JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·
IF 6.2
Weijia Guo,Yutian Lu,Chongyang Zhang,Zhenxing Yue
Low-loss (high- Q × f , where Q = 1/tan δ ) dielectric ceramics can help achieve efficient microwave signal transmission and reduce heat generation. In the traditional Ca-Ln-Ti-O perovskite system (where Ln = rare earth) with the general formula of Ca 1– x Ln 2 x /3 TiO 3 (CST x ), the sharp decline in the Q × f value when x > 0.5 remains unexplained, posing a challenge for designing low-loss ceramics. In this study, CST x ceramics ( x ≤ 0.7) are synthesized via the solid-state reaction method, with a focus on their structure, defects, and broadband dielectric properties. A significant discrepancy between the Q × f values in the microwave and terahertz bands is found when x ≥ 0.6, suggesting the presence of additional loss mechanisms in the microwave band beyond ion displacement depolarization. Meanwhile, the low-frequency dielectric spectra show a weak dielectric relaxation in the low-temperature region, attributed to the partially ordered A -site vacancies. Therefore, this relaxation can act on the microwave frequency band at room temperature, resulting in a sharp decline in Q × f values. Such low-frequency and low-temperature dielectric relaxation should not be ignored in the research of microwave dielectric ceramics. These findings provide a crucial theoretical reference for developing low-loss microwave dielectric ceramics.
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
FUEL
·
2022
·
IF 8.035
Mingjia Zhang,Shule Zhang,Fanyu Meng,Mengjie Hu,Zhongyu Wang,Yiqing Zeng,Qin Zhong
Promoting the formation of Ti-OOH in the TiO 2 -based-catalyst/H 2 O 2 /O 3 system is critical to further develop the catalytic peroxone process for low-temperature flue gas denitration. In this study, a series of phosphorus-doped TiO 2 with rich Lewis acid sites and high stability was designed and established, achieving 94 % NO oxidation efficiency with less oxidant (373 K, H 2 O 2 /NO = 1.2, O 3 /NO = 0.5) and high GHSV (1.2 × 10 5 h −1 ). Combining characterizations and DFT results, a possible mechanism was proposed: phosphorus-doping enhanced the Lewis acidity, which was conducive to the adsorption and activation of H 2 O 2 . Moreover, P-TiO 2 significantly promoted the H 2 O dissociation and Ti-OOH formation process by reducing the energy barrier, thereby promoting the synergistic effect between O 3 and Ti-OOH. The semi-in-situ UV–vis DRS demonstrated that the catalytic peroxone process occurs at the solid–liquid interface and the Ti-OOH is consumed in the catalytic process. We hope this work provide a new investigation method and insight into the catalyst design.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Materials Research Express
·
2021
·Vol. 8
·期 12
·125006
·
IF 1.62
Peng She,Chun Yao,Jun Li,Hegang Bao,Xiuquan Xu,Hong Zhou
Co-doping is one of the most facile and efficient strategies for boosting the photocatalytic performance of g-C3N4. Herein, a series of Ti and O co-doped g-C3N4 (Ti/OCN) composites with excellent photocatalytic inactivation activity of Enterobacter cloacae (E. cloacae) were successfully synthesized by simple calcination of urea/formic acid/TiCl4 precursor. The obtained Ti/OCN-3 possessed the optimal photocatalytic capability with complete inactivation of 6.20 log CFU·ml−1 E. cloacae under 60 min of visible light irradiation. The improved photocatalytic disinfection performance was probably attributed to the synergistic effect of Ti and O co-doping, which led to an extended visible light response and accelerated charge transport efficiency. Furthermore, scavenger trapping and electron spin resonance (ESR) experiments revealed that ·O2−, h+ and ·OH were responsible for the enhanced inactivation activity. Overall, this research provided a promising strategy for fabricating g-C3N4-based catalysts to efficiently deal with the hazards of pathogenic microorganisms.
研究领域:
环境科学
·
微生物学
·
材料科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Bingbing Cui,Guodong Fu
Given that heterojunction engineering is an effective method for improving the separation efficiency of photoexcited electrons in WO 3 -based photochromic systems, a series of solid-state photochromic Zr/Ti-MOF@WO 3 heterojunctions prepared via a facile hydrothermal strategy, where Zr/Ti-MOF with photosensitivity and chemical stability was selected as template to load WO 3 . Zr/Ti-MOF@WO 3 heterojunctions were verified as nanoparticles filled with thin layer structure and WO 3 was diffused into the Zr/Ti-MOF planar. The appropriate conductive band energies facilitate the transport of photostimulated electrons from Zr/Ti-MOF to WO 3 , resulting in a fast photresponse in color changes (it only takes 1 s). In addition, a carrier for information storage and data dynamic encryption was developed on the basis of the photochromic Zr/Ti-MOF@WO 3 heterojunctions. This work presents a promising way to improve the electron/holes separation efficiency by constructing unique heterojunctions and further explore novel WO 3 -based photochromic systems and broaden their applications in rewritable media and data security.
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
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 35
·12244-12252
·
IF 4
Shen Yu,Zhan Liu,Jia-Min Lyu,Chun-Mu Guo,Yi-Long Wang,Zhi-Yi Hu,Yu Li,Ming-Hui Sun,Li-Hua Chen,Bao-Lian Su
The catalytic oxidative desulfurization (ODS) technique is able to remove sulfur compounds from fuels, conducive to achieving deep desulfurization for the good of the ecological environment. Ti-based metal–organic frameworks (Ti-MOFs) possessing good affinity to organic reactants and considerable numbers of Ti active sites are promising catalysts for ODS. However, current Ti-MOFs suffer from severe diffusion limitations caused by the size mismatch between sole micropores and bulky sulfur compounds, leading to poor ODS performance. Here, a facile method of intraparticle ripening without any additive is developed to obtain hierarchically meso–microporous Ti-MIL-125 single crystals (Meso-Ti-MIL-125) for the first time. Such Meso-Ti-MIL-125 shows a BET surface area of 1401 m2 g−1 and a mesoporous volume that is 1.7 times as high as that of the conventional Ti-MIL-125. Our novel Meso-Ti-MIL-125 exhibits excellent catalytic performance in the ODS of a series of bulky thiophenic sulfur compounds, completely removing benzothiophene (BT), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (DMDBT) from model fuels, which is, respectively, 2.4 times, 1.5 times, and 6.7 times higher than the removal achieved with conventional Ti-MIL-125. Such a facile synthetic strategy is envisioned to be applied in many kinds of crystalline materials, such as zeolites, for industrial production.
研究领域:
化学工程
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材料科学
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环境科学
·
催化
✓ 已验证
DOI
PubMed
高影响因子
Biomaterials Science
·
2013
·Vol. 1
·期 7
·703-710
·
IF 0
Chaoyong Zhao,Hongfang Zhang,Bing Cai,Guanglin Wang,Hongsong Fan,Xingdong Zhang
In this study, a porous PLGA/Ti biphasic scaffold was prepared and its potential to repair osteochondral defects was evaluated. The microstructure and mechanical properties of porous PLGA and porous Ti and their interface were characterized. The as-prepared biphasic scaffolds were implanted into rabbit knees for 1 and 3 months (PLGA/Ti group), and the porous PLGA (PLGA group) or empty defect (Untreated group) was also used. The results showed that both porous PLGA and porous Ti had an interconnected porous structure. The mechanical strength of porous PLGA and porous Ti was similar to that of cartilage and subchondral bone, respectively. The interface analysis revealed that the as-prepared biphasic scaffold had good overall integrity and interface stability. The gross observation and histological evaluation of specimens showed that hyaline-like cartilage filled the defects to a certain extent at 3 months for both PLGA/Ti and PLGA groups while the defects remained in an untreated group. In the PLGA/Ti group, better cartilage and subchondral bone repair was observed, and quantitative macroscopic and histological score evaluations confirmed this result, indicating that the porous biphasic PLGA/Ti scaffold had good biocompatibility and the best osteochondral defect repair ability in this study. The as-prepared porous biphasic scaffold showed the potential to be used in osteochondral tissue engineering for osteochondral defect repair.
研究领域:
组织工程
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骨科
·
生物材料
✓ 已验证
产品关联
DOI
PubMed
Materials Today Communications
·
2024
·
IF 3.7
Xinbo Zhao,Zan Li,Yuye Dou,Xiaohui Jiang,Fan Bu,Zhenxia Liu,Liangmin Yu
Antibiotic wastewater poses a significant threat to the global environment and human health. In this work, Ni-Ti bimetallic Metal-Organic Frameworks (NT-MOF) were synthesized as effective photocatalysts to remove tetracycline (TC) from water under visible light irradiation. The photocatalysts underwent characterization using techniques such as Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), N 2 adsorption-desorption, and X-Ray Photoelectron Spectroscopy (XPS). Photocatalytic tests were conducted under visible light conditions (λ>420 nm). The enhanced performance is mainly due to the presence of Ni in NT-MOF changing the shape and structure of the samples, reducing electron-hole recombination, thus promoting the charge separation process. These findings have significant implications for the development of efficient and sustainable methods for the removal of TC from wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscience and Nanotechnology Letters
·
2017
·Vol. 9
·期 9
·1356-1362
·
IF 1.889
Xu Jianxiong,Xie Shaowen,Feng Yahui,Du Jingjing,Xu Lijian
TiO2 nanoparticles with average diameter of 510 nm were prepared by sol–gel surfactants, and the hierarchically nanoporous Ti–SiO2 particles were further prepared using in-situ method. The hierarchically nanoporous Ti–SiO2 particles
with hollow structure were analyzed by transmission electron microscope (TEM), energy dispersive spectrometer (EDS), scanning electron microscope (SEM), nitrogen adsorption stripping curves and Barrett-Joyner-Halenda (BJH) pore size distribution curves. Finally, the hierarchically nanoporous
Ni–Mo composite electrodes were prepared using the TiO2 nanoparticles or nanoporous Ti–SiO2 particles as composite particles respectively, and the influence of the concentration of composite particles on the electrocatalytic activities of Ni–Mo composite
electrodes for hydrogen evolution were investigated by polarization curves. The results showed that the diameter of Ti–SiO2 particles was from 200 nm to 500 nm, and specific surface area was 573 m2/g with pore volume of 1.19 cm3/g and mesopore size of
3.2 nm. The TiO2/Ni–Mo and Ti–SiO2/Ni–Mo composite electrodes were fabricated by electrodeposition with TiO2 nanoparticles and nanoporous Ti–SiO2 particles as composite particles respectively. The electrocatalytic activities
of TiO2/Ni–Mo and Ti–SiO2/Ni–Mo composite electrodes for hydrogen evolution were investigated. Results showed that the electrocatalytic activities of TiO2/Ni–Mo and Ti–SiO2/Ni–Mo composite electrodes for hydrogen
evolution reached the optimal value when the concentration of particles was 4 g/L and 2 g/L respectively. The electrocatalytic activities of TiO2/Ni–Mo and Ti–SiO2/Ni–Mo composite electrodes were greater than that of Ni–Mo alloy electrode, and
the Ti–SiO2/Ni–Mo composite electrode showed the best electrocatalytic activity.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Wei Song,Hanqing Zhao,Jianqi Ye,Mengmeng Kang,Siyu Miao,Zhong Li
Ti–O–C channels for ultrafast sodium storage were constructed in N/S-co-doped TiO2–C nanofibers, which deliver a high rate performance of 181.9 mAh g–1 at 5 A g–1 after 3000 cycles. The existence of Ti–O–C bonds at the interface of TiO2–C phases was revealed by synchrotron radiation X-ray absorption spectra. Based on this, first-principles calculations further verified the low energy barrier for Na+ insertion/extraction in the Ti–O–C channels formed by the intimately integrated graphite layer with TiO2 near the surface. In addition, surface defects induced by heteroatoms accelerate the Na+ mass transfer through the pathway from the carbon surface to the Ti–O–C channel.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 8
·5142-5148
·
IF 3.9
Chunhong Jin,Jingchao Liu,Yilin Yin,Zenghe Li
In wastewater containing heavy metals, Cr(VI) is a potentially toxic metal, mainly derived from production and processing processes such as textile printing, dyeing, ore mining, battery applications, metal cleaning and electroplating. WO3 is widely used in photocatalytic degradation and reduction, and its utilization rate of visible light is high. However, the rapid recombination of photogenerated electron–hole pairs of WO3 limits its use. In this work, the composite material (WxMy) of WO3 and MIL-125 (Ti) was prepared by the ball milling method, and the catalyst was used to photocatalytically reduce Cr(VI). After using W90M10 as a photocatalyst for 50 min, the reduction rate of Cr(VI) can reach 99.2%, and the reduction rate is 2.3 times that of WO3. After 5 cycles of use, the reduction rate can still reach 91.3%. It is mainly due to the formation of a II-type heterojunction between WO3 and MIL-125 (Ti), which promotes the separation of photogenerated electron–hole pairs, thus improving the efficiency of photocatalytic reduction of Cr(VI).
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2012
·
IF 2.103
Zhen Wang,Xinbo Ci,Hongjun Dai,Lu Yin,Huixiang Shi
A highly photoactive Ti-containing Cr-modified MCM-48 photocatalyst (Si/Ti = 3.4, Si/Cr = 50) was prepared by a facile one-step method at room temperature. A combination of various physicochemical techniques such as X-ray diffraction (XRD), N 2 physisorption, diffuse reflectance UV–vis spectra (DRS) and X-ray photoelectron spectra (XPS) were used to characterize the properties of the synthetic catalysts. The characterization and experimental results indicated that tetrahedral Ti oxide moieties as dominant Ti oxide were loaded into the mesoporous structure and there was a synergistic interaction between the Ti species anchored on the walls and the Cr ions presented in the MCM-48 framework, which was considered to be directly correlated to the photoactivity. The Ti-Cr-MCM-48 sample can remove H 2 S with the efficiency of 92% under visible light, being the Cr 6+ species primarily responsible for this photoactivity. A deactivation was observed as a consequence of sulfate accumulation on the surface of the catalyst and reduction of Cr 6+ .
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Mazhar Khan,Zeeshan Akmal,Muhammad Tayyab,Seemal Mansoor,Dongni Liu,Ziwei Ye,Jinlong Zhang,Shiqun Wu,Lingzhi Wang
The rational design of heterojunction photocatalysts is crucial for enhancing CO 2 photoreduction efficiency, yet precisely channeling photogenerated electrons to the CO 2 adsorption sites remains an enormous challenge. In this work, we developed an organic-inorganic heterostructure with continuous inter- and intra-component electric fields. The integration of BiOBr with MIL-125 via chemical bonding established a heterojunction, where the built-in electric field between the two components facilitated the efficient transfer of photogenerated electrons from BiOBr to MIL-125. The intrinsic electric field of MIL-125 further drove the accumulation of photogenerated electrons at Ti sites. This tandem electric field effect, in conjunction with the CO 2 adsorption and activation at Ti sites, significantly enhanced the efficiency of CO 2 reduction within the heterojunction system. The optimized photocatalyst achieving CO production at a rate of 65.6 μmol g −1 h −1 with nearly 90 % selectivity without the use of sacrificial agents, exhibiting a remarkable 43-fold and 8-fold enhancement in activity compared to pristine MIL-125 and BiOBr, respectively. In-situ infrared spectroscopy and theoretical calculations confirmed the energy optimization effect of the heterostructure on CO 2 activation and the hydrogenation reaction, facilitating the formation of the key intermediate *COOH. This work elucidates the mechanism by which tandem built-in electric fields facilitate charge separation.
研究领域:
材料科学
·
环境科学
·
催化化学
✓ 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）