The Experts below are selected from a list of 3942 Experts worldwide ranked by ideXlab platform
Florent Occelli - One of the best experts on this subject based on the ideXlab platform.
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Sound velocity in Iron Carbide (Fe3c) at high pressure: Implications for the carbon content of the Earth's inner core
Physics of the Earth and Planetary Interiors, 2009Co-Authors: Guillaume Fiquet, James Badro, Eugene Gregoryanz, Yingwei Fei, Florent OccelliAbstract:We measured compressional sound velocities of Fe3c cohenite at high pressure by inelastic X-ray scattering (IXS).We show that Fe3c follows Birch's law for the longitudinal acoustic velocity VP, namely a linear dependence between velocity and density. This dataset completes the previous sets recently established by Badro et al. (2007) for FeO, FeSi, FeS, and FeS2, and provides new mineralogical constraints on the composition of Earth's core. Our results, combined with data already obtained for other Iron alloys, are compared with seismic data. This suggests that a reduced carbon amount in the inner core could reasonably explain density and velocity differences between measurements made on pure Iron and seismic models. This conclusion, however, depends on the remaining uncertainty on magnetic structure for a very low carbon content in the Iron alloy. It does not preclude the incorporation of another light element in the inner core, such as silicon.
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Sound velocity in Iron Carbide (Fe3c) at high pressure: Implications for the carbon content of the Earth's inner core
Physics of the Earth and Planetary Interiors, 2009Co-Authors: Guillaume Fiquet, James Badro, Eugene Gregoryanz, Yingwei Fei, Florent OccelliAbstract:International audienc
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sound velocity in Iron Carbide Fe3c at high pressure implications for the carbon content of the earth s inner core
Physics of the Earth and Planetary Interiors, 2009Co-Authors: Guillaume Fiquet, James Badro, Eugene Gregoryanz, Florent OccelliAbstract:We measured compressional sound velocities of Fe3c cohenite at high pressure by inelastic X-ray scattering (IXS). We show that Fe3c follows Birch’s law for the longitudinal acoustic velocity VP, namely a linear dependence between velocity and density. This dataset completes the previous sets recently established by Badro et al. (2007) for FeO, FeSi, FeS, and FeS2, and provides new mineralogical constraints on the composition of Earth’s core. Our results, combined with data already obtained for other Iron alloys, are compared with seismic data. This suggests that a reduced carbon amount in the inner core could reasonably explain density and velocity differences between measurements made on pure Iron and seismic models. This conclusion, however, depends on the remaining uncertainty on magnetic structure for a very low carbon content in the Iron alloy. It does not preclude the incorporation of another light element in the inner core, such as silicon. © 2008 Published by Elsevier B.V.
Hui Yang - One of the best experts on this subject based on the ideXlab platform.
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Boosting the oxygen reduction performance of MOF-5-derived Fe-N-C electrocatalysts via a dual strategy of cation-exchange and guest-encapsulation
Electrochimica Acta, 2021Co-Authors: Jia-wei Huang, Yu-bin Chen, Hai-bin Zhu, Jin-meng Yang, Hui YangAbstract:Abstract MOF-5 is an excellent self-sacrificed template with fascinating advantages (e.g. thermal robustness, ultrahigh surface area) to prepare highly porous carbon materials for diverse applications but Fe-N-C catalysts derived from MOF-5 seem yet unexplored. Through a dual strategy of cation-exchange and guest-encapsulation, an excellent MOF-5-derived Fe-N-C electrocatalyst toward oxygen reduction reaction was accomplished involving three steps. First, bimetallic Fe/Zn-MOF-5 was obtained by solid-liquid cation exchange between MOF-5 and Fe(BF4)2 solution. Second, infiltration of imidazole molecules into the channels of MOF-5 was achieved via a wet impregnation method, giving the precursor of imidazole@Fe/Zn-MOF-5. Finally, pyrolysis of imidazole@Fe/Zn-MOF-5 under the optimal conditions produced a porous Fe-N-C carbon catalyst decorated by Iron Carbide (Fe3c) nanoparticles, which exhibits a better ORR catalytic performance (E1/2 = 0.86 V vs. RHE) and higher stability than the benchmark Pt/C in the alkaline electrolyte. Application in the homemade primary Zn-air battery as the cathode catalyst also achieves a maximum-power density of 85 mW cm−2, and a satisfactory durability (slight decay by 8.4% in voltage @ 5 mA cm−2 for 70 h). The current work provides a facile and general method to convert MOF-5 into efficient Fe-N-C catalysts with the tunable ORR performance, which may offer more insights into designing highly efficient MOF-derived Fe-N-C electrocatalysts toward ORR.
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Exploring Efficient Fe/N/C Electrocatalysts for Oxygen Reduction from Nonporous Interpenetrated Metal–Organic Framework Involving in Situ Formation of ZnO Templates
ACS Sustainable Chemistry & Engineering, 2020Co-Authors: Jia-wei Huang, Yu-bin Chen, Xiang-lan Chen, Xiao Liu, Yue Zhao, Hai-bin Zhu, Hui YangAbstract:Efficient Fe/N/C electrocatalysts for oxygen reduction reaction (ORR) have been prepared from a nonporous 8-fold interpenetrated metal–organic framework (Fe–Zn-TTPA) bearing dense Zn(II)–carboxylate coordination units. During pyrolysis, the Zn(II)–carboxylate moieties gradually decompose into nanosized zinc oxide (ZnO) particles, serving as thermally removal templates to tune the texture of carbon matrix via carbothermal reduction. With the assistance of in situ formed nanosized ZnO templates, the optimal Fe/N/C electrocatalyst, namely, Fe/N/C-1000-0.05, show well-dispersed ORR-active sites of Iron Carbide (Fe3c) nanoparticles and Fe–Nx species hosted by a hierarchical porous carbon matrix with dominant mesopores. In alkaline electrolyte, a higher ORR activity than the benchmark Pt/C was achieved (Eonset = 0.98 V vs reversible hydrogen electrode (RHE); E1/2 = 0.86 V vs RHE). Moreover, Zn–air battery using Fe/N/C-1000-0.05 as a cathode catalyst exhibits a peak power density of 130 mW cm–2 and outstanding d...
John Wang - One of the best experts on this subject based on the ideXlab platform.
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Flexible and Wearable All-Solid-State Al-Air Battery Based on Iron Carbide Encapsulated in Electrospun Porous Carbon Nanofibers.
ACS applied materials & interfaces, 2018Co-Authors: Afriyanti Sumboja, Wenjie Zang, Shuoyan Yin, Suxi Wang, Stephen J. Pennycook, Zongkui Kou, Zhaolin Liu, John WangAbstract:In this work, electrospinning N-doped carbon nanofibers containing Iron Carbide (Fe3c@N-CFs) are synthesized and employed as the cathode in the flexible Al–air battery. Benefiting from the excellent catalytic activity of the Iron Carbide which is uniformly encapsulated in the N-doped carbon matrix, as well as the large specific surface area of the cross-linked network nanostructure, the as-prepared Fe3c@N-CFs show outstanding catalytic activity and stability toward oxygen reduction reaction. The as-fabricated all-solid-state Al–air batteries with Fe3c@N-CF catalyst show a stable discharge voltage (1.61 V) for 8 h, giving a capacity of 1287.3 mA h g–1.
Guillaume Fiquet - One of the best experts on this subject based on the ideXlab platform.
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Sound velocity in Iron Carbide (Fe3c) at high pressure: Implications for the carbon content of the Earth's inner core
Physics of the Earth and Planetary Interiors, 2009Co-Authors: Guillaume Fiquet, James Badro, Eugene Gregoryanz, Yingwei Fei, Florent OccelliAbstract:We measured compressional sound velocities of Fe3c cohenite at high pressure by inelastic X-ray scattering (IXS).We show that Fe3c follows Birch's law for the longitudinal acoustic velocity VP, namely a linear dependence between velocity and density. This dataset completes the previous sets recently established by Badro et al. (2007) for FeO, FeSi, FeS, and FeS2, and provides new mineralogical constraints on the composition of Earth's core. Our results, combined with data already obtained for other Iron alloys, are compared with seismic data. This suggests that a reduced carbon amount in the inner core could reasonably explain density and velocity differences between measurements made on pure Iron and seismic models. This conclusion, however, depends on the remaining uncertainty on magnetic structure for a very low carbon content in the Iron alloy. It does not preclude the incorporation of another light element in the inner core, such as silicon.
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Sound velocity in Iron Carbide (Fe3c) at high pressure: Implications for the carbon content of the Earth's inner core
Physics of the Earth and Planetary Interiors, 2009Co-Authors: Guillaume Fiquet, James Badro, Eugene Gregoryanz, Yingwei Fei, Florent OccelliAbstract:International audienc
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sound velocity in Iron Carbide Fe3c at high pressure implications for the carbon content of the earth s inner core
Physics of the Earth and Planetary Interiors, 2009Co-Authors: Guillaume Fiquet, James Badro, Eugene Gregoryanz, Florent OccelliAbstract:We measured compressional sound velocities of Fe3c cohenite at high pressure by inelastic X-ray scattering (IXS). We show that Fe3c follows Birch’s law for the longitudinal acoustic velocity VP, namely a linear dependence between velocity and density. This dataset completes the previous sets recently established by Badro et al. (2007) for FeO, FeSi, FeS, and FeS2, and provides new mineralogical constraints on the composition of Earth’s core. Our results, combined with data already obtained for other Iron alloys, are compared with seismic data. This suggests that a reduced carbon amount in the inner core could reasonably explain density and velocity differences between measurements made on pure Iron and seismic models. This conclusion, however, depends on the remaining uncertainty on magnetic structure for a very low carbon content in the Iron alloy. It does not preclude the incorporation of another light element in the inner core, such as silicon. © 2008 Published by Elsevier B.V.
Jia-wei Huang - One of the best experts on this subject based on the ideXlab platform.
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Boosting the oxygen reduction performance of MOF-5-derived Fe-N-C electrocatalysts via a dual strategy of cation-exchange and guest-encapsulation
Electrochimica Acta, 2021Co-Authors: Jia-wei Huang, Yu-bin Chen, Hai-bin Zhu, Jin-meng Yang, Hui YangAbstract:Abstract MOF-5 is an excellent self-sacrificed template with fascinating advantages (e.g. thermal robustness, ultrahigh surface area) to prepare highly porous carbon materials for diverse applications but Fe-N-C catalysts derived from MOF-5 seem yet unexplored. Through a dual strategy of cation-exchange and guest-encapsulation, an excellent MOF-5-derived Fe-N-C electrocatalyst toward oxygen reduction reaction was accomplished involving three steps. First, bimetallic Fe/Zn-MOF-5 was obtained by solid-liquid cation exchange between MOF-5 and Fe(BF4)2 solution. Second, infiltration of imidazole molecules into the channels of MOF-5 was achieved via a wet impregnation method, giving the precursor of imidazole@Fe/Zn-MOF-5. Finally, pyrolysis of imidazole@Fe/Zn-MOF-5 under the optimal conditions produced a porous Fe-N-C carbon catalyst decorated by Iron Carbide (Fe3c) nanoparticles, which exhibits a better ORR catalytic performance (E1/2 = 0.86 V vs. RHE) and higher stability than the benchmark Pt/C in the alkaline electrolyte. Application in the homemade primary Zn-air battery as the cathode catalyst also achieves a maximum-power density of 85 mW cm−2, and a satisfactory durability (slight decay by 8.4% in voltage @ 5 mA cm−2 for 70 h). The current work provides a facile and general method to convert MOF-5 into efficient Fe-N-C catalysts with the tunable ORR performance, which may offer more insights into designing highly efficient MOF-derived Fe-N-C electrocatalysts toward ORR.
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Exploring Efficient Fe/N/C Electrocatalysts for Oxygen Reduction from Nonporous Interpenetrated Metal–Organic Framework Involving in Situ Formation of ZnO Templates
ACS Sustainable Chemistry & Engineering, 2020Co-Authors: Jia-wei Huang, Yu-bin Chen, Xiang-lan Chen, Xiao Liu, Yue Zhao, Hai-bin Zhu, Hui YangAbstract:Efficient Fe/N/C electrocatalysts for oxygen reduction reaction (ORR) have been prepared from a nonporous 8-fold interpenetrated metal–organic framework (Fe–Zn-TTPA) bearing dense Zn(II)–carboxylate coordination units. During pyrolysis, the Zn(II)–carboxylate moieties gradually decompose into nanosized zinc oxide (ZnO) particles, serving as thermally removal templates to tune the texture of carbon matrix via carbothermal reduction. With the assistance of in situ formed nanosized ZnO templates, the optimal Fe/N/C electrocatalyst, namely, Fe/N/C-1000-0.05, show well-dispersed ORR-active sites of Iron Carbide (Fe3c) nanoparticles and Fe–Nx species hosted by a hierarchical porous carbon matrix with dominant mesopores. In alkaline electrolyte, a higher ORR activity than the benchmark Pt/C was achieved (Eonset = 0.98 V vs reversible hydrogen electrode (RHE); E1/2 = 0.86 V vs RHE). Moreover, Zn–air battery using Fe/N/C-1000-0.05 as a cathode catalyst exhibits a peak power density of 130 mW cm–2 and outstanding d...
