JOURNAL OF POWER SOURCES
·
2023
·
IF 9.2
Yabiao Pei,Weikang Zhu,Runfei Yue,Jie Yao,Xin Liu,Lianqin Wang,Junfeng Zhang,Yan Yin,Michael D. Guiver
Adjusting catalyst/ionomer agglomerate is crucial to a high-performance catalyst layer (CL), particularly for non-precious metal catalysts . As a sacrificial component, the solvent plays a vital role during the CL formation process and resulting microstructure, determining the performance of the anion exchange membrane fuel cells (AEMFCs). Here, solvent mixtures of isopropanol (IPA) and tetrahydrofuran (THF) are studied for the controllable construction of the Co/Fe–N–C CL. The results indicate that the aggregate state of the ionomers and catalysts and the final CL microstructure strongly depend on the ratio of IPA and THF. The CL prepared with IPA: THF = 1:2 (v/v) shows a homogeneous distribution of Co/Fe–N–C catalysts, embedded in the ionomer matrix, due to the fast volatilization and low viscosity of the catalyst ink. The Co/Fe–N–C CL with high moisture adsorption behavior and retention ability results in a high performance AEMFC with peak power density of 545.3 mW cm −2 at 80 °C. The obtained results can guide the rational design of microstructure in non-precious metal CLs for high-performance AEMFCs.
研究领域:
材料科学
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化学工程
·
电化学
·
燃料电池技术
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Hongbin Chen,Zhongye Yu,Weikun Sun,Tao Li,Jian Zhang,Zumin Qiu,Mohammad Younas
In this work, 2LDH-CoFe 2 O 4 @BHC catalyst was prepared by modifying magnetic corncob-based hydrochar (CoFe 2 O 4 @BHC) with Co/Fe layered double hydroxide (Co/Fe-LDH), which was used to activate peroxymonosulfate (PMS) for tetracycline (TC) degradation. 2LDH-CoFe 2 O 4 @BHC demonstrated effective activation of PMS and rapid removal of TC (100 %) within 10 min by leveraging structural modulation and synergistic interactions among multiple components. In contrast, BHC (26.02 %), CoFe 2 O 4 (59.25 %), and CoFe 2 O 4 @BHC (61.88 %) presented poor removal efficiency. Furthermore, it was shown that both the free radicals (SO 4 •- ) and non-free radicals ( 1 O 2 ) were essential in the degradation process, and the catalytic mechanism was revealed to be a synergistic process with the characterization results from in-situ Raman, electrochemical characterization, and X-ray photoelectron spectroscopy (XPS). The catalytic performance of 2LDH-CoFe 2 O 4 @BHC was also evaluated using a self-developed fixed-bed reactor, demonstrating its strong stability and resistance to interference during long-term operation. The potential degradation pathway of TC in the 2LDH-CoFe 2 O 4 @BHC + PMS system was suggested based on the quadrupole time-of-flight mass spectrometry (QTOF/MS) findings. It was found that the toxicity of the intermediates produced by TC degradation significantly reduced. This study presented an insight for the decomposition of organic pollutants by synthetic biochar-loaded catalysts.
研究领域:
环境科学
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化学工程
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材料科学
·
分析化学
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产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2025
·
IF 9.2
Shengxi Zhao,Kaiyu Xie,Ali Reza Kamali
A clean and efficient method for synthesizing Co₃Fe₇ intermetallic is reported, based on the water-asisted molten salt electrolysis employing CoFe₂O₄ electrode, which was fabricated through the thermo-mechanochemical treatment of iron and cobalt oxides. The electrolysis is conducted at the cell voltage of 1.5 V, achiving an energy consumption of 1.47 kWh/kg. Upon formation, the synthesized Co3Fe7 serves as an electrode for catalytic hydrogen production, demonstrating a current density of 91.72 mA/cm2. These performances are compared with those of electrolytic Fe (1.49 kWh/kg, 96.45 mA/cm²) and electrolytic Co (1.30 kWh/kg, 40.76 mA/cm²), both prepared under the same electrolysis potential but with different current-time profiles. The electrolytic Co3Fe7 exhibits superior ferromagnetic properties, with saturation magnetization, remanent magnetization and coercivity values of 157.0 emu/g, 4.3 emu/g and 48.9 Oe, respectively, surpassing values reported in the literature for Fe-Co alloys. The findings suggest a sustainable approach for the green synthesis of Co₃Fe₇ with enhanced ferromagnetic properties. Additionally, the electrolytic Fe and Co₃Fe₇ show promise as electrode materials for molten salt hydrogen production.
研究领域:
材料科学
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电化学
·
能源工程
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产品关联
DOI
高影响因子
ChemSusChem
·
2019
·Vol. 12
·期 19
·4461-4470
·
IF 7.804
Song Yue,Shanshan Wang,Qingze Jiao,Xueting Feng,Kun Zhan,Yiqing Dai,Caihong Feng,Hansheng Li,Tongying Feng,Yun Zhao
Graphical Eggselent electrocatalysts : Yolk–shell Co x Fe 1− x P microspheres are fabricated by phosphidation of cobalt ferrite precursors and used as electrocatalysts for the oxygen evolution reaction (OER). Among the as-prepared Co x Fe 1− x P with various Co/Fe ratios, CoP, FeP, solid CoFeP, cobalt ferrite microspheres, and commercial IrO 2 , Co 0.47 Fe 0.53 P exhibits the best OER performance, including small overpotential, low Tafel slope, and high stability in alkaline medium. The design and development of low-cost, highly efficient, and stable electrocatalysts to take the place of noble-metal catalysts for the oxygen evolution reaction (OER) remain a significant challenge. Herein, the synthesis of yolk–shell-structured binary transition metal phosphide Co x Fe 1− x P with different Co/Fe ratios by phosphidation of a cobalt ferrite precursor is reported. The as-synthesized Co x Fe 1− x P catalysts were used for the OER. All yolk–shell Co x Fe 1− x P catalysts with different Co/Fe ratios showed much better performance than the corresponding solid catalyst. The formation of Co oxides on the catalyst surface during OER and the optimal Co/Fe ratio were found to be critical to their activity. Among the as-prepared Co x Fe 1− x P catalysts, that with a Co/Fe ratio of 0.47/0.53 (Co 0.47 Fe 0.53 P) exhibited the best performance. Co 0.47 Fe 0.53 P has an overpotential of 277 mV at a current density of 10 mA cm −2 , a Tafel slope of 37 mV dec −1 , and superior stability in alkaline medium. The outstanding performance is partly ascribed to the transfer of valence electrons from Co to P and Fe. The Co 0.47 Fe 0.53 P matrix with excellent conductivity and Fe phosphate that is stable on the surface of the catalyst are also helpful for the OER performance. In addition, the yolk–shell structure of Co 0.47 Fe 0.53 P increases the contact area between electrolyte and catalyst. These characteristics of Co 0.47 Fe 0.53 P greatly improve its OER performance. This optimized binary transition metal phosphide provides a new approach for the design of nonprecious-metal electrocatalysts.
研究领域:
材料科学
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电化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF RARE EARTHS
·
2023
·
IF 4.9
Bolang Li,Fei Wang,Kai Li,Ping Ning,Min Chen,Changbin Zhang
The chemical transformation of CO 2 produces carbon compounds that can be used as precursors for the production of chemicals and fuels. Here, we investigated the activity and selectivity of the transition metals (Fe, Co, and Ni) supported on CeO 2 catalyst for CO 2 hydrogenation at atmospheric pressure. We found that Ni/CeO 2 shows the highest CO 2 conversion compared with Fe/CeO 2 and Co/CeO 2 . Besides, Co/CeO 2 and Ni/CeO 2 exhibit nearly 100% CH 4 selectivity while Fe/CeO 2 inclines to produce CO. The characterization results show that the metal-support interaction order is Fe/CeO 2 > Co/CeO 2 > Ni/CeO 2 , the weak metal-support interaction over Ni/CeO 2 benefits the activation of H 2 and then promotes the activity of CO 2 hydrogenation. Additionally, in situ DRIFTS results demonstrate that monodentate formate species rather than bidentate formate are the active intermediates. The main route of CO 2 hydrogenation to CH 4 is that CO 2 is firstly transformed to m-HCOO∗ and then direct hydrogenation of the m-HCOO∗ to CH 4 . This study provides insights into the understanding of the mechanisms of CO 2 hydrogenation on CeO 2 based catalysts.
研究领域:
催化化学
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材料科学
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环境科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 48
·25378-25384
·
IF 8.867
Tanyuan Wang,Chao Wang,Yue Jin,Anna Sviripa,Jiashun Liang,Jiantao Han,Yunhui Huang,Qing Li,Gang Wu
Transition metal phosphides are often studied as hydrogen evolution reaction cathode catalysts, but scarcely as oxygen evolution reaction (OER) anode catalysts for water oxidation. Herein, we report a new amorphous Co0.63Fe0.21P0.16 OER catalyst, which was prepared through a one-step solvothermal process. This catalyst exhibits extraordinary OER catalytic activity in alkaline media and is superior to the state of the art IrO2 in 1.0 M KOH, capable of yielding a current density of 10 mA cm−2 at an overpotential of only 217 mV. This newly achieved high activity outperforms most reported transition metal phosphide catalysts. During the OER, the surface layers of the Co0.63Fe0.21P0.16 nanospheres (200–500 nm) are oxidized, which show the typical Tafel slope of oxides around 40 mV dec−1. The in situ formation of surface Co oxides in the catalysts during the OER along with an optimal doping of Fe are found to be crucial for their remarkable activity. In particular, the metal-rich amorphous phosphide cores, i.e., substrates, probably contribute to OER performance of the catalysts due to their high electrical conductivity. This new type of surface oxidized amorphous transition metal phosphide would provide a new pathway for the design of high-performance OER electrocatalysts.
研究领域:
材料科学
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电化学
·
催化
·
能量转换
·
纳米材料
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DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2023
·Vol. 25
·期 22
·15547-15554
·
IF 3.3
Changyin Zhong,Yifei Yang,Yun Fang,Jun Chen,Bomin Feng,Hongbing Wang,Wenhua Luo,Yunxi Yao
Lanthanum oxide (La2O3) possesses superior reactivity during catalytic hydrogenation, but the intrinsic activity of La2O3 toward H2 adsorption and activation remains unclear. In the present work, we fundamentally investigated hydrogen interaction with Ni-modified La2O3. Hydrogen temperature programmed desorption (H2-TPD) on Ni/La2O3 shows enhanced hydrogen adsorption with a new hydrogen desorption peak at a higher temperature position compared to that on the metallic Ni surfaces. By systematically exploring the desorption experiments, the enhanced H2 adsorption on Ni/La2O3 is due to the oxygen vacancies formed at the metal–oxide interfaces. Hydrogen atoms transfer from Ni surfaces to the oxygen vacancies to form lanthanum oxyhydride species (H–La–O) at the metal–oxide interfaces. The adsorbed hydrogen at the metal–oxide interfaces of Ni/La2O3 results in improved catalytic reactivity in CO2 methanation. Furthermore, the enhanced hydrogen adsorption on the interfacial oxygen vacancies is ubiquitous for La2O3-supported Fe, Co, and Ni nanoparticles. Benefiting from the modification effect of the supported transition metal nanoparticles, the surface oxyhydride species can be formed on La2O3 surfaces, which resembles the recently reported oxyhydride observed on the reducible CeO2 surfaces with abundant surface oxygen vacancies. These findings strengthen our understanding of the surface chemistry of La2O3 and shed new light on the design of highly efficient La2O3-based catalysts with metal–oxide interfaces.
研究领域:
催化
·
表面化学
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材料科学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2026
·
IF 5.9
Huan Song,Le Song,Fangzhou Wu,Yonglei Xing,Xiaoyong Jin,Gang Ni,Xin Wang
Utilizing bimetallic synergy presents a promising approach for creating exceptionally effective catalysts for peroxymonosulfate (PMS) activation. In this study, a Co Fe bimetallic catalyst (Co8Fe1-P1-NC) was constructed by regulating the Co/Fe doping ratio and further introducing phosphorus doping. During PMS activation for phenol (Ph) degradation, Co8Fe1-P1-NC exhibited outstanding catalytic performance. Under the optimized conditions, the Co8Fe1-P1-NC/PMS system achieved complete removal of Ph within 2.5 min, with an apparent rate constant as high as 2.058 min −1 and a total organic carbon (TOC) removal efficiency of up to 80%. Combined results from quenching experiments, electron paramagnetic resonance (EPR), in situ Raman spectroscopy, electrochemical measurements, and premixing tests demonstrated that O 2 •− , 1 O 2 , high-valent metal species, and electron-transfer pathways collectively contributed to Ph degradation. Theoretical calculations indicate that Fe and P doping make the PMS adsorption energy more negative and elongate the O O bond (l O–O ), thereby facilitating PMS activation on the catalyst. Co8Fe1-P1-NC also showed excellent broad-spectrum degradation capability toward various phenolic pollutants, achieving complete removal within 3 min. These findings indicate that the combined regulation of metal active sites and electronic structure through bimetallic synergy and nonmetal doping can significantly enhance PMS activation efficiency, providing a new avenue for the design of high-performance catalysts.
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Fang Liu,Weiyang Jin,Ying Li,Lekai Zheng,Yongchuan Hu,Xuewen Xu,Yanming Xue,Chengchun Tang,Hui Liu,Jun Zhang
The development of efficient non-precious metal catalysts to accelerate the oxygen evolution reaction (OER) kinetics is important for the development of water-derived hydrogen fuel. Iron-cobalt oxide ((Co, Fe) 3 O 4 ) is one of the most promising transition metal-based OER electrocatalysts under alkaline conditions, but its activity is unsatisfactory due to its limited active sites and poor electronic conductivity. Herein, self-supported (Co, Fe) 3 O 4 hierarchical nanosheet arrays with massive oxygen vacancies (denoted as V O -(Co, Fe) 3 O 4 /CC) are synthesized by a simple reduction method at room temperature. Oxygen vacancies can regulate the ratio of Co 2+ /Co 3+ , which leads to the modification of its electronic properties, and it also significantly improves the charge transfer ability and accelerates the reaction. Meanwhile, the unique hierarchical nanosheet arrays structure and abundant oxygen vacancies effectively adjust the number of OER active sites, which has a key role in developing a cost-effective oxygen electrode. Accordingly, V O -(Co, Fe) 3 O 4 /CC exhibits a relatively low overpotential of 286 mV at 10 mA cm −2 and a low Tafel slope of 41 mV dec −1 .
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Fengjiang Chen,Fan Yang,Hongchen Liu,Sai Che,Ge Zhang,Chong Xu,Yongfeng Li
A novel magnetic surface vulcanized cobalt-iron aerogel (CoFe-S MA) with a self-supporting, crosslinked bimetallic nanowire structure was fabricated via NaBH 4 -mediated gelation followed by in-situ vulcanization with Na 2 S solution, which showed efficient sulfadiazine (SDZ) degradation through peroxodisulfate (PDS) activation. The optimized CoFe-0.2S aerogels exhibited the best degradation performance (99.8%) for SDZ (10 mg/L, 100 mL) within 15 min, and the total organic carbon (TOC) removal efficiency reached 53%. The excellent degradation performance was attributed to the accelerated redox process and rapid formation of sulfate radical (SO 4 ·- ) caused by bimetal synergistic effect, as well as the sufficient exposed active sites provided by the self-supporting hierarchical porous structure of the aerogel. Compared with CoFe-MAs, electrochemical impedance spectroscopy (EIS) demonstrated lower resistance and more rapid charge transfer of CoFe-S MAs, which was ascribed to the presence of delocalized electrons in iron sulfides layer. A high turnover frequency (TOF) of 4.0 L∙min −1 ∙g −1 was achieved due to that the reduction effect of S 2- on the surface promoted the regeneration of Fe and Co active species. Electron paramagnetic resonance (EPR) and quenching experiments revealed the dominant reactive oxide species (ROS) to be SO 4 ·- , ‧OH, and Fe (Ⅳ). This work paves the way for the application of metal aerogels in the field of advanced oxidation process based on sulfate radical (AR-AOPs).
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2026
·Vol. 14
·期 5
·124383
·
IF 7.5
Zhengyan Liu,Xiaoli Su,Jie Li,Nan Jiang,Muhammad Imran,Yunxia Chen
A plasma-catalytic system coupled with floating electrode discharge with metal foam-supported catalysts was developed for efficient toluene degradation. The influences of different transition metal oxides (Co, Mn, Ce) loaded onto Fe foam (FF) substrates on the crystal structure, surface morphology and catalytic performance were systematically investigated. Catalysts were symmetrically placed on both sides of the floating electrode. Among the investigated metal oxides, Co was found to form a uniformly distributed CoFe 2 O 4 surface layer on the FF substrate, while Mn and Ce were heterogeneously dispersed as MnO 2 and CeO 2 , respectively. All metal-loaded catalysts enhanced the discharge power of the reactor, attributed to surface charge accumulation on metal oxides. The Co/FF catalyst exhibited the highest toluene degradation efficiency, CO 2 selectivity and O 3 decomposition capability. This plasma-Co/FF system significantly reduced the O 3 concentration from 112 ppm (plasma alone) to 26.2 ppm at a specific input energy (SIE) of 232 J/L. Density functional theory (DFT) calculations suggest that Co sites in CoFe 2 O 4 possess a lower O 3 adsorption energy and higher charge density potential to a higher oxygen vacancy formation tendency, promoting O 3 activation. This study provides an understanding of the mechanistic basis for the rational design of efficient plasma-catalytic systems for toluene removal.
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产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2024
·Vol. 27
·期 1
·133-143
·
IF 9.3
Hongjiao Chen,Kewei Zhang,Yanzhi Xia,Jian Li,Bin Hui
Coupling the urea oxidation reaction (UOR) and hydrogen evolution reaction (HER) in seawater is desirable to produce sustainable and green hydrogen due to the reduced energy consumption. However, developing high-performance UOR/HER electrocatalysts in seawater instead of pure water remains a great challenge. Herein, (B,P,Co,Fe)-Ni anchored on Paulownia Wood (PW) is proposed to enhance the overall urea-(sea)water splitting performance. The resulting sample only needs a potential of 1.34 V to deliver a large current density of 100 mA cm−2 for alkaline UOR and features a remarkable durability to maintain 100 mA cm−2 for 100 h. The HER and UOR (HER||UOR) coupled system in alkaline seawater-urea electrolyte for producing H2 demonstrated a more significantly reduced electrolyzer voltage of 1.67 V obtained at 100 mA cm−2 in comparison to that of the HER||OER system (1.98 V). The well-aligned micro-channels and nanopores in wood frameworks not only improve the hydrophilicity and aerophobicity of the whole electrode, which is conducive to the penetration of the electrolyte and release of bubbles, but also shorten the transmission distance of ions and intermediates to accelerate the reaction kinetic process. Density functional theory calculations reveal that Co, Fe, P and B co-doping in Ni effectively adjusts the electronic structure, and the adsorption/desorption behavior of the urea reaction intermediates is regulated by the synergistic effect from multiple components, resulting in an excellent catalytic activity in seawater-urea media. This work promotes a better understanding of the surface electronic structure modulation of nanowood via doping strategy and offers great potential in the design of advanced UOR/HER catalysts for hydrogen production and urea wastewater treatment.
研究领域:
材料科学
·
电化学
·
环境科学
✓ 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）