RSC Advances
·
2020
·Vol. 10
·期 15
·8709-8716
·
IF 3.119
Lin Gu,Yunyun Dong,Yan Zhang,Bo Wang,Qing Yuan,Hongmei Du,Jinsheng Zhao
In this study, a nitrogen-containing ligand supramolecule named PPYTZ was successfully synthesized using 2,6-pyridinedicarboxylic acid chloride and 3,5-diamino-1,2,4-triazole in order to carry out oxygen reduction reaction (ORR). Such a polymer provides abundant coordination sites for iron ions, and the PPYTZ–Fe/C composite catalyst was formed with the PPYTZ–Fe complex loading on the surface of Vulcan XC-72 carbon. The physical characteristics and ORR performance of the composite catalysts were characterized systematically via various relevant techniques, and their catalytic activity and reaction mechanism were evaluated and compared. The results showed that the catalytic activities and the reaction mechanism of ORR were highly dependent on the formation of an Fe–N unit. Accordingly, the PPYTZ–Fe/C catalyst containing Fe–N active sites exhibited high ORR catalytic activity (an onset potential of +0.86 V vs. RHE) in 0.1 M KOH. Such an Fe–N catalyst can accelerate the adsorption of O2 and increase the limiting current density (from 2.49 mA cm−2 to 4.98 mA cm−2), optimizing the ORR catalytic process from a two-electron process to a four-electron process (an n value of 3.8).
研究领域:
材料科学
·
电化学
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DOI
PubMed
高影响因子
NANO
·
2019
·
IF 1.293
Liuyang Heng,Zilong Zhang,Shuai Wang,Xiqiao Chen,Xiubo Jia,Zhixiang Tang,Yanhong Zou
Core–shell structured Fe/C have been successfully derived from a metal-organic framework for microwave absorbing. Based on the measured electromagnetic parameters, it is found that the maximum reflection loss (RL) of Fe/C reaches − 4 0 dB at 5.8 GHz with a thickness of 3.0 mm and the broadest absorption bandwidth ( RL < − 1 0 dB) is up to 6.0 GHz (from 11.2 to 17.2 GHz) with a thickness of 1.5 mm. The excellent microwave absorption is mainly ascribed to the multiple reflections, good impedance matching, dielectric loss and interface polarization originating from the core–shell structure. It is believed that Fe/C can be a promising microwave absorbing material.
研究领域:
材料科学
·
电磁功能材料
·
微波吸收
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2017
·Vol. 6
·期 3
·558-567
·
IF 5.256
Xueai Li,Daxue Du,Chunsheng Wang,Haiyan Wang,Zhaopeng Xu
To satisfy the requirements of high-performance electromagnetic wave absorbers, composites of carbon and ferromagnetic metal with designed morphologies and abundant interfaces are highly desirable to balance impedance matching and attenuation. However, the synthesis of composites to meet these requirements and analysis of the electromagnetic wave energy loss mechanism remain great challenges. In this study, hierarchical rose-like assemblies of carbon–wrapped iron (Fe@C) nanoparticles with a porous structure were successfully synthesized via an in situ route using an iron alkoxide precursor with a rose-like morphology. Under the studied pyrolysis atmosphere and temperature, rose-like Fe@C and pure iron can be well modulated. The carbon shell is graphitic and highly ordered due to the catalytic effects of the iron nanoparticles, which affect the electromagnetic properties of the composites. The electromagnetic wave absorption properties of the Fe@C composite and iron are estimated in the frequency range of 2.0–18.0 GHz, and as expected, the hierarchical rose-like porous Fe@C demonstrates outstanding reflection loss characteristics with a minimum value of −71.47 dB with a thin matched thickness of 1.48 mm. Moreover, an ultra-wide response bandwidth (reflection loss of less than −10 dB) of 2.88–18.0 GHz is achieved. Analysis of the electromagnetic properties revealed that the hierarchical rose-like Fe@C presents very different electromagnetic functions in comparison to pure iron and Fe@C particles without the rose-like structure derived from the iron alkoxide precursor with the same structure. The carbon shells and special morphology with a certain microstructure can effectively regulate the complex permittivity and permeability to modify the impedance matching characteristic as well as enhance the attenuation ability via electromagnetic wave multiple reflection and scattering in the hierarchical rose-like Fe@C particles. Analysis of the attenuation constant and matched characteristic impedance validates that the enhanced electromagnetic wave absorption of the rose-like Fe@C with a porous structure is due to the significant enhancement of matched impedance and collective multiple loss mechanism.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 47
·22007-22016
·
IF 3.3
Yuxuan Zheng,Junping Zhao,Meifang Yan,Yuhua Gao,Haihua Li,Zhenfa Liu
Pudding-like Fe/C materials were successfully synthesized via an emulsion cross-linking method followed by a heat-treatment process. The morphologies and compositions can be easily controlled via adjusting the heat-treatment temperature. XRD, SEM, TEM, XPS, VSM, BET surface area measurements and zeta potential analysis were used to characterize the as-prepared samples. The adsorption capacity of MB (methylene blue) was systematically studied in different initial concentrations and pH of MB solution and at ambient temperature. Kinetics and isotherm synthesis were fitted well with the model of pseudo-second-order and Langmuir isotherms, respectively. The pudding-like Fe/C composites exhibited excellent adsorption performance in the removal of MB and the maximum adsorption capacity was 243.9 mg g−1, which was obtained for a 100 mg L−1 of MB solution at pH 7.0 and 25 °C. After ten cycles of adsorption experiments, the adsorption capacity can be maintained at about 93%, which indicated that the pudding-like Fe/C exhibited excellent adsorption stability and reusability.
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Hengyi Lu,Huanxiao Li,Chuyang Liu,Jiayi Shao,Fangqi Guo,Xiang Tian,Xiaopeng Li,Pan Ying,Yujing Zhang,Guangbin Ji
To tackle the complex electromagnetic pollution from advances in radar and network technologies, a simple, low-cost, and efficient absorbing agent has been developed. By optimizing the high-temperature sintering of the melamine/reduced iron powder composite system, we successfully created a Fe-C-N multiphase composite material with multi-level structure and dielectric-magnetic loss properties. The gas produced by the decomposition of melamine at high temperatures fosters the formation of a pore structure. Additionally, controlling the heating temperature and holding time effectively manages the phase transition path, allowing for synergistic evolution of the microstructure and regulation of the microwave-absorbing properties. The analysis of SEM images and XRD results identifies the synergistic enhancement mechanism between the multi-level structure and multi-phase. This endows a reflection loss of -75.91 dB at 5.16 GHz for samples held at 700°C for 3 hours (thickness 4.4 mm), with a maximum bandwidth of 4.92 GHz (1.6 mm). It avoids the traditional multi-step process of carbon/nitrogen doping, effectively regulating the phase transition path and microstructure evolution. This provides a new approach to develop lightweight, broadband microwave absorbing materials.
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Xuexue Zhang,Jing Wang,Weiwei Wang,Cao Wu,Chang Liu,Hailiang Deng,Liyan Wei,Weihua Gu,Wenbo Du,Yanning Chen,Hongwei Liu,Xun Cao
Using air/SiO 2 @Fe/C yolk-shell nanospheres (NSs) absorbers as a carrier, this research studies the coupling relationship between low-frequency electromagnetic wave (EMW) absorption performance and construction of materials with dual-sized pores and dual-component. Endured via synergistic process of pyrolysis and etching, the sizes of large cavities (∼ 200 nm) and mesopores (∼ 10 nm) were finely tuned at near-atomic scales. In addition, plenty of polarization attenuation structures (e.g., cavities/carbon, cavities/silica, iron/carbon and defects) were also generated. Results revealed that construction of multi-scale pores has slender contribution on the peak reflection loss (RL min ) values, while EMW absorption in the low-frequency range was obviously enhanced. The resulted H12 sample presented a resonance reductions at 6.72 GHz with the RL min value of −22.4 dB, which shifted ∼9.8 GHz towards lower frequencies compared to H0 (-20 dB, 16.52 GHz). This case can be elucidated via the resonance mechanism of cavity, where the air/SiO 2 @Fe/C yolk-shell NSs function as dielectric resonators. This work offers a novel way to design the micro/nano-scale pores in carbon-based EMW-absorbing materials, and a promising approach to develop materials designed for low-frequency EMW absorption.
研究领域:
材料科学
·
电磁学
·
纳米技术
·
微波吸收
✓ 已验证
产品关联
DOI
高影响因子
RUSSIAN JOURNAL OF GENERAL CHEMISTRY
·
2025
·Vol. 95
·期 6
·1455-1463
·
IF 0.8
Chen X.,Xiu X.,Zhuang X.,Sun H.,Dong C.
Developing cost-effective and efficient non-precious metal oxygen reduction catalysts (ORRs) is crucial for advancing renewable energy technologies. This study reports the synthesis and characterization of a novel non-precious metal catalyst, N–C–Fe-600, synthesized via a simple two-step method. Pyrolysis of NH 2 –MIL-88(Fe) under an inert atmosphere, followed by acidic treatment, yielded a porous N–C–Fe-600 material featuring a high surface area and a substantial concentration of active Fe–N x sites. Electrochemical characterization revealed that N–C–Fe-600 exhibits ORR activity comparable to commercial Pt/C catalysts, along with significantly enhanced stability and methanol tolerance. The catalyst demonstrates a near-ideal four-electron transfer pathway, suggesting its potential as a viable alternative to platinum-based catalysts in fuel cells.
研究领域:
材料科学
·
电化学
·
催化
·
纳米技术
·
能源技术
✓ 已验证
DOI
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2026
·
IF 3.4
Wang Xiaoqi,Yang Pengwei,Yu Linzhu,Jiang Haoxuan,Ma Jingxiang,Ma Xiangshuai,Ma Shuangchen
Electrochemical nitrogen reduction reaction (eN2RR) is a highly promising approach for ammonia synthesis under normal temperature and pressure conditions. However, its practical application is limited by the low activity and selectivity of the catalysts. In this study, a series of Fe-MOFs materials were prepared by hydrothermal method, and further sintered to obtain Fe@C materials. The electrocatalytic performance of these materials in eN2RR was systematically investigated. The results showed that MIL-53(Fe)-2 exhibited excellent catalytic activity at -0.4 V vs. RHE, with an ammonia production rate of 1.443 µg·h⁻¹·mg⁻¹ and a Faradaic efficiency of 5.972%. In contrast, the Fe@C material derived from MIL-53(Fe)-1, although having rapid activation characteristics within a narrow potential window, did not perform as well as the former. This work provides a new material strategy and experimental basis for the design of iron-based eN2RR catalysts.
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DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 7
·1-8
·
IF 5.479
Yang Fencheng,Jiang Guodong,Yan Feng,Chang Qing
Iron-carbon (Fe/C) magnetic nanocubes were synthesized by direct pyrolysis of Prussian blue nanocubes under an inert gas atmosphere. They are shown to possess intrinsic peroxidase mimicking activity to catalyze the oxidation of peroxidase substrate N , N -diethyl- p -phenylenediamine sulfate salt to form a purple colored product in the presence of H 2 O 2 . The values for K m and V max are 74 μM and 46 nmol s −1 , respectively. Steady-state kinetic analysis also indicates that the catalysis reaction follows a ping-pong mechanism. Based on these findings, an ultrasensitive colorimetric H 2 O 2 assay was worked. Absorbance (best value measured at 550 nm) increases linearly in the 10 nM to 0.2 mM H 2 O 2 concentration range, and the limit of detection is 1.5 nM. The method was also applied to the quantification of glucose, which is oxidized by glucose oxidase in the coexistence of H 2 O 2 . The response covers the 0.1 to 500 μM glucose concentration range, and the limit of detection is 16 nM. The method was applied to the determination of H 2 O 2 in rainwater samples. The glucose assay was used to analyze serum samples, and satisfactory results were obtained. Other attractive features include good chemical activity, low cost, easy storage, and high catalytic efficiency.
Schematic presentation of converting Prussian blue nanoparticles into Fe/C magnetic nanocubes by a pyrolysis technique and the use of glucose oxidase and Fe/C magnetic nanocubes to establish a one-step spectrophotometric method for the determination of glucose and hydrogen peroxide.
研究领域:
纳米技术
·
分析化学
·
生物传感器
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Jizhi Zhou,Pei Liu,Zeyuan Liu,Jia Zhang,Xin Huang
The recovery of phosphorus (P) from wastewater has attracted substantial attention with the atrophy of global P resource. In the current work, the simultaneous recovery of P with the removal of nickel (Ni) via iron/activated carbon (Fe/AC) and hydrogen peroxide (H 2 O 2 ) form nickel-plating wastewater was achieved. The isotherm reaction showed a maximum P recovery of 99.99% with an equilibrium concentration of P of 0.12 mg/L, which was lower than the limitation of discharge regulation (China national regulation, 0.5 mg/L). The optimal conditions for P recovery were 0.25 mol/L H 2 O 2 , a Fe/AC mass ratio of 1:1, an at 60 °C, which led to the ratio of P in the form of FePO 4 in the residue to be 77%. Moreover, the Fe/AC microelectrolysis coupling to H 2 O 2 promoted Fe 2+ production from Fe 0 and improved the circulation of Fe 2+ , which improved the production of hydroxyl radicals with increasing pH and consequently enhanced oxidation efficiency of hypophosphite. The FePO 4 was found the major form of phosphate in the precipitate. The highest removal rate of nickel was 89%, which was attributed to its precipitation at high pH and adsorption on to iron hydroxides and activated carbon. Nickel purification was achieved by further coagulation as the equilibrium concentration of Ni was lower than 0.1 mg/L. Therefore, our work provides a promising approach for simultaneous recovery of P and removal of Ni from electroplating wastewater.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
WATER ENVIRONMENT RESEARCH
·
2026
·Vol. 98
·期 2
·e70317
·
IF 2.8
Wenxiao Zhang,Chenzhi He,Ji Tang,Wei Wang,Yanyan Guo,Youcai Zhao,Tao Zhou
Anaerobic digestate, a typical by-product of large-scale biogas plants, faces mounting disposal pressure due to the rapid increase in organic solid waste. In this study, an iron-carbon composite was produced from digestate through polyethylene glycol (PEG)-assisted iron modification followed by low-temperature carbonization. The resulting material exhibited a mesoporous texture, oxygen-containing surface functionalities, and Fe 3 O 4 /Fe 3 C domains, enabling efficient removal of Congo red in batch systems. Removal was favored under mildly acidic conditions. At pH 4 and 298 K, the maximum experimentally observed equilibrium uptake reached 1267.35 mg·g −1 at high initial concentration, and removal efficiencies approached 99% under the tested conditions. The adsorbent retained more than 95% of its initial removal performance after five regeneration cycles. Kinetic and equilibrium analyses, together with FTIR/XPS and post-adsorption characterization, support that uptake involves Fe-associated interactions, electrostatic effects, and hydrogen bonding, with additional high-coverage accumulation contributing at elevated concentrations. Overall, this work demonstrates a practical route to valorize anaerobic digestate into a reusable adsorbent for removing azo dyes from wastewater. Graphical Valorizing anaerobic digestate into a magnetically recoverable Fe-C adsorbent enables efficient Congo red removal: near-complete decolorization at pH 4, 298 K, maximum observed q e 1267.35 mg·g −1 , and > 95% performance after 5 cycles. A single-step, low-temperature process offers a scalable, low-cost wastewater solution.
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Shanxin Li,Yijing Sun,Fanjian Meng,Xuzhou Jiang,Hongying Yu
Effective integration of multiple functions into microwave absorbing materials is a future development direction, but still remains a significant challenge. This work fabricated a lightweight, multifunctional aerogel through electrostatic self-assembly, freeze-drying and in-situ pyrolysis process, achieving an in-situ composite of magnetic/dielectric components. The regulated pyrolysis temperature achieves a good balance between abundant nanopores and heterogeneous interfaces, enriched defects, and conductivity. This balance induced a synergy of dielectric loss, magnetic loss, and conduction loss at low frequencies, improving the impedance matching. The aerogel obtains a minimum reflection loss (RL min ) of −65.17 dB in the low-frequency range and a maximum effective absorption bandwidth (EAB max ) of 5.76 GHz. The radar cross section (RCS) simulation confirmed its good stealth performance. In addition, an increase in aerogel loading enhanced its electrical conductivity, resulting in a higher electromagnetic interference (EMI) shielding effectiveness (SE) of 81.83 dB, the specific shielding effectiveness (SSE) up to 359.28 dB·cm 3 /g and the absolute shielding effectiveness (SSE t ) up to 1596.82 dB·cm 2 /g. Beyond microwave absorption and shielding, this aerogel also exhibited good hydrophobicity and thermal insulation. This study provides a new perspective for the development of materials with microwave absorption properties in low-frequency bands and multifunctional properties for broader applications in military, communication, aerospace, and other fields.
研究领域:
材料科学
·
电磁学
·
纳米技术
✓ 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）