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Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization

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Nano-Micro Letters 2025年第1期17卷 281-292页

作者： Xing Wang Wei Pi Sheng Hu Haifeng Bao Na Yao Wei Luo State Key Laboratory of New Textile materials and Advanced Processing Technology Key Laboratory of New Textile Materials and Applications of Hubei ProvinceSchool of Materials Science and EngineeringWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry and Molecular sciences Wuhan UniversityWuhan 430072People’s Republic of China

Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based *** introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in ***,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this *** and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER *** critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.

关键词： NiFe-based catalysts d-orbital coupling Oxygen evolution reaction Anion exchange membrane electrolyzer

Crustal magma oxidation state and endowments in porphyry copper deposits

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Science China earth sciences 2025年第1期 226-236页

作者： Yumin AI Massimo CHIARADIA Chao WU Huayong CHEN Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of sciences Department of earth sciences University of Geneva Guangdong Provincial Key Laboratory of Mineral Physics and materials

Porphyry copper deposits（PCDs） supply the majority of the world's copper（Cu） as well as significant amounts of molybdenum（Mo） and gold（Au）. The formation of these deposits is controlled by a variety of geological factors, among which the magmatic oxidation is one of the focuses of current research. This study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium（V） to scandium（Sc） and its correlation with the oxygen fugacity （fO2） of magmas from arcs of various crustal thicknesses globally. We compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number（Mg#） at the onset of magnetite fractionation is strongly positively correlated with fO2of the equilibrium magma. Based on this,the oxidation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts（materials, display higher oxidation states than most of their thicker crust counterparts. These findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the oxidation state of arc magmas and, consequently, their capacity to generate PCDs. Highly oxidized, primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On the contra

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Synthesis and crystal structure of sodium praseodymium polyphosphate, NaPr(PO_3)_4

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Journal of Rare earths 2009年第1期27卷 1-3页

作者： K.Horchani-Naifer J.Amami M.Férid Research Unit of Rare earth materials National Research Center in Sciences of Materials

Reaction of Na2CO3, Pr6O11 and H3PO4 gave the sodium praseodymium polyphosphate NaPr（PO3）*** title compound crystallized in the monoclinic P21/n space group with a=0.9965（4） nm, b=1.31437（4） nm, c=0.72271（3） nm, β=90.429（3）°, V=0.9465（4） nm3, Z=4, R=0.0493 and wR=0.1266 for 1855 independent *** structure of NaPr（PO3）4 consisted of PrO8 polyhedra sharing oxygen atoms with phosphoric group PO4 to form a three-dimensional framework, delimiting intersecting tunnels in which the sodium ion was *** Na＋ ion was bonded to seven oxygen atoms.

关键词： polyphosphate praseodymium crystal structure infrared spectroscopy rare earths

Fluoride Conversion Coating on Biodegradable AZ31B Magnesium Alloy

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Journal of materials Science & Technology 2014年第7期30卷 666-674页

作者： Tingting Yan Lili Tan Bingchun Zhang Ke Yang Faculty of materials Science and Engineering Kunming University of Science and Technology Institute of Metal Research Chinese Academic of Sciences

A fluoride conversion coating was successfully prepared on AZ31B magnesium alloy by chemical reaction in hydrofluoric acid. Morphologies, composition, bonding strength, corrosion properties, in vitro cytotoxicity and antibacterial properties of the coating were investigated, respectively. The scanning electron microscopy observations revealed a dense coating with some irregular pores. The thin-film X-ray diffraction analysis indicated that the coating was mainly composed of MgO and MgF2. The electrochemical impedance spectroscopy results showed that the fluoride conversion coating significantly improved the corrosion resistance of AZ31B. The hydroxyapatite formed on the surface of the fluoride coated AZ31 B after being immersed in the simulated blood plasma indicated the good bioactivity of the material. The in vitro cytotoxicity test showed that the fluoride coated AZ31B alloy was not toxic to BMMSCs （human bone marrow-derived mesenchymal stem cells）. It was also found that the fluoride coated AZ31 B alloy had antibacterial capability.

关键词： AZ31B magnesium Fluoride coating Corrosion resistance Cytotoxicity Antibacterial

Role of matrix phase and electric field gradient in Na_(1/2)Bi_(1/2)TiO_(3)eBaTiO_(3) :ZnO composites

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Journal of Materiomics 2022年第2期8卷 498-510页

作者： Lalitha Kodumudi Venkataraman Till Fromling Jurgen Rodel Department of materials and earth sciences Technical University of DarmstadtGermany

Na_(1/2)Bi_(1/2)TiO_(3)-based materials exhibit potential for applications in high-power *** com-posites of Na_(1/2)Bi_(1/2) TiO_(3)-yBaTiO_(3)(NBTyBT;y denotes mole%)with ZnO inclusions were demonstrated to stabilize a ferroelectric equilibrium that led to enhanced thermal depolarization temperature(T_(d))and increased mechanical quality factor(Q_(m)).This work addresses the influence of the matrix NBTyBT phase by investigating two limiting choices based on symmetry(tetragonal/rhombohedral)and polar(relaxor/ferroelectric)*** the composites constituting the tetragonal NBT9BT(non-ergodic relaxor at room temperature)matrix phase exhibit improved T d,the critical temperatures in the composites with rhombohedral NBT3BT(displaying spontaneous ferroelectric order at room temperature)exhibit only marginal ***,NBT3BT composites feature a 45%increase in Q m,while the corresponding increase is roughly three-fold for the NBT9BT composites.A 3-D Finite Element Method is used to simulate the electric field gradient at the matrix/inclusion interface,with the effective field distribution estimated to be higher than the applied field for highly conducting ZnO *** electrical properties indicate that,while the deviatoric stress at the matrix/inclusion interface stabilizes the ferroelectric equilibrium for the relaxor matrix phase,the stresses disrupt the long-range order for the ferroelectric matrix *** results establish the volume-limit of the second phase to stabilize a ferroelectric equilibrium,in addition to substantiating the role of residual stress evidenced by changes in the polar ***,a comparison of the composites with different NBTyBT phases is presented,with NBT6BT:ZnO composites demonstrating an optimal increase in both T_(d) and Q_(m).

关键词： Thermal depolarization Na_(1/2)Bi_(1/2)TiO_(3) BaTiO_(3) NBT-Based Lead-free composites Hard-type

Voltage-driven charge-mediated fast 180 degree magnetization switching in nanoheterostructure at room temperature

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npj Computational materials 2017年第1期3卷 137-145页

作者： Min Yi Hongbin Zhang Bai-Xiang Xu Department of materials and earth sciences Technische Universitat Darmstadt64287 DarmstadtGermany

Voltage-driven 180°magnetization switching without electric current provides the possibility for revolutionizing the *** demonstrated the voltage-driven charge-mediated 180°magnetization switching at room temperature by combining firstprinciples calculations and temperature-dependent magnetization dynamics *** electric field(E)-induced interface charge is found to allow a giant modulation of the magnetic anisotropy(K)of the *** K is revealed to vary linearly with respect to E and the epitaxial *** dynamics simulations using the so-obtained K show that both inplane and perpendicular 180°switching can be achieved by E *** temperature effect renders the 180°switching as probability *** analysis indicates a fast(around 4 ns)and low-error-probability 180°switching achievable at room temperature by controlling the magnitude of E and the pulse *** study inspires the rational design of miniaturized nanoscale spintronic devices where thermal fluctuation has a great impact.

关键词： magnetization charge render

BaTiO_(3)solid solutions co-doped with Gd^(3+)and Eu^(3+):Synthesis,structural evolution and dielectric properties

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Journal of Rare earths 2024年第10期42卷 1920-1926页

作者： R.Martínez-López M.Pérez-Labra J.A.Romero-Serrano F.R.Barrientos-Hernández M.Reyes-Pérez M.I.Valenzuela-Carrillo G.Urbano-Reyes V.E.Reyes-Cruz G.I.Dávila-Pulido academic area of earth sciences and materials Autonomous University of Hidalgo StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico Metallurgy and materials Department ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous University of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO_(3)solid solutions codoped with rare earth elements(Gd^(3+)and Eu^(3+))prepared using the solid-state reaction method are *** pure precursor powders of BaCl_3,TiO_(2),Gd_(2)O_(3),and Eu_(2)O_(3)were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 MPa and sintered at 1300℃in air atmosphere for 6 h to obtain Ba_(1-3x)Gd_(2x)Ti_(1-3x)Eu_(4x)O_(3)(x=0,0.0015,0.01 and0.1).X-ray diffraction(XRD)and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO_(3)for the samples with x=0,0.0015 and 0.01,as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd^(3+)and Eu^(3+)in the BaTiO_(3)structure is reached for the sample with x>0.01,and the orthorhombic Eu_2TiO_(5)and monoclinic BaTi_(2)O_(5)secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO_(3)around 716 cm^(-1)(LO of A1 symmetry),515 cm^(-1)(TO of A1 symmetry),and 305 cm^(-1)(B1).The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the BaTiO_(3)*** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO_(3) Doping Gadolinium Europium Synthesis Rare earths

Rare earth upconversion nanophosphors: synthesis, functionalization and application as biolabels and energy transfer donors

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Journal of Rare earths 2010年第6期28卷 807-819页

作者：张超孙聆东张亚文严纯华 Beijing National Laboratory for Molecular sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications PKU-HKU Joint Laboratory on Rare Earth Materials and Bioinorganic Chemistry Peking University

This review focused on rare earth upconversion nanophosphors (UCNPs), a particular class of emitters whose photoluminescence mechanism is of fundamental difference from that of conventional dyes and semiconductor quantum dots. We in the first section gave a brief summary on a variety of synthetic methodologies developed during the past decades. Instead of presenting an exhaustive reference list, we selected only a few representative examples, illustrating the merits and limits of each involved synthetic route. Then we surveyed the recent progress in the functionalization techniques for these nanomaterials, depicting the modification in microstructures and improvement in properties with respect to the parent nanoparticles. And finally, we emphasized their application in the research fields of biolabeling and energy transfer, narrating their superior performance benefiting from the unique excitation and emission properties.

关键词： upconversien nanophosphor biolabel energy transfer rare earths

The final collision of the CAOB:Constraint from the zircon U-Pb dating of the Linxi Formation,Inner Mongolia

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Geoscience Frontiers 2015年第2期6卷 211-225页

作者： Jie Han Jian-Bo Zhou Bin Wang Jia-Lin Cao College of earth sciences Jilin University School of Resources and materials Northeastern University at Qinghuangdao

The Linxi Formation occupies an extensive area in the eastern Inner Mongolia in the Central Asian Orogenic Belt （CAOB）. The Linxi Formation is composed of slate, siltstone, sandstone and plant, lamellibranch microfossils in the associated strata. Major and trace element data （including REE） for sandstones from the formation indicate that these rocks have a greywacke protolith and have been deposited during a strong tectonic activity. LA-ICPMS U-Pb dating of detrital zircons yield ages of 1801 to 238 Ma for four samples from the Linxi Formation. 425-585 Ma, together with the ~500 Ma age for the metamorphism event previously determined for Northeast China, indicates that their provenance is the metamorphic rocks of Pan-African age that have a tectonic affinity to NE China. A few older zircons with U-Pb ages at 1689-1801 Ma, 1307 1414 Ma, 593-978 Ma are also present, revealing the Neoproterozoic history of NE China. The youngest population shows a peak at ca. 252 Ma, suggesting that the main deposition of the Linxi Formation was at late Permain. Moreover, the ca. 250 Ma zircon grains of all four samples yield weighted mean ^206pb/^238U ages of 250 ± 3 Ma, 248 ± 3 Ma, 249 ± 3 Ma, and 250 ± 2 Ma, respectively. These ages, together with the youngest zircon age in the sample ZJB-28 （ca. 238 Ma）, suggest that the deposition of the Linxi Formation extended to the early Triassic. Combining with previous results, we suggest that the final collision of the Central Asian Orogenic Belt （CAOB） in the southern of Linxi Formation, which located in the Solonker-Xra Moron-Changchun suture, and the timing for final collision should be at early Triassic.

关键词： Linxi formation LA-ICPMS U-Pb dating Solonker Xra Moron Changchun suture Final collision timing Early Triassic Central Asian Orogenic Belt