Journal of Energy Storage
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2024
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IF 8.9
Jizhao Zou,Tao Liang,Minggui Peng,Peng Liu,Zhe Li,Jiaming Wen,Zhangjian Li,Yusheng Yan,Xin Yu,Xierong Zeng,Junfeng Huang
Integration of cations doping by using unpaired high-spin electrons through the valence state substitution is deemed as a prospective strategy for construction of oxygen vacancies, regulation of inner electronic structures and enhancement of surface properties. Herein, an effective strategy is proposed to construct massive oxygen vacancies into 2D nitrogen-doped carbon nanosheets by the design of heterogeneous interfaces between CoFe alloy and CoFe 2 O 4 nanoparticles. The valence state transition for Fe and Co endows electronic transfer capability and charge density around the oxygen atoms. The prepared CoFe-CoFe 2 O 4 @NCs-4 catalyst exhibits maximum content of oxygen vacancies (Density of O vac 50.1 %). It shows excellent ORR activity with a half-wave potential of 0.83 V and OER overpotential of 320 mV. Reversible Zn-air batteries assembled by the CoFe-CoFe 2 O 4 @NCs-4 catalysts exhibit a power density of 106.32 mW cm −2 and durable stability (500 h at the current density of 10 mA cm −2 ), which also are superior to those of the commercial 20 wt% Pt/C + RuO 2 catalyst. The excellent bifunctional catalytic performance can be attributed to synergistic effects between massive oxygen vacancies, ultrahigh specific surface area (545.9 m 2 g −1 ) and heterogeneous interfacial structure. This work provides valuable insight into designing efficient bifunctional oxygen electrocatalysts for rechargeable Zn-air batteries.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2016
·Vol. 4
·期 24
·9455-9465
·
IF 8.262
Haiming Sun,Xijia Yang,Lijun Zhao,Tianhao Xu,Jianshe Lian
Here we report a flexible one-pot hydrothermal synthesis of an octahedral CoFe/CoFe2O4 submicron composite used as a superior Fenton-like catalyst for the decomposition of organic pollutants in water. As a peroxymonosulfate (PMS) catalyst, the non-toxic CoFe/CoFe2O4 submicron composite can highly efficiently decompose Orange II (30 mg L−1, 1.5 min and 60 mg L−1, 3 min). Especially, the CoFe/CoFe2O4 submicron composite exhibits better generalization for the degradation of different organic pollutants and excellent reusability due to its large size and structural stability. Furthermore, its high saturation magnetization (123.7 emu g−1) makes it convenient to magnetically separate from aqueous phase after catalysing the reaction, and its relatively large size is conducive to solving or minimizing secondary pollution. Meanwhile, the probable mechanism of PMS activation with CoFe/CoFe2O4 catalyst is proposed.
研究领域:
环境催化
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材料化学
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水处理技术
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纳米材料
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高级氧化工艺
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DOI
高影响因子
ELECTROCHIMICA ACTA
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2022
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IF 7.336
Min Jiang,Rui Dong,Hanxiao Liao,Yong Liu,Yuan Wang,Pengfei Tan,Jun Pan
Rational fabrication of an electrocatalyst with excellent stability, conductivity, and activity is urgently demanded for oxygen evolution reaction (OER). In this work, Ru-regulated hierarchical CoFe/CoFe 2 O 4 nanoparticles with graphitic carbon shells were successfully fabricated via self-assembling and vapor reduction strategies. Our investigation uncovers high concentrations of octahedral Co 3+ sites in electrocatalysts can be triumphantly acquired via moderate Ru doping, which could give rise to excellent electrocatalytic activities during OER. In addition, the design of CoFe alloys and graphitic carbon shells can compensate for the weak conductivity of cobalt ferrites. Based on the intrinsic stability, improved conductivity and activity, the as-prepared electrocatalyst yields a low overpotential of 237 mV at 10 mA cm −2 and a small Tafel slope of 47 mV dec −1 in 1.0 M KOH electrolyte, exhibiting outstanding electrocatalytic activities for OER.
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
CARBON
·
2025
·
IF 11.6
Shuai Liu,Shu Li,Shaoli Guo,Yan Cui,Minghan Dai,Zelin Wang,Guoxiang Chen
The composite engineering of dielectric-magnetic systems has demonstrated significant potential for enhancing the electromagnetic wave absorption (EWA). Despite advances, achieving uniform in-situ growth of highly dispersed magnetic particles on carbon matrices remains technologically challenging. This study proposes an integrated freeze-drying and carbonization strategy, successfully fabricating CoFe@CoFe 2 O 4 /C aerogel, featuring carbon nanosheets uniformly decorated with in-situ grown core-shell magnetic particles. The carbon aerogel annealed at 700 °C exhibits exceptional impedance matching and EWA characteristics, achieving an ultrawide effective absorption bandwidth of 7.84 GHz (10.16–18 GHz) at an optimized thickness of 2.63 mm. The outstanding absorption performance is attributed to the electromagnetic coupling between core-shell magnetic architectures and conductive carbon networks. First-principle calculations reveal dielectric polarization loss arising from interfacial heterogeneities and defect engineering in aerogels. Simultaneously, the hierarchical porosity endows the aerogel with superior thermal insulation. These integrated attributes position the aerogel as a multifunctional platform for EWA applications and advanced radar-infrared compatible stealth systems.
研究领域:
材料科学
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电磁学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Energy Technology
·
2026
·Vol. 14
·期 8
·e70612
·
IF 3.6
Jianguang Jia,Yue Cui,Chunfeng Shi,Haijun Hao
Developing a sustainable and cost-effective counter electrode (CE) material with high catalytic activity is of significant importance for quantum dot-sensitized solar cells (QDSSCs). In this work, by using the industrial residue material of sulfonated asphalt as the carbon precursor, we prepared a CoFe/CoFe 2 O 4 embedded N, S-doped carbon hybrid (CoFe/CoFe 2 O 4 @C) and applied to the CE of QDSSC. Structure analyses indicated that CoFe/CoFe 2 O 4 @C has a porous structure with large surface area. Electrochemical investigations revealed that the CoFe/CoFe 2 O 4 @C possesses high catalytic activity for polysulfide reduction. Consequently, CdSe QDSSC based on CoFe/CoFe 2 O 4 @C CE achieved a high power conversion efficiency (PCE) of 6.37%, significantly superior to the commonly used PbS CE (5.4%). This study provides a sustainable strategy for converting the industrial residue material of asphalt into a low-cost and high-performance CE material for QDSSC.
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DOI
高影响因子
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