HCR) technologies. In this detection scheme, the ECL sensing platform possesses low background signal and high sensitivity. Firstly, the T7 promoter-initiated T7 RNA polymerase acts as a signal amplification technique to generate large amounts of RNAs that can activate CRISPR/Cas13a activity. Secondly, CRISPR/Cas13a is able to trans -cleave the surrounding trigger strand to produce DNA1. Thirdly, DNA1 is involved in the co-amplification reaction of Exo III and hairpin DNA, which subsequently triggers a dumbbell-shaped HCR technology. Eventually, a large number of Ru (II) molecules are inserted into the interstitial space of the dumbbell-shaped HCR to generate a strong ECL signal. The CRISPR/Cas13a possesses outstanding specificity for a single base and increased sensitivity. The tightly conformed dumbbell-shaped HCR provides higher sensitivity than the traditional linear HCR amplification technique. Ultimately, the clever combination of several amplification reactions enables the limit of detection (LOD) as low as 3.2 fg/mL. It showed promise for clinical sample testing, with recovery rates ranging from 98.4% to 103% in 5% human serum samples. This detection method offered a valuable tool for early HF detection, emphasizing the synergy of amplification strategies and specificity conferred by CRISPR/Cas13a technology.
研究领域:
生物技术
·
分子生物学
·
分析化学
·
临床诊断
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）