Surfaces and Interfaces
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2024
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IF 5.7
Zhaolin Xu,Xiangnan Chen,Shaoxi Zhang,Ruohao Li,Guangjun Gou
With the development of communication and automatization technology, the demand for electromagnetic absorbing materials is continuously rising. The key problem lies in expanding and regulating the electromagnetic absorption band . Among these materials, carbonized polymers stand out in terms of electromagnetic absorption due to their lightweight, low cost and designability. The carbonized polymers can bridge varies of substances to construct lightweight nitrogen-doped carbon composites, achieving broadband and tunable-band designs. In this study, Fe-C-N anchored TiO 2 hierarchical structure is simply realized by carbonizing polypyrrole/MXene precursors. FeCl 3 are designed to be as the initiator for the polymerization of pyrrole and in situ as a doping Fe source. Moreover, by controlling the carbonization temperature, the electromagnetic absorption band can be obviously regulated from C to Ku band. The multi-layered TiO 2 structure brings enhanced structural losses and better electromagnetic energy dissipation pathways, while the crystalline/amorphous interfaces and hybridizations between Fe-C-N and TiO 2 boost the interfacial polarizations and dipole polarizations. Besides, the introduction of Fe compounds leads to ferromagnetism and magnetic losses, which improves the impedance matching. This work provides referencing ways for the design of broadband electromagnetic absorbing materials.
研究领域:
材料科学
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
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IF 3.927
Cui Wang,Qiangqiang Yang,Zhenhong Li,Kun-Yi Andrew Lin,Shaoping Tong
A magnetic carbon-coated Fe-C/N composite was synthesized by a simple impregnation method and its performance in activating persulfate (PS) to degrade Acid Red 73 (AR 73) was investigated. The as-prepared carbon-coated Fe-C/N hybrid material was characterized via transmission electron microscopy , Raman spectra, X-ray diffraction and X-ray photoelectron spectrum. Degradation experiments showed that 98.11% of AR 73 could be degraded in 10 min, but its COD was partly removed. The effects of initial reaction pH and temperature were also evaluated. An increase of temperature was beneficial for the removal of AR 73, while the increase of pH had an opposite result. The activation energy of the AR 73 degradation was determined to be 46.12 KJ/mol, smaller than those in relative literatures. The recycling test showed that the carbon-coated Fe-C/N composite had good stability. The mechanism study indicated that the catalytic performance of Fe-C/N was due to the synergistic effect between Fe 3 C and Fe 3 N, and the N doped carbon shell suppressed the rate of Fe leaching, thus enhancing its stability.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
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IF 15.1
Gang Fang,Chuyang Liu,Xinyu Wei,Qinyu Cai,Chi Chen,Guoyue Xu,Guangbin Ji
Regulating the inner defects could lead to transformation of the prominent dielectric loss for the microwave absorbers, which is a necessary foundation to explore the preference type of dielectric loss mechanism. Herein, in this work, selective molar ratios of melamine/cetyl trimethyl ammonium bromide (CTAB) precursors were designed to construct the Fe/C/N based hybrid materials. The results demonstrate that the dominated polarization loss can be obtained with the high molar ratio of melamine/CTAB due to the improved level of defects density such as point defects, heterointerface distortion, etc . Differently, it is easy to obtain the conductive carbon phase and high crystallinity degree of Fe 3 C with a low melamine/CTAB molar ratio, achieving significantly conductive loss. Finally, the Fe/C/N hybrid with dominant polarization loss harvests a broad bandwidth of 6.2 GHz at 1.7 mm, verifying the superiority of polarization loss for enhancing electromagnetic absorption performance. Furthermore, simulation results prove that this composite possesses the desirable radar cross section (RCS) reduction and electromagnetic protection for the human head, indicating the potential applications in both military and civilian fields.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
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.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Li Zhu,Jing Ma,Yuyu Wang,Song Qiao,Yifan Wu,Min Xu,Wenxin Ji,Yonggang Sun,Yulong Ma
The full-component decomposition and reorganization of inert coal gasification fine slag (CGFS) could be achieved through exogenous enhancement, and this approach was also an inevitable choice for enterprises to realize clean production. In this work, a strategy for activating the CGFS structure via non-metallic heteroatomic nitrogen doping was proposed. CGFS was subjected to mechanical ball milling to obtain ball-milled CGFS (MCGFS), and the carbon-ash synergistic catalyst N d -MCGFS was further synthesized through dicyandiamide doping and hydrothermal treatment. The flotation-derived residual carbon (RC) and ball-milled inorganic minerals (MIM) were also prepared the composites N d -RC and N d -MIM under the same conditions. Under suitable conditions, the N d -MCGFS/PMS system achieved a BPA removal rate of 97.00 % within 60 min. The prepared N d -MCGFS had a nitrogen content of 0.73 %, an Fe N structure proportion of 18.80 %, and a specific surface area of 132.07 m 2 /g, while catalysts using RC or MIM alone as substrates showed inferior performance The mineral-based N d -MIM only achieved 45.81 %, while the residual carbon-based N d -RC mainly relied on adsorption. The residual carbon pores and mineral metal sites could promote carbon-ash synergy and enhance catalytic performance. In the N d -MCGFS/PMS system, PMS was activated by C O bonds and nitrogen species to generate reactive oxygen species (ROS). BPA degradation was realized through the cycle of high-valent iron‑oxygen species and electron transfer. The Fe leaching amount was approximately 43 times lower than that of the CGFS. This provides a new approach for the high-value utilization of CGFS.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Hongyu Zhang,Fengying Zhang,Antong Shi,Jiahan Yang,Zhehan Tu,Weixin Lin,Xue Bai,Gongduan Fan,Zhuwu Jiang
The design and catalytic potential of materials with simultaneously oxidation and reduction performance remains underexplored, particularly in three-dimensional electrochemical systems. This study developed a carbon nanosheet framework with iron insertion and nitrogen doping, as the skeleton for the deposition of. nickel‑manganese metal mixture. Advanced characterization confirmed that the addition of Fe/C-N skeleton can improve morphology and specific surface, which in turn enhances electronic conductivity and degradation efficiency. Electron paramagnetic resonance (EPR) and density functional theory (DFT) calculations certify that the Fe/C-N skeleton can enhance the electron supply capacity and thereby accelerate the generation and stabilization of •H and •OH species during the reaction. Under optimal conditions, the system achieved a maximum Chloracetamide (MCAcAm) degradation rate of 68.86 % and good stability. Moreover, in practical tests using industrial wastewater pre-treated with chlorination, the composite showed exceptional efficiency, achieving 86.14 % chemical oxygen demand (COD) and 74.01 % total organic carbon (TOC) removal within 1 h. These results highlight the potential of NiMn-LDH/MnO 2 -Fe/C-N (Name it NML-Fe/C-N) for practical wastewater treatment and provide valuable insights into the design of advanced electrode materials and the mechanisms of electrocatalytic degradation.
研究领域:
环境科学
·
电化学
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材料科学
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水处理技术
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催化
·
废水处理
✓ 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）