Journal of Materials Research and Technology-JMR&T
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2024
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IF 6.2
Qian Ma,Rong Qiang,Yulong Shao,Xiao Yang,Yi Chen,Rui Xue,Fangjie Ren,Yuancheng Ding,Lei Rong,Jingbo Fang,Qing Miao,Zheng Guo
Nowadays, the issue of electromagnetic pollution has become increasingly prominent, underscoring the critical importance of developing high-performance microwave absorbers. This study put forwards the synthesis process of two-dimensional (2D) FeCo/Co 8 FeS 8 /C carbon nanosheets, wherein CoSO 4 and FeCl 3 serve as inorganic salt templates, and dopamine functions as the carbon source. FeCo alloy nanoparticles and Co 8 FeS 8 nanoparticles are loaded on the surface of the carbon layer. 2D structure forms the conductive network, which proves advantages in establishing efficient electronic channels and minimizing conduction losses. The carbon component increases the dielectric constant of the composite and improves its impedance matching, and the FeCo alloy provides a certain ML. The synergistic effect between these components significantly contributes to the exceptional microwave absorption performance of the composites. Accordingly, the minimum reflection loss ( R L min) of FeCo/Co 8 FeS 8 /C composite reaches −47.4 dB, its effective absorption bandwidth (EAB) reaches 5.3 GHz. In particular, CST confirms that radar cross-section reduction value of FeCo/Co 8 FeS 8 /C composite can reach 20.2 dB m 2 in the range of −90° < phi< 90°, indicating a high microwave attenuation ability. The study introduces a novel strategy for advancing the development of two-dimensional carbon-based absorption materials.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2019
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IF 5.155
Weiguang Fang,Peng Dai,Haibo Hu,Tongtong Jiang,Huaze Dong,Mingzai Wu
Simultaneous acquisition of satisfactory bifunctional activities toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) for single transition metal sulfides is challenging, which greatly restrict their applications as cathode catalysts in the rechargeable Zn-air batteries (ZABs). Herein, Fe 0.96 S/Co 8 FeS 8 nanoparticles co-embedded in 3D porous N, S codoped carbon (Fe 1 Co 1 S x @NSPC) were fabricated with regulated ratio of iron to cobalt. Compared with single iron sulfide catalyst (Fe 0.96 S@NSPC), the obtained Fe 1 Co 1 S x @NSPC exhibits enhanced activities in both ORR and OER , whose half-wave potential and overpotential (at 10 mA cm −2 ) are 0.82 V, 0.39 V. The improved electrocatalytic activities are believed to be from the synergistic effects between the binary sulfides and the N, S co-doping and the 3D porous structures. As expected, the home-made aqueous ZAB based on Fe 1 Co 1 S x @NSPC exhibits a high peak power density (159 mW cm −2 ), large specific capacity (807 mAh g −1 ) and a long-term charge/discharge cycling stability over 378 cycles at about 852 mV. Moreover, the self-made all-solid-state button ZAB based on Fe 1 Co 1 S x @NSPC shows a high peak power density (71 mW cm −2 ) and a well maintained cycle life at about 841 mV over 100 charge/discharge cycles.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2019
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IF 3.372
Kehan Zhou,Dongmei Tang,Wenlong Li,Yue Han,Huayu Wu,Guowang Diao,Ming Chen
In this paper, bimetallic sulfide Co 8 FeS 8 /N-C dodecahedral nanocages (DNCs) were synthesized by using ZIF-67 as a template through subsequent pyrolysis and sulfuration process. Co 8 FeS 8 nanoparticles are embedded carbon framework, which has porous hollow interior and conductive N-doped carbon matrix. When the Co 8 FeS 8 /N-C DNCs were applied as anode materials in lithium-ion battery, the bimetallic sulfide composites realize high reversible capacity (396 mA h g −1 at 0.5 A g −1 after 400 cycles) and excellent rate capability (349 mA h g −1 at 5.0 A g −1 ). Meanwhile, Co 8 FeS 8 /N-C DNCs also have superior cycle performance (308 mA h g −1 at 5.0 A g −1 after 1000 cycles). The remarkable properties are attributed to the synergy effect of bimetallic sulfide and the special polyhedral hollow structure with the conductive N-dopped mesoporous carbon.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2020
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IF 7.632
Lu Chen,Li−Li Cui,Zizhun Wang,Xingquan He,Wei Zhang,Tewodros Asefa
Efficient, durable, nonprecious metal-based catalysts for electrochemical reactions involving oxygen are needed to advance the widespread use of fuel cells and Zn-air batteries. In this work, hybrid materials composed of bimetallic (Co and Fe) sulfide (Co8FeS8) nanoparticles supported on N,S-doped carbon microparticles that can serve as dual-function oxygen electrocatalysts are synthesized. The synthesis of the materials is performed by preparing and then pyrolyzing silica-protected Fe- and Co-modified, S-containing polyphthalocyanine at different temperatures. The materials are named (Fe,Co)SPPc-T-sp, where T denotes the pyrolysis temperature and sp represents the silica protection applied for their synthesis. Among them, the material synthesized at 900 °C, denoted (Fe,Co)SPPc-900-sp, shows superb electrocatalytic activities in an alkaline solution both toward the oxygen reduction reaction (ORR), with a half-wave potential (E1/2) of 0.830 V vs RHE, and toward the oxygen evolution reaction (OER), with a current density of 10 mA cm–2 at an overpotential (η10) of 353 mV. The catalytic activities of this material for both reactions are comparable with those of the respective benchmark, precious-metal-based catalysts, namely, Pt/C (20 wt %) and RuO2, respectively. An alkaline Zn-air battery assembled using (Fe,Co)SPPc-900-sp as an air electrode delivers a high peak power density (158.6 mW cm–2) and outstanding charge–discharge cycling stability (for over 50 h). These catalytic performances are better than those of the corresponding battery containing Pt/C and RuO2 electrocatalysts. This work also offers a facile synthetic strategy for the fabrication of robust, inexpensive dual-function electrocatalysts for Zn-air batteries.
研究领域:
材料科学
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电化学
✓ 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）