JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2025
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IF 3.8
Yiran Liu,Yimin Ouyang,Linwei Guo,Saidi Wang,Yihui Yang,Bin Du,Tao Zhang
Polymer-derived SiOC ceramics have demonstrated significant potential across various applications, including structure materials, energy, extreme thermal environments, and semiconductors. It is well-established that the carbon phase in SiOC plays a crucial role in determining the material's properties. However, the relationship between carbon phases and the mechanical properties of SiOC ceramics remains inadequately explored. In this study, a series of SiOC nanosphere powders with varying carbon content were successfully fabricated, and bulk samples were obtained using the spark plasma sintering (SPS) technique. The results demonstrate that both carbon content and sintering temperature play a synergistic role in determining the phase composition—such as the formation of SiC through carbothermal reduction—and the microstructural features, including densification and the distribution of free carbon in SiOC ceramics. These structural modifications significantly enhance the mechanical properties through multiple mechanisms. Among all the samples, the SiOC-C ceramics fabricated at 1600°C possess optimized mechanical properties, with a flexural strength of 38.48 MPa. These findings elucidate the potential mechanism for improving the mechanical properties of SiOC ceramics by introducing the carbon phase, which holds significant implications for the development of high-performance ceramic materials.
研究领域:
材料科学
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机械工程
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DOI
高影响因子
Agronomy-Basel
·
2022
·Vol. 12
·期 2
·476
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IF 3.949
Gang Chu,Zifeng Han,Zimo Wang,Defeng Kong,Wenxiu Qin,Youbin Si,Guozhong Wang,Christian E. W. Steinberg
Massive biomass waste with lignocellulose components can be used to produce biochar for environmental remediation. However, the impact of lignocellulose pyrolysis on biochar structure in relation to the sorption mechanism of ionizable antibiotics is still poorly understood. In this paper, diverse techniques including thermogravimetric analysis and13C nuclear magnetic resonance were applied to investigate the properties of biochars as affected by the pyrolysis of cellulose and lignin in feedstock. Cellulose-derived biochars possessed more abundant groups than lignin-derived biochars, suggesting the greater preservation of group for cellulose during the carbonization. Higher sorption of sulfamethoxazole (SMX) was also observed by cellulose-derived biochars owing to hydrogen bond interaction. Sorption affinity gradually declined with the conversion aliphatic to aromatic carbon, whereas the enhanced specific surface area (SSA) subsequently promoted SMX sorption as evidenced by increased SSA-N2and SSA-CO2from 350 to 450 °C. The decreasedKd/SSA-N2values with increasing pH values implied a distinct reduction in sorption per unit area, which could be attributed to enhanced electrostatic repulsion. This work elucidated the role of carbon phases from thermal conversion of lignocellulose on the sorption performance for sulfonamide antibiotics, which will be helpful to the structural design of carbonaceous adsorbents for the removal of ionizable antibiotics.Keywords:biochar;lignocellulose pyrolysis;carbon phase;ionizable antibiotics;sorption mechanism
研究领域:
环境科学
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材料科学
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DOI
高影响因子
ACS Catalysis
·
2024
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IF 11.3
Yiwei Sun,Xiaoli Wei,Wei Zhang,Zhen Wang,Jianhai Jiang,Fangcao Liu,Bing Liu,Wenfeng Han
Conversion of potent greenhouse gases, hydrofluorocarbons (HFCs), to value-added hydrofluoroolefins (HFOs) is of great importance. AlF3 catalysts play a major role in this process. Formation and maintenance under coordinated Al are the key to prepare efficient catalysts. Herein, carbon interacted AlF3 nanoclusters catalyst (AlF3–SAPO-5) was effectively achieved with SAPO-5 molecular sieves as precursors via pyrolysis followed by in situ fluorination. This process results in a strong interaction between the carbonaceous material and active aluminum (Al) species. The results show that AlF3–SAPO-5 possesses both high activity and thermal stability. For 1,1-difluoroethane (HFC-152a) dehydrofluorination, the conversion can reach up to 95% at a reaction temperature of 350 °C. The reaction rate is almost 4 times higher than that of AlF3 prepared by traditional pyrolysis (AlF3-py). It implies that the confinement effect contributes to the formation of AlF3 nanoclusters with abundant 4- and 5-coordinated Al species stabilized by the F–Al–O–C structure. In addition, the carbon-interacted AlF3 nanoclusters exhibit superb sintering resistance. Given its fantastic activity and thermal stability, the carbon-interacted AlF3 nanoclusters show great potential for the catalytic dehydrofluorination of fluorinated alkanes.
研究领域:
化学工程
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材料科学
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催化反应
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DOI
高影响因子
COMPOSITES PART B-ENGINEERING
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2019
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IF 6.864
Shanshan Xiao,Hui Mei,Daoyang Han,Laifei Cheng
SiC nw /C/Si 3 N 4 porous ceramic composites with layer-by-layer structure were successfully fabricated by freeze drying, carbonization and chemical vapor infiltration processes for excellent room and high temperature electromagnetic (EM) wave absorption properties . The sandwich-like structure within the layer and the capacitor model structure between the layers are formed inside of the composite, and these structures are beneficial to the EM wave consumption. The EM absorption properties are optimized by regulating the relative contribution of the polarization loss (primarily provide by SiC nw and defects in carbon phase) and the conductance loss (primarily offered by the conductive network formed by the carbon thin film). As an antioxidant protective layer, Si 3 N 4 ceramic coating is prepared on the outside of the carbon film . The prepared SiC nw /C/Si 3 N 4 porous composites show high absorption efficiency (exceed −39.7 dB), wide absorption band (cover the whole X band), small density (0.92 g/cm 3 ), thin thickness (2.9 mm), and excellent high-temperature stability (stable up to 873 K). The unique structures not only facilitate EM wave absorption, but also enable the composite a compressive strength of 168 MPa.
研究领域:
材料科学
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电磁学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Wenli Wang,Guangxing Yang,Qiang Wang,Yonghai Cao,Hongjuan Wang,Hao Yu
Heteroatom doped carbon materials have been synthesized and served as catalyst supports for Pd nanoparticles (NPs). Numerous Pd-carbon catalysts can be produced via single-, dual-, and multi-doping heteroatoms into carbon supports. Therefore, it is highly desired to seek a universal descriptor, regardless of the doping types, in guiding to the design of efficient catalysts. The electronic state of Pd affected by carbon supports is crucial in catalysis, which can be described by the binding energy (BE) accurately and conveniently using X-ray photon spectroscopy. In this work, the single (dual)-doped carbon nanotubes (CNTs) with tunable doping degrees were synthesized via thermal pyrolysis of heteroatom-containing precursors, accompanied by the defluorination of fluorinated CNTs. Density functional theory results show that the charge distributions of the doped-CNTs are determined by the doping configurations. After loading Pd NPs, the charge of the support redistributes. Meanwhile, the BEs of Pd 0 3d5/2 change correspondingly due to the electronic metal–carbon interaction (EMCI). Eventually, Pd NPs with different electronic states show the difference in the turnover frequency of phenol hydrogenation. Therefore, the electronic state of Pd NPs can be considered as a proper descriptor for estimating the catalytic performance and indicator for developing highly efficient catalysts.
研究领域:
催化材料
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化学工程
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Ping-an Yang,Wenjiao Deng,Haibo Ruan,Zhengwei Qu,Rui Li,Lirui Wang,Jiufei Luo,Zhihao Zhou,Mengjie Shou,Xin Huang,Qiao Chen,Xinglong Gong
The study of designing and developing ferromagnetic nanocomposites with both microwave absorption (MA) and corrosion protection properties through microscopic heterogeneous interfacial engineering and crystal phase engineering remains challenging. In this study, Fe@C core–shell nanowires (FCNWs) are obtained by magnetic field-controlled in situ reduction method and annealing process to de-regulate the carbon shell thickness and carbon morphology. The enhancement of Fe-C heterogeneous relative interfacial effects and dielectric/magnetic response is revealed using density functional theory and simulated electromagnetic field distribution, and the modulation of the amorphous carbon/graphitic carbon ratio achieves the enhancement of dipole polarization in the low-frequency region. The FCNWs absorber had a minimum reflection loss (RL min ) of −47.6 dB at a thickness of 4.9 mm, and the maximum effective absorption bandwidth (EAB max ) was achieved at 5.5 mm up to 4.0 GHz. In addition, the shielding effect of the graphitic carbon shell on the corrosion medium and the addition of additional electron conduction pathways allow the FCNWs absorber to obtain smaller corrosion currents and larger polarization resistances compared to Fe nanowires. Thus, modulation of atomic-scale heterogeneous interfaces and crystal phases has great potential in modulating the dielectric response.
研究领域:
材料科学
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电磁学
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防腐蚀工程
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Xianhang Jin,Jiawei Fang,Qian Ma,Rong Wang,Weidong Zhang
As China pledges that its carbon emissions will peak before 2030 and that it will be carbon neutral by 2060, the CO 2 capture technology with high efficiency and low energy-consumption was expected in industry. CO 2 phase change absorbents, CPCAs, had shown a potential to reduce energy consumption for CO 2 capture. Although a lot of CPCAs were reported in the last decade, it still suffered from the lack of theoretical guidance for development. The effect of amine structure, which mainly affects cosolvent effect of amine and salting-out effect of formed salts, on developing CPCAs by means of cosolvent effect was clarified. For cosolvent effect of amine, 12 amines with various carbon chain lengths, isomers and substituents were determined by thermodynamical method and the log P of amine were proposed to characterize the cosolvent effect. The amine with long carbon chain and steric effect showed a high ability to act as a cosolvent to enhance the solubility of 1-butanol in H 2 O. The salting-out effect of formed salts by reacting amine and CO 2 was related to p K a of amine. The absorbent comprising amine with low log P and high p K a was prefer to exhibit phase separation behavior, and benefit to develop CPCAs. Based on this guideline, all amines in this study could be developed as CPCAs by adjusting kinds of amine and diluent. Moreover, to explore the absorption-desorption performance of developed CPCAs, DEA/1-butanol/H 2 O was used as example, the volume ratio, species distributions and CO 2 cyclic capacity were measured. When the absorption temperature was 303 K and desorption temperature was 373 K, The maximum CO 2 cyclic capacity of CPCA was 2.03 mol CO 2 ·kg −1 , which was 34.4% higher than that of 30 wt% DEA/H 2 O.
研究领域:
化学工程
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环境科学
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能源技术
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DOI
高影响因子
Nano Energy
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2020
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IF 16.602
Qi Wang,Guang-Jie Xia,Zhi Liang Zhao,Yuanmin Zhu,Xiaobo Shi,Limin Huang,Yang-Gang Wang,Meng Gu
The carbon monoxide (CO) interaction effect on active Pt-based catalysts is critical because the surface reconstruction and phase separation behavior of bimetallic catalysts in a CO environment can profoundly impact the catalysts’ activity and durability. However, because direct and dynamic observation has proven elusive, the exact failure mechanisms of the nanocrystal structural modifications induced by CO are poorly understood. In this work, we probe the dynamic structural and compositional transformations of an individual PtPb@Pt nanoplates in a CO gas atmosphere via in-situ environmental transmission electron microscopy (ETEM) and confirmed with theoretical calculations. The interaction of Pt and Pb atoms with CO molecules are revealed dynamically, including the resulting breakdown of the PtPb@Pt nanoplates. The Pt atoms aggregate on surface facets of the original PtPb lattice and the Pt-CO complex mobilizes, cracking the Pt surface layers and stripping Pb atoms from the PtPb alloy core to form Pb(CO) 4 . These interactions provide direct clues for the failure analysis of the catalyst and, thus, represent a critical step towards the design of an anti-CO interaction catalyst.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2023
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IF 8.9
Tao Pei,Feng Shi,Can Liu,Yi Lu,Xu Lin,Defa Hou,Shunxiong Yang,Jirong Li,Zhifeng Zheng,Yunwu Zheng
In this study, a novel nitrogen-doped magnetic Fe–Ca codoped biochar for phenol removal was successfully fabricated via a hydrothermal and coactivation pyrolysis method. A series of adsorption process parameters (K 2 FeO 4 to CaCO 3 ratio, initial phenol concentration, pH value, adsorption time, adsorbent dosage and ion strength) and adsorption models (kinetic models, isotherms and thermodynamic models) were determined using batch experiments and various analysis techniques (XRD, BET, SEM-EDX, Raman spectroscopy , VSM, FTIR and XPS) to investigate the adsorption mechanism and metal-nitrogen-carbon interaction. The biochar with a ratio of Biochar: K 2 FeO 4 : CaCO 3 = 3:1:1 exhibited superior properties for adsorption of phenol and had a maximum adsorption capacity of 211.73 mg/g at 298 K, C 0 = 200 mg/L, pH = 6.0 and t = 480 min. These excellent adsorption properties were due to superior physicomechanical properties (a large specific surface area (610.53 m 2 /g) and pore volume (0.3950 cm 3 /g), a well-developed pore structure (hierarchical), a high graphitization degree (I D /I G = 2.02), the presence of O/N-rich functional groups and Fe-Ox,Ca-Ox, N-doping, as well as synergistic activation by K 2 FeO 4 and CaCO 3 ). The Freundlich and pseudo-second-order models effectively fit the adsorption data, indicating multilayer physicochemical adsorption. Pore filling and π-π interactions were the predominant mechanisms for phenol removal, and H-bonding interactions, Lewis-acid-base interactions, and metal complexation played an important role in enhancing phenol removal. A simple, feasible approach with application potential to organic contaminant/pollutant removal was developed in this study.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOBIOTECHNOLOGY
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2025
·Vol. 23
·期 1
·1-19
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IF 12.6
Zhang Yi,He Xiong,Mao Xiang,Yang Yukun,Li Faqi,Han Xiaofeng,Lu Hao,Tang Liang,Yang Yujun,Wang Yan,Du Yuling,Xu Wei,Wang Zhenyu
Non-invasive deep transdermal drug delivery is required for conditions such as keloids. However, the skin’s stratum corneum barrier is the primary obstacle for transdermal drug delivery methods. Most energy sources and operational controls are located externally, making it difficult to regulate the deep delivery of a drug once it has penetrated the stratum corneum barrier. Additionally, some transdermal administration methods that provide an internal energy source are frequently invasive and can cause damage. Therefore, achieving non-invasive drug delivery to the deep dermis for such conditions is challenging. Here, we propose sono-phase-change transfersomes (SPCTs) that stably encapsulate perfluoro-n-pentane within transfersomes. These SPCTs, combined with low-frequency and low-intensity ultrasound (LFLIU), are designed to create a two-stage transdermal drug delivery system that integrates passive and active penetration. In the first stage, the deformability of SPCTs enables them to stably and passively penetrate the epidermis. In the second stage, SPCTs undergo a phase change when ultrasound irradiation is applied, transforming into microbubbles. As the microbubbles penetrate deeper, they gradually expand, rupture, and release their encapsulated substances, providing supplementary energy from within to achieve active penetration. Both in vitro and in vivo experiments revealed a significant increase in the efficiency, depth, quantity, and distribution range of the contents entering the dermis. In addition, the SPCTs combined with the ultrasound group in the keloid nude mouse model exhibited the fastest keloid volume reduction, with various indicators demonstrating that its therapeutic effect was significantly better than that of the other control groups. These findings indicate that this two-stage transdermal drug delivery system can non-invasively and safely achieve deeper and higher-dose dermal administration, offering a new strategy for treating diseases such as keloid. Graphical The working principle of the two-stage transdermal drug delivery system.
研究领域:
药剂学
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生物医学工程
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皮肤药理学
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纳米医学
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转化医学
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药物递送系统
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Energy Materials
·
2022
·Vol. 12
·期 37
·2201734
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IF 29.698
Qi Li,Jun Zhang,Lixiang Zhong,Fushan Geng,Ying Tao,Chuannan Geng,Shuzhou Li,Bingwen Hu,Quan-Hong Yang
Hard carbons have been identified as competitive anodes for Li/Na/K-ion batteries but their Li/Na/K-ion storage mechanisms significantly vary in different batteries. It is fundamental to understand the basic science behind the difference. Herein, it is theoretically revealed that defects on the carbon layers generally have an influential impact on the atomic interactions including the metal–metal (M–M) and metal–carbon (M–C) interactions, thereby determining whether the stored alkali-metal atoms are in ionic or quasi-metallic states. Upon increasing the number of metal atoms on a carbon layer composed of only hexatomic rings, K tends to be stored in an ionic state similar to Li due to the dominant M–C interaction, while on a carbon layer with defects, K tends to be stored in a quasi-metallic state similar to Na due to the dominant M–M interaction. For experimental verification, a glassy carbon, the extreme form of hard carbon with dominant sp 2 hybridization and only Stone–Wales defects, is selected as a model anode, and its Li/Na/K-ion storage mechanisms are exactly consistent with the theoretical prediction. More profoundly, for the first time, the quasi-metallic K cluster information is captured by ex situ electron paramagnetic resonance.
研究领域:
材料科学
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电化学
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电池技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）