RENEWABLE ENERGY
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2022
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IF 8.634
Yuanting Lei,Lili Zhang,Danni Zhou,Chengli Xiong,Yafei Zhao,Wenxing Chen,Xu Xiang,Huishan Shang,Bing Zhang
Electrocatalytic overall water splitting is considered to be a promising strategy for hydrogen production . However, the development of high-efficient and robust bifunctional catalysts with earth-abundant elements for water splitting is of great significance. Herein, interconnected CoFe alloy nanosheets supported on NiO nanosheets (NiO/CoFe alloy) were synthesized on carbon cloth via a simple electrochemical activation of NiO/CoFe-layered double hydroxide (NiO/CoFe-LDH). The as-prepared NiO/CoFe alloy exhibits excellent activity and durability toward HER (hydrogen evolution reaction) and OER (oxygen evolution reaction). Impressively, it requires comparatively low overpotentials of 218 and 280 mV to deliver the current density of 10 and 30 mA cm −2 for HER and OER in 1.0 M KOH, respectively. The superior catalytic behavior may derive from the interconnected nanosheets structure, abundant exposed active sites, and the fast electron transfer of NiO/CoFe alloy. This work may shed light on the rational construction and design of precious metal-free catalysts with remarkable performance for overall water splitting and beyond.
研究领域:
材料科学
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电化学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Jiawei Du,Mengyi Zhang,Peng Tang,Liwen Zhang,Xueying Zhao,Xiaolu Zhan,Bo Wang,Jianjun Zhao,Nana Liu,Guohua Wu,Xuyang Zhang
The development of low-frequency absorption materials is pivotal for the significant reduction of electromagnetic interference and the enhancement of the electromagnetic environmental quality. Further research is essential to deepen and expand the scope of low-frequency absorption studies. In this study, nanoscale CoFe/C composite materials were synthesized from cobalt-iron bimetallic metal-organic frameworks (MOFs) via a hydrothermal synthesis process, followed by heat treatment. The dispersion of CoFe alloy particles and the morphology of the composites were effectively controlled by modulating the cobalt-to-iron element ratio in the precursors, thereby optimizing the absorption capabilities in a mid-low frequency range. The prepared Co 3 Fe 7 /C composite achieved a notable minimum reflection loss (RL min ) of −55.05 dB in the C-band at a thickness of 3.46 mm, with an effective absorption bandwidth (EAB) of 2.2 GHz (5.40–7.60 GHz), covering 55 % of the C-band. Furthermore, at a thickness of 1.67 mm, the EAB was extended to 5.12 GHz. The nanoscale core-shell structured CoFe alloy/carbon composites demonstrate considerable potential as exceptional low-frequency absorption materials, due to their favorable dispersion, high magnetic responsiveness, and the presence of numerous heterogeneous interfaces.
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
ELECTROCHIMICA ACTA
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2021
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IF 6.901
Zihao Cui,Xizhuang Liang,Peng Wang,Peng Zhou,Qianqian Zhang,Zeyan Wang,Zhaoke Zheng,Yuanyuan Liu,Ying Dai,Baibiao Huang
Developing highly efficient and stable electrocatalyst for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is critical for overall water splitting to solve the shortage of fossil fuel and environment pollution, but it is full of obstacles and challenges. Fe 3 N@Co 4 N@CoFe alloy nanoparticles were prepared by using an in situ coupling method. The obtained catalyst showed a satisfactory OER performance in alkaline solution with a low overpotential of 225 mV at 10 mA cm −2 current density and a small Tafel slope of 48 mV/dec. Meanwhile, the HER performance was also improved in alkaline solution after cyclic voltammetry (CV) cycles of OER due to the formation of CoFe oxyhydroxides, which required an overpotential of 135 mV to achieve 10 mA cm −2 current density and a Tafel slope of 109 mV/dec. More importantly, the obtained Fe 3 N@Co 4 N@CoFe alloy electrode and Fe 3 N@Co 4 N@CoFe alloy-CV electrode (treated through CV cycles of OER) were used as anode and cathode to assemble a two-electrode system for overall water splitting. The constructed system displayed an impressive competency with a voltage of 1.59 V at 10 mA cm −2 current density. The prepared electrocatalysts demonstrated superb long-term stability under 50 mA cm −2 current density for OER, HER and overall water splitting.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
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2025
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IF 21.1
Linhao Wang,Jia Wei,Jiangkai Huo,Wei Ji,Xiaohui Zhang,Yanan Li,Jiamei Li,Nan Cui,Wenhao Yan,Yuxin Zhao,Jun Li,Ju Wang
Herein, an electron-optimized core-shell CoFe alloy-carbon composite (CoFeC) was developed from prepared CoFe Prussian blue analogues (CoFe PBAs) through pyrolysis and applied for peracetic acid (PAA) activation. Characterization analysis and theoretical calculations indicated that the Co sites as the primary active centers, with the presence of C and Fe in CoFeC significantly narrowed the difference between the d-band center ( Ɛ d ) and the Fermi level ( E F ), thereby reducing PAA adsorption energy on Co sites and enhancing electron transfer. The identification of reactive species confirmed that acetylperoxy radicals (CH 3 C(O)OO·) and singlet oxygen ( 1 O 2 ) were the dominant species driving the reaction. The CoFeC/PAA system demonstrated exceptional pollutant degradation efficiency, achieving nearly 100% removal within 30 min, along with strong interference resistance and high durability in continuous-flow reactors. This work provided novel insights into the activation of PAA by bimetallic carbon catalysts and offered guidance for the development of efficient and sustainable water treatment technologies.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Xueying Wang,Haoshan Xu,Shuhong Huang,Xiaoxi Zeng,Ling Li,Xiaohui Zhao,Wenming Zhang
Herein, a novel MOF-derived trifunctional electrocatalyst with a three-dimensional hierarchical structure of N -doped carbon nanofibers (NCNFs) compounded with vertically grown nanosheets loaded with Co and CoFe alloy nanoparticles is reported. It is found that Co/CoFe NAs@NCNFs has a good half-wave potential of 0.83 V for ORR, the overpotential of 290 mV and 103 mV for OER and HER, respectively. When Co/CoFe NAs@NCNFs catalyst is employed on the cathode of a microbial fuel cell (MFC), the peak power density of the MFC can reach 2139.6 ± 43 mW m −2 , which is 1.56 times better than that of commercial Pt/C. Furthermore, the assembled MFCs can also successfully drive the water splitting. The above excellent performance is mainly due to the structure of the interwoven NCNF networks combined with nanosheets which greatly enhances the surface area and mass transfer capacity of the material, and the loaded nanoparticles are constructed into a large number of Fe-N x -C and Co-N x -C active sites, further increasing the catalytic performance of Co/CoFe NAs@NCNFs. This work could provide a novel approach to the regeneration and conversion of clean energy.
研究领域:
材料科学
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能源科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
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2024
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IF 10.7
Chao Yuan,Jialing Sheng,Shuke Guo,Xiaoyu Wang,Jiangyan Xu,Hongmei Jiang
In this work, a magnetic CoFe alloy and Co supported on mesoporous carbon with abundant defects (CoFe–Co/MC) was prepared by a sol–gel method combined with calcination and applied to activate peroxymonosulfate (PMS) and efficiently remove bensulfuron methyl (BSM) from water. CoFe–Co/MC could degrade 95% of BSM, while Co or Fe without supported mesoporous carbon could only provide degradation efficiencies below 10%, indicating that the introduction of mesoporous carbon could effectively enhance catalytic activity. Moreover, the dissolution of Co2+ from CoFe–Co/MC is only 0.22 mg L−1, which is about 20% of Co/MC, indicating that the bimetallic composite effectively inhibits the dissolution. The results of radical scavenger and EPR experiments demonstrated that 1O2 played the leading role in degradation process, while SO4˙− and small amounts of ˙OH and O2˙− were also involved in the degradation. The results of p-BQ scavenger and N2 atmosphere experiments showed that 1O2 mainly originated from the interaction between carbon defects and dissolved oxygen. The degradation performance of the CoFe–Co/MC/PMS system, carbon defect content and 1O2 content all increased with the increase of pyrolysis temperature, which demonstrated that adjusting pyrolysis temperature can regulate carbon defect content and 1O2 content, further improving catalytic activity. Possible BSM degradation pathways of CoFe–Co/MC/PMS were investigated in detail. This research provides new insights into the design and construction of metal–carbon catalysts rich in carbon defects and reveals how to regulate carbon defect content, 1O2 content and catalytic performance.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2023
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IF 6.2
Jun Liu,Zhou Peng Li,Bin Hong Liu
We report our facile and efficient approach for synthesizing Co-Fe alloy based oxygen reduction reaction (ORR) catalysts, in which alloy nanoparticles are encapsulated in nitrogen-doped carbon nanostructures . The catalysts with high hierarchical porosities are fabricated at an appropriate temperature of 775 °C without a further acid leaching treatment after pyrolysis due to the use of ZnO nanoparticles as auto-removable templates. Co/Fe atomic ratio is found to greatly influence the ORR catalytic activity. The catalyst with Co/Fe = 1 exhibits the best catalytic performance by showing an ORR onset potential of 0.99 V and a half-wave potential of 0.87 V (vs. RHE) in 0.1 M KOH, as well as 0.98 V and 0.83 V (vs. RHE) in 0.5 M H 2 SO 4 , better than or approaching the performance presented by a commercial 28.6 wt% Pt/C catalyst. The Zn-air battery using the synthesized CoFe@N-C catalyst delivers a higher power density at ambient conditions by air-breathing than the one using the 28.6 wt% Pt/C catalyst. Relatively higher atomic concentrations of both Fe and Co as well as more graphitic nitrogen in the surface of CoFe@N-C detected by X-ray photoelectron spectroscopy (XPS) may account for its excellent ORR catalytic activities both in alkaline and acidic environments.
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
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2025
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IF 9.7
Bin Cui,Yunfeng Zhu,Chang Li,Wei Zhou,Mengran Li,Jiabao Bai,Yana Liu,Jiguang Zhang,Rui Shi,Jun Wang,Jian Yang
The development of cost-effective, highly-active, and stable oxygen reduction reaction (ORR) electrocatalysts is crucial for advancing fuel cells and metal-air batteries. Herein, we report a two-step thermal treatment strategy for successfully introducing heteroatoms and CoFe alloys onto Vulcan XC-72R to prepare efficient electrocatalysts. Among the synthesized electrocatalysts, the N, F co-doped catalyst (CoFe/NFC) demonstrates optimal ORR performance in alkaline medium. Notably, moderate heteroatom doping generates high specific surface area, large pore volumes, and optimal carbon defects, facilitating both active site accessibility and mass transport. Density functional theory calculations reveal that the N F synergistic effect enhances metal-support interaction and optimizes *OH adsorption energy. Attractively, aluminum-air batteries equipped with CoFe/NFC cathodes present outstanding performance: a peak power density of 187.9 mW/cm 2 , a large specific capacity of 586 mAh/g Al , and stable operation for 720 min at 50 mA/cm 2 . This study offers valuable insights into heteroatom doping strategies, which may facilitate the rational design of carbon-based electrocatalysts with enhanced catalytic performance.
研究领域:
材料科学
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电化学
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能量存储与转换
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催化
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纳米材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
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IF 8.355
Dahu Ding,Shengjiong Yang,Liwei Chen,Tianming Cai
Developing carbon-based hybrid catalysts with high reactivity, good stability, and low cost is critical for environmental remediation via heterogeneous advanced oxidation processes (AOPs). In this work, CoFe alloy particles encapsulated in nitrogen doped graphitic carbon (donated as CoFe@N-GC), in situ converted from cobalt modified Prussian blue (PB) precursor through a two-step carbonization route, is rationally designed and synthesized as an advanced catalyst for the degradation of antibiotics norfloxacin (NOF) by coupling with peroxymonosulfate (PMS). The resultant hybrid catalyst can not only offer a conductive network that promotes the electron transfer but also protect the metal species from being leached out. By serving as a catalyst/activator, it shows an outperforming performance in catalytic degradation of organic pollutants than other catalysts (i.e. CuO, CoFe 2 O 4 , and biochar). The electron paramagnetic resonance (EPR) results clearly reveal that the sulfate radicals (SO 4 •− ) and singlet oxygen ( 1 O 2 ) are the dominant reactive oxidative species (ROS). After four successive cycles, CoFe@N-GC still performs excellent catalytic activity, leading to a NOF degradation of 94.4% within 20 min ([NOF] = 15 µM, [PMS] = 0.2 mM, [Catalyst] = 0.05 g L −1 , pH = 6.0). This study highlights the in situ synthesis of CoFe@N-GC with outstanding activities for catalytic degradation of organic pollutants.
研究领域:
环境科学
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材料科学
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化学工程
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催化
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水处理
✓ 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）