ACS Applied Electronic Materials
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2023
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IF 4.7
Xueqi Yin,Guoke Wei,Aijun Gong,Xianglin Zhou
This paper focuses on the effect of the porosity of Fe3O4 on electromagnetic wave (EMW) loss. The pore structures were based on the Voronoi method by MATLAB, and the electromagnetic fields were constructed based on COMSOL Multiphysics. The energy loss of EMWs with frequencies of 2–18 GHz through Fe3O4 nanoparticles with different porosities was simulated and analyzed. Well-defined porous Fe3O4 nanostructures were synthesized by heating FeCl3·6H2O, urea, and surfactant (TBAB) in an ethylene glycol solution. Then, the prepared samples were eroded with oxalic acid to obtain different porosities. The electromagnetic parameters of the experimental samples were tested to validate the simulation results. The results showed that increasing the porosity, to some extent, was beneficial to the impedance matching characteristics, thus improving the EMW loss. The simulation results with different porosities and the experimental results with varying pore volumes had some consistency. When the porosity of the digital model was 30.63% and the pore volume of the experimental samples was 0.3102 cm3/g, |Zin/Z0| was the closest to 1, indicating that the impedance matching was the best. At the same time, it was found that the pore volume of the material can be used to characterize the porosity during the experimental preparation, thus simplifying the data processing.
研究领域:
材料科学
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电磁学
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纳米技术
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模拟与建模
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产品关联
DOI
高影响因子
WASTE MANAGEMENT
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2022
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IF 8.816
Yan Li,Guangyu Chen,Wenxin Liu,Chentong zhang,Liuqing Huang,Xuetao Luo
Owing to the rapid advancement of the photovoltaic industry, a lot of photovoltaic (PV) silicon waste will be generated. Thus, the recycling and reuse of waste silicon have become particularly important, both for environmental remediation and economic benefits. In this work, a special structure of porous Si nanoparticles embedded nano-Ag and coated carbon layer (P-SiNPs/Ag@C) was produced by silver-assisted chemical etching (Ag-ACE) the deposited silicon waste. The special porous structure and carbon layer coating can effectively address the volume expansion issues during charge/discharge. The intercalated Ag nanoparticles greatly reduced the transfer impedance and enhanced the electrical conductivity of the anode material. As a result, the novel-designed P-SiNPs/Ag@C anode can maintain a prominent reversible capacity (1521 mAh·g −1 at 0.2 A g −1 after 50 cycles) and outstanding rate performance (1099 mAh·g −1 at 2 A g −1 ). When the current density at 1 A g −1 , the specific capacity still maintains at 706 mAh·g −1 over 300 cycles. The superiority of the prepared P-SiNPs/Ag@C structures was further confirmed by Comsol Multiphysics software. Impressively, the synthesis route provides a novel avenue for value-added utilization of residual silicon waste resources from EB refining silicon and the preparation of high-performance lithium battery silicon-based anode.
研究领域:
材料科学
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能源存储
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环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2023
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IF 9.5
Xiaoguang Zhao,Yili Tang,Jie Wang,Yihang Li,Daokui Li,Xiaochao Zuo,Huaming Yang
Fully stimulating the capacity of light-driven phase change materials (PCMs) for efficient capture, conversion, and storage solar energy requires an ingenious combination of PCMs, supporting structural materials, and photothermal materials, therefore motivating the synergistic effects between the components. Herein, this work thoroughly explores the interaction forces between PCMs and supporting structural materials and the synergy between PCMs and photothermal materials in photothermal conversion. Rejoicingly, when capitalizing on the prepared directional channel structure of hierarchically porous composite aerogel (PEPG) as a supporting structural material, a superior paraffin wax (PW) encapsulation rate of 85.11% is achieved, and the prepared PEPG2-PW has a high phase change enthalpy of 182.9 J/g. The van der Waals force and Lewis acid-base action between PEPG and PW molecules reveal the excellent stabilities of PEPG-PW. More importantly, the PEPG2-PW has an ultrahigh photothermal conversion efficiency of 95.2% under 1 sun irradiation and durability. Most importantly, the COMSOL Multiphysics software calculations demonstrate that transparent PW can anchor sunlight on the surface of graphite nanoplates, converting it into heat by enhancing the loss of graphite backbone lattice vibrations, and the accumulated heat is then stored in molten PW. This work provides some design principles for high-efficiency solar-thermal conversion materials.
研究领域:
材料科学
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能源存储
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光热工程
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纳米技术
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复合材料
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产品关联
DOI
PubMed
高影响因子
ULTRASONICS SONOCHEMISTRY
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2025
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IF 9.7
Longshi Rao,Shengxin Zhu,Jiaying Liu,Qiuling Bai,Junxian Zou,Chuheng Deng,Hongze Tu,Qingxian Liu,Guisheng Zhong,Xiaodong Niu,Jiasheng Li
Carbon dots (CDs) are promising fluorescent nanomaterials with broad applications in optoelectronics, healthcare, and artificial photosynthesis. However, synthesizing indigo-emitting CDs with optimal properties remains challenging due to the inefficiencies and complexity of conventional methods. This study introduces a high-performance ultrasonic microreactor inspired by biomimetic leaf vein structures to enhance CD synthesis efficiency. We developed a COMSOL Multiphysics-based optimization framework to improve flow field uniformity and examine transport dynamics within the microchannel. This framework identified key parameters, including leaf vein contours, fractal angles, depth-to-width ratios, and inlet configurations, that govern flow characteristics. Additionally, we optimized ultrasonic energy transfer by directly coupling the transducer with the microreactor, determining the optimal frequency (21 kHz) and power (100 W) for maximum reactor performance. Visualization experiments revealed how ultrasound regulates bubble dynamics, enhancing interfacial area and stabilizing suspension behavior. Using this optimized system, we synthesized indigo-emitting CDs with a maximum PLQY of 27.5 % and a narrow FWHM of ∼78 nm under 365 nm excitation. Multivariate experiments revealed how flow velocity, reaction temperature, and ultrasonic modulation influence the optical properties of the CDs. This work underscores the synergistic combination of ultrasonic energy, biomimetic design, and simulation-guided optimization, providing a solid foundation for scalable synthesis of carbon-based nanomaterials with applications in optoelectronics, healthcare, and beyond.
研究领域:
纳米技术
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材料科学
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化学工程
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光电子学
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声学工程
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仿生学
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产品关联
DOI
PubMed
高影响因子
CHEMISTRY OF MATERIALS
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2021
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IF 9.811
Chi Chen,Yangyuanchen Liu,Ximin He,Hua Li,Yujie Chen,Ying Wei,Yusen Zhao,Yanfei Ma,Zhen Chen,Xu Zheng,Hezhou Liu
In the field of bionic soft robots and microrobots, artificial muscle materials have exhibited unique potential for cutting-edge applications. However, current mainstream thermal-responsive artificial muscles based on semicrystalline polymers (SCPs), despite their excellent physical properties, suffer from the limitation of environmental stimuli in practice, while their photodriven counterparts adopting liquid crystal elastomers (LCEs) lack ductility. Herein, a novel multifunctional programmable artificial muscle with a unique patch-sewing structure formed by π–π stacking between azobenzene groups was designed, which combined the advantages of SCPs and LCEs. The nanocomposite demonstrated a unique combination between artificial muscle performance (46.5 times the energy density and 26.6 times the power density of human skeletal muscles) and programmability (274.84% strain and 100% shape-memory recovery rate within 1 s). Meanwhile, coupling the photoisomerization of azobenzene and the photothermal conversion of gold nanorods, the cycle of deformation triggered by ultraviolet light and restoring by infrared light could be accomplished rapidly within 30 s. A COMSOL Multiphysics model was established and the corresponding finite element analysis verified the photoactuation and captured the general principle of light initiation in elastomers. These demonstrate that the multifunctional programmable elastomer is promising for artificial muscle applications, especially for photoinduced actuation.
研究领域:
仿生学
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软体机器人
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微机器人
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材料科学
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纳米技术
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光响应材料
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2023
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IF 5.7
Weijia Guo,Zhiyu Ma,Yutian Lu,Zhenxing Yue
High- Q and temperature-stable ceramics are indispensable in microwave engineering. However, medium-permittivity ( ε r ∼ 60, named as K60) microwave dielectric ceramics that meet the above demands are yet to be synthesized. High- Q Ba 4 Sm 9.33 Ti 16.5 Al 2 O 54 (BSTA) and Ca 0.6 Sm 0.27 Ti 0.8 Al 0.27 O 3 (CSTA) ceramics have large resonant frequency temperature coefficients ( τ f ) with opposite signs. The composites of the two are expected to have good dielectric properties , but there will be obvious diffusion when they are compounded with each other by sintering after directly mixing the raw powder, which would lead to severe deterioration in dielectric properties. In this work, the undesired diffusion can be effectively avoided by stacking two or three ceramic layers together, which are achieved by two methods named adhesive bonding and spark-plasma-sintering (SPS) cofiring. The finite element method (FEM) analysis with COMSOL Multiphysics proposed in this work can precisely predict the microwave dielectric properties of layered ceramics, helping to determine the ratio of different layers to reach near-zero τ f . The adhesive-bonded layered ceramics exhibit excellent dielectric properties: ε r = 62.2, Q × f = 21,400 GHz, and τ f = –0.7 ppm/°C. The SPS-cofired layered ceramics can be fabricated in one time, partially solving the problem of sintering mismatch between different layers, together with superior properties of ε r = 59.8, Q × f = 19,780 GHz, and τ f = –0.6 ppm/°C. These layered ceramics could fill the gap of high- Q and temperature-stable K60 microwave dielectric ceramics. The layer-stacking process and related FEM simulations can be used to design more high- Q and temperature-stable microwave dielectric ceramics and devices.
研究领域:
材料科学
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陶瓷
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微波工程
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介电材料
✓ 已验证
DOI
高影响因子
DRYING TECHNOLOGY
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2023
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IF 3.3
Wei Wang,Shuo Zhang,Yanqiu Pan,Yijia Ji,Xin Li,Guohua Chen,Xuewu Liu
A multiphase transport model was formulated to explore the adaptability of local thermal and mass equilibrium/non-equilibrium (LTE/LTNE and LME/LMNE) assumptions in simulating freeze-drying of porous media. Saturated and unsaturated samples with the same initial mass and moisture content but different initial saturations were used in freeze-drying experiments and numerical simulations. Four pairwise combinations between LTE/LTNE and LME/LMNE were tested using the commercial software of COMSOL Multiphysics based on the finite element method. Results showed that the LTE-LMNE assumption achieved excellent agreements between numerical and experimental drying curves with RMSEs being 1.81% for the saturated sample and all less than 1.00% for the unsaturated samples. Based on distributions of saturation and temperature, and variations of effective mass diffusivity and thermal conductivity, the rate-controlling factor was determined to be mass transfer for the saturated material and heat transfer for the unsaturated one. Convective heat transfer played an unimportant role in freeze-drying. The LTE-LMNE based model provided satisfactory predictive capabilities under different conditions. Appropriately increasing the operating temperature could boost the drying rate. Changing the chamber pressure had insignificant effects with drying time differences only below 3%. The smaller the initial saturation, the shorter the drying time. The initially unsaturated frozen material with preformed pores significantly enhanced the freeze-drying process and improved the process economy.
研究领域:
化学工程
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热能工程
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材料科学
✓ 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）