JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2021
·Vol. 26
·期 2
·449-456
·
IF 2.647
Liu Shanshan,Li Chenyao,Wang Dongxin,Li Junyi,Yuan Rui,Che Yusi,He Jilin,Song Jianxun
In this research, the reduction mechanism of Nb(V) under various [F − ]/[Nb n+ ] ratios ( α ) was investigated by a series of electrochemical techniques, such as square wave voltammetry (SWV) and chronopotentiometry (CP). We previously studied the electrode reduction process of Nb(V) and revealed that was Nb(V) → Nb(III) → Nb(I) → Nb in NaCl-KCl molten salt. It was found in this research that the electrode reduction process of Nb(V) ion was shortened to Nb(V) → Nb(III) → Nb when α was equal to 1.0; furthermore, the electrode reduction process of Nb(V) ion transforms to Nb(V) → Nb(IV) → Nb when α was greater than or equal to 5.0. Moreover, the reaction mechanism was also discussed in this work. Metallic niobium was collected on a molybdenum electrode under the condition of higher fluoride content after electrolysis in the melt.
研究领域:
材料科学
·
电化学
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高影响因子
ENERGY & FUELS
·
2025
·
IF 5.3
Jiapeng Lu,Chen Yan,Xin Min,Yangai Liu,Ruiyu Mi,Xiaowen Wu,Wei Wang,Zhaohui Huang,Minghao Fang
Nickel-rich layered LiNi0.8Co0.1Mn0.1O2 holds significant potential as a commercially viable cathode material. However, its widespread application is still hindered by inherent challenges, including poor structural stability, cycling performance, and rate capability. This study presents an Nb/Al codoped Li(Ni0.8Co0.1Mn0.1)0.98Nb0.01Al0.01O2 single-crystal ternary cathode material developed to overcome these challenges. The Nb and Al dopants are uniformly distributed throughout the material, resulting in the formation of an α-LiAlO2 protective layer on the surface. This protective layer effectively reduces electrolyte degradation and facilitates Li+ diffusion. Additionally, some of the TM-O bonds are replaced by Nb–O and Al–O bonds, which minimizes the intermixing of Li+ and Ni2+, thus improving the stability of the layered structure. The Nb/Al codoped nickel-rich single-crystal ternary cathode material exhibits superior cycling stability and rate performance compared to the undoped material. After 200 cycles at 1 C within the voltage window of 2.75–4.5 V, the NA-SNCM delivers a specific capacity retention rate of 76.11% (133.65 mA h g–1). Notably, the undoped counterpart displays severe microcracking, whereas the doped samples maintain intact crystallinity.
研究领域:
材料科学
·
电化学
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高影响因子
HYDROMETALLURGY
·
2026
·
IF 6.3
Gengjin Zhang,Yanfang Huang,Longfei Jia,Tianze Chen,Yizhuang Wang,Shengpeng Su,Wenjuan Wang,Hu Sun,Guihong Han
Novel peroxo-complexation strategy was used to purify Nb-rich solution. • NbOF 5 2− transformation to NbO 2 F 5 2− greatly lowers its binding energy with MIBK. • Selectivity coefficient for Sb over Nb was enlarged by over 2300 times. • Nb 2 O 5 product met the high-purity specifications regarding Ta and Sb impurities. The efficient separation of Ta and Sb from Nb in hydrometallurgical processes remains a significant challenge due to their similar chemical behaviors. In this study, a novel peroxo-complexation strategy was introduced to enhance the selectivity of methyl isobutyl ketone (MIBK) extraction in an HF-H 2 SO 4 system. With the addition of H 2 O 2 , the extraction efficiencies of Ta and Sb reached 99.6% and 99.7%, respectively, while the co-extraction of Nb was only 2.32%. The selectivity coefficients of Sb/Nb and Ta/Nb significantly increased from 0.63 and 34.7 to 1461 and 6501, respectively. Stepwise stripping using H 2 SO 4 and pure water effectively recovered Nb and Ta/Sb from the loaded organic phase. Raman spectroscopy and quantum chemical calculations elucidated the mechanism of the enhanced separation selectivity. The peroxo-ligand selectively coordinates with Nb to transform it from NbOF 5 2− to NbO 2 F 5 2− , thereby weakening the negative surface potential of the fluorine atoms bonded to Nb. The binding energy between Nb ions and MIBK decreases from −172 kJ mol −1 to −104 kJ mol −1 , and thus the disparity in the affinity of Nb ions and Ta/Sb ions for MIBK is magnified. Overall, this peroxo-coordination approach provides an efficient and simple pathway for the effective purification of Nb solutions. Download: Download high-res image (176KB) Download: Download full-size image
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高影响因子
Journal of Energy Storage
·
2026
·
IF 10.7
Junming Han,Chunbo Guo,Fangyu Hao,Zihao Cai,Hao Zheng,Zeyi Jiang,Nien-Chu Lai
A high-purity Li 3 InCl 6 electrolyte is synthesized via a facile room-temperature liquid-phase method. • Nb 5+ doping induces lattice distortion and increases lithium vacancy concentration. • The Nb-Doped electrolyte achieves a high ionic conductivity and excellent electrochemical stability. • The assembled all-solid-state lithium battery delivers superior rate capability and long cycling life. Halide solid electrolytes hold great promise for all-solid-state lithium batteries (ASSLBs), yet achieving fast Li + transport and high electrochemical stability through scalable synthesis remains challenging. Herein, we report a facile wet-chemical route to synthesize Nb-doped Li 3 InCl 6 solid electrolytes, where a stepwise slow drying and thermal treatment protocol is adopted to regulate crystallization kinetics. By optimizing the solvent and dopant concentration, the 10% Nb-substituted sample (LIC Nb 1 ) prepared in ethanol shows optimal performance. Structural refinement and spectroscopic analysis reveal that aliovalent Nb 5+ creates Li vacancies and optimizes local lattice environments, promoting fast Li + conduction. Accordingly, LIC-Nb 1 exhibits a room-temperature ionic conductivity of 0.95 mS cm −1 , more than twice that of pristine LIC(Et) (0.44 mS cm −1 ), with a lower activation energy of 0.31 eV and enhanced electrochemical stability. ASSLBs based on LIC-Nb 1 delivers substantially improved rate capability and cycling stability relative to pristine LIC-based cells. At 30 °C, the LIC-Nb 1 -based cell shows stable charge/discharge behavior over 2–4.4 V (vs. Li/Li + ), affording an initial discharge capacity of 182.4 mAh g −1 , and an initial Coulombic efficiency of 91.02%. Under the more demanding rate and prolonged cycling evaluations conducted at 60 °C, the capacity retention of LIC-Nb 1 -based cell after 30 cycles at 0.1C under 100% depth of discharge reaches 83.5%, compared with 66.8% for the LIC(Et)-based counterpart. This work systematically clarifies the solvent effect on the crystal structure and ionic conductivity of LIC electrolytes, proposes a crystallization kinetics modulation strategy to eliminate structural defects, and validates the practical application potential of Nb-doped LIC electrolytes in high-voltage ASSLBs. These findings highlight the integrated strategy of kinetic regulation and heteroatom doping as an effective strategy for engineering high-performance halide solid electrolytes toward advanced all-solid-state lithium batteries. Download: Download high-res image (226KB) Download: Download full-size image
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高影响因子
Molecular Catalysis
·
2026
·
IF 4.3
Dandan Zuo,Wuyu Wang,Miaojia Song,Peng Zheng,Sa Li,Qi Zhang,Xinghua Zhang,Longlong Ma
A ternary Cu-Nb/Al-MCM-41 catalyst achieves 99.60 % 2-methylfuran selectivity at 160 °C under atmospheric H2. • Al incorporation enhances metal dispersion and generates balanced Brønsted-Lewis acidity for controlled C O hydrogenolysis. • Nb promotion enables efficient H2 activation and strengthens Cu-Nb interfacial electronic coupling. • The catalyst exhibits excellent long-term stability and can operate continuously in a fixed bed for 500 h. The selective hydrodeoxygenation (HDO) of furfural (FAL) into 2-methylfuran (2-MF) is a crucial transformation for upgrading lignocellulosic biomass into liquid fuels. Herein, a series of Cu-Nb catalysts supported on mesoporous MCM-41 were developed. Over the optimized Cu-Nb/Al-MCM-41 catalyst, FAL was completely converted and the selectivity of 2-MF was 99.60 % at only 160 °C under ambient hydrogen pressure. Structural analyses revealed that Al incorporation reinforced metal-support interactions, enhanced Cu dispersion, and producing moderate Brønsted-Lewis acid sites, which synergistically facilitated hydrogen transfer and selective C O bond cleavage. In situ DRIFTS and XPS measurements confirmed a tandem hydrogenation-dehydration pathway proceeding via furfuryl-alcohol (FOL) intermediates, where Nb promoted H 2 activation and Al-derived acid centers accelerated dehydration at interfacial Cu-Nb-Al sites. The catalyst maintained high activity and selectivity during 500 h time-on-stream in a fixed-bed reactor, although slight deactivation was observed after prolonged operation. These findings establish a clear structure-function correlation between electronic modulation and acid-metal synergy, offering a sustainable strategy for efficiently producing furan-based biofuels under mild conditions. Download: Download high-res image (291KB) Download: Download full-size image
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高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2026
·Vol. 109
·期 6
·e70904
·
IF 4.2
Xinzi Zhong,Quanneng Zhang,Ji Zou,Keyu Gong,Zhipeng Zhang,Jingjing Liu,Huayue Liang,Shuaihang Qiu,Weimin Wang,Zhengyi Fu
Multicomponent oxide ceramics yield great promises in next-generation thermal protection systems according to their high potential for thermal stability and ablation resistance, but their protective mechanisms remain unclear. In this study, the five multicomponent A 6 B 2 O 17 (A = Zr, Hf; B = Nb, Ta) oxide ceramics with different atomic concentrations, respectively, at A- and B-sites, were prepared via a solid-state reaction with a rapid cooling process. Their phase, structural evolutions, and the properties under high-temperature treatment and dynamic ablations were investigated to reveal thermal stability and anti-ablation mechanisms. Only the (Hf 1/2 Zr 1/2 ) 6 (Ta 1/2 Nb 1/2 ) 2 O 17 with equal molar ratio both at A- and B-sites maintained the A 6 B 2 O 17 phase after heat treatment at 1773 K for 25 h; the other samples underwent phase separation behaviors. In addition, the (Hf 3/4 Zr 1/4 ) 6 (Ta 2/3 Nb 1/3 ) 2 O 17 ceramic showed excellent ablation resistance (∼2500 K, 100 s) with the thinnest oxide layer. This property is attributed to the formation of “skeleton-filler phase” protective composite layer, as the (Zr, Hf)O 2 “skeleton” owns high melting point and low volatility to resist thermal gas erosion, and the A n B 2 O 2n+5 family fills defects and hinders the penetrations of O 2 . This study expects to offer design for advanced thermal barriers suitable for the next-generation hypersonic vehicles and reusable spacecraft.
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Huicai Xie,Quanyi Liu,Xiaohua Luo,Shengcan Ma,Xinqiang Gao,Zhenxing Li,Zhaojun Mo,Jun Shen
For more practical applications, research on magnetic refrigeration has been gradually focused on developing refrigerants with large magnetocaloric effect (MCE) under low magnetic fields (≤2 T). EuTiO 3 exhibits considerable low-field MCE near ordering temperature, meanwhile the magnetic switch from antiferromagnetic to ferromagnetic (AFM-FM) in it provides the feasibility of improving the magnetocaloric performance. In this study, a series of Eu(Ti,Nb,M)O 3 (M=Cu or Zn) compounds were synthesized, and the crystal structure, magnetic properties together with cryogenic MCEs were investigated in detail. The co-substitution contributes to an FM coupling domination in all the compounds. Besides, significantly enhanced and giant low-field MCEs were detected in these compounds. Under the field change of 1 T, all the samples possess remarkable magnetic entropy change (>15 J·kg -1 ·K -1 ) around 5 K without hysteresis. The corresponding refrigerating capacities are calculated to be 68.0, 72.6, 76.0, and 69.6 J·kg -1 , respectively, exhibiting an increase of 149–178% than EuTiO 3 . The outstanding magnetocaloric performances make the Eu(Ti,Nb,M)O 3 (M=Cu or Zn) compounds competitive candidates for cryogenic magnetic refrigeration.
研究领域:
材料科学
·
凝聚态物理
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功能材料
·
低温工程
·
磁学
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DOI
高影响因子
IONICS
·
2026
·
IF 2.6
Yang Hao,Guo Jianling,Xue Juanjuan,Zhang Jingpeng,Liang Guangchuan,Wang Yong
This study successfully prepared high-density LiFePO 4 /C composite materials using a ternary co-doping strategy of Nb 2 O 5 , TiO 2 , and V 2 O 5 , combined with particle size optimization and control techniques. The substitution of Nb⁵⁺ for Li⁺ positions can widen the diffusion channels for Li⁺ and enhance its diffusion kinetics. The replacement of Fe²⁺ by Ti⁴⁺ can stabilize the crystal structure, reduce volume changes during charge-discharge processes, and improve cycling stability. The substitution of Fe²⁺ by V 4⁺ and the introduction of electron defects can increase electronic conductivity. The synergistic co-doping of Nb⁵⁺, Ti⁴⁺, and V 4⁺ increased the electrical conductivity of the LFP material from 2.0 × 10 − 1 to 2.6 × 10 − 1 S cm − 1 and the Li⁺ diffusion coefficient from 7.65 × 10 − 13 to 2.39 × 10 − 12 cm 2 s − 1 . Moreover, by optimizing the particle size distribution and adopting a non-uniform particle grading strategy, small particles can efficiently fill the gaps between large particles, reducing porosity and further increasing the compaction density. The final Li₀.₉₉₀Nb₀.₀₁₀Fe₀.₉₉₀Ti₀.₀₀₅V₀.₀₀₅PO₄ material achieved an industry-leading compaction density of 2.72 g cm − 3 under a pressure of 226 MPa. Electrochemical tests showed that the discharge capacities at 0.2 C and 5 C rates were 166.2 mAh g − 1 and 142.4 mAh g − 1 , respectively, and the capacity retention rate after 1000 cycles at 5 C was 91.34%. The assembled 14,500 cylindrical battery exhibited excellent volumetric energy density (0.2 C: 1166.27 Wh L − 1 , 1 C: 1109.62 Wh L − 1 ). This research provides an effective material design strategy for the development of high-energy-density lithium iron phosphate batteries.
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高影响因子
CHEMICAL PHYSICS LETTERS
·
2021
·
IF 2.328
Zhiling Guo,Shanshan Wu,Deping Xiong,Yefeng Feng,Jin Ke,Kaidan Wu,Yukun Sun,Miao He,Zuyong Feng
A novel ternary SnO 2 -Nb-C composite, which consists of SnO 2 nanoparticles and a fraction of Niobium (Nb) embedded in flake carbon, is synthesized by hydrothermal and ball milling method. To be used as an anode material for lithium-ion batteries (LIBs), the SnO 2 -Nb-C composite is smoothly doped with n-type elements owing to the various valences of Nb , which enhances the electronic conductivity of the electrode, and effectively inhibits volume changes in SnO 2 during the cycle process, thus improving the electrode’s electrochemical performance. Therefore, at 0.2 A g −1 , the capacity is 956 mAh g −1 after 100 cycles, and the rate capacity is 1130.2 mAh g −1 . Furthermore, at 1.0 A g −1 , the specific discharge capacity is 1077.0 mAh g −1 after 500 cycles. According to the characterization results, the SnO 2 -Nb-C nanocomposite can be regarded as a potential anode material for LIBs.
研究领域:
材料科学
·
储能
·
电化学
·
纳米复合材料
·
电池技术
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DOI
高影响因子
ChemSusChem
·
2025
·
IF 6.6
Danfeng Zhang,Jiaxiu Sun,Zhiqi Ren,Yuhang Wang,Zongsheng Qiu,Jianwen Yang,Yongbin He,Meng Qin,Fei Sun,Lianming Zhang,Bin Huang,Yanwei Li,Shunhua Xiao
The application of LiFe 1− y Mn y PO 4 (0 < y < 1) cathode materials with high voltage and high specific energy for lithium-ion batteries is restrained by capacity decay, structure degradation, and low Li + /electronic conductivity, especially at high temperature. In this study, the Nb 5+ -doped olivine-structured LiFe 0.5 Mn 0.5− x Nb x PO 4 (LFMP- x Nb, x = 0%, 0.5%, 1%, 2%, and 3%) are synthesized and characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, and electrochemical techniques. The lattice parameters ( a , b , c , and V ), P O and TM O bond lengths, and particle size are reduced with Nb doping, and the structure stability, electronic/Li + transport rate, and electrochemical performances are improved. The preferred LFMP-1%Nb sample delivers an initial discharge specific capacity of 160.57 mAh g −1 at 0.1 C with a coulombic efficiency of 91.38%, and a specific capacity of 91.23 mAh g −1 at 10 C, and a capacity retention rate of 78.71% with a residual capacity of 106.10 mAh g −1 after 1000 cycles at 1 C. Especially at 55 °C temperature, it can give a discharge specific capacity of 142.9 mAh g −1 and a capacity retention rate of 73.14% after 1000 cycles at 1 C. Graphical Nb 5+ doping shortens the TM O and P O bond lengths, suppressing the Jahn–Teller aberration and the solvation of Mn 2+ ions. Consequently, after 1000 charge-discharge cycles at 1 C rate under 25 °C and 55 o C temperatures, the LiFe 0.5 Mn 0.49 PO 4 −1%Nb cathode material exhibits capacity retention rates of 78.71% and 73.14%, respectively.
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DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·Vol. 52
·期 1
·114-121
·
IF 5.6
Shixian Xie,Pengbo Fu,Lichen Wang,Huayang Gong,Fang Wang,Fenghua Chen,Zhigang Sun,Jiaguo Fan,Yan Zhang,Jian Zhang,Baogen Shen
M-type strontium ferrite (SrFe 12 O 19 ) is widely used in various fields due to its low cost and excellent stability. However, its relatively low saturation magnetization ( M s ) significantly restricts its broader applications. Enhancing M s through non-rare-earth doping via the solid-state reaction method is of significant practical importance. The primary challenge lies in simultaneously maintaining lattice stability and regulating Fe 3+ spin alignment through doping. In this study, a series of non-rare-earth Nb–Zn co-doped SrFe 12- x (Nb a Zn b ) x O 19 ( a : b = 1:1, a : b = 4:5, x = 0.1–0.5) were synthesized using the solid-state reaction method. XRD phase analysis indicated that a single M-type strontium ferrite phase was obtained at the stoichiometric doped ( a:b = 1:1). In contrast, for the non-stoichiometric doped ( a:b = 4:5), a trace amount of the secondary phase SrNb 0.5 Fe 0.5 O 3 was detected in Nb–Zn doped samples with x ≥ 0.2. M s of both stoichiometric and non-stoichiometric doped samples increased within the range of 0≤ x ≤ 0.3 but gradually decreased when x exceeded 0.3. Notably, for the composition with a : b = 4:5, M s reached a maximum value of 79.33 emu/g at x = 0.3, accompanied by a synchronous enhancement of 18.5 % in coercivity ( H c ). Raman spectroscopy analysis revealed the enhancement mechanism of M s : the synergistic occupation of Nb 5+ and Zn 2+ ions. Specifically, Zn 2+ preferentially occupies the 4f 1 tetrahedral sites, while Nb 5+ incorporates into the 4f 2 sites. This co-substitution effectively replaces the spin-down Fe 3+ ions, leading to a significant increase in M s . The presence of a trace amount of the secondary phase SrNb 0.5 Fe 0.5 O 3 in the non-stoichiometrically doped samples, effectively inhibited grain growth, thereby contributing to the enhancement of H c . This study successfully synthesized non-rare-earth-doped strontium ferrite materials via a solid-state reaction method, achieving a significant enhancement in M s . Furthermore, the underlying mechanism for the improvement in M s through Nb–Zn co-doping was elucidated for the first time. Our findings are of significance for the development of high-performance, cost-effective ferrite materials.
研究领域:
材料科学
·
磁学与磁性材料
·
固态化学
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高影响因子
Advanced Optical Materials
·
2025
·Vol. 13
·期 26
·e01335
·
IF 7.2
Xihui Shan,Xulong Lv,Dongxun Chen,Yi Zhang,Lipeng Huang,Yanjie Liang
Multifunctional phosphors combining persistent luminescent and photochromic properties have garnered increasing attention, given their capability of absorbing the photon energy and trapping the light-generated charge carriers by defects. To date, extensive efforts have been devoted to achieving reversible photochromism in visible/infrared afterglow materials. However, research on integrating ultraviolet (UV) persistent luminescence and photochromic behavior into a single material is relatively lacking. Herein, multimode luminescence in a Gd 3+ single-doped Sr 3 (PO 4 ) 2 phosphor is demonstrated, featuring narrowband ultraviolet-B (NB-UVB) photoluminescence, NB-UVB afterglow, and multicolor photochromism. The temperature-dependent NB-UVB photoluminescence of the Sr 3 (PO 4 ) 2 :Gd 3+ phosphor reveals its potential as a ratiometric optical thermometer with high relative sensitivity (2.5% K −1 at 110 K). Meanwhile, this phosphor exhibits robust NB-UVB persistent luminescence lasting >24 h upon X-ray irradiation. Besides, the material also displays exceptional concentration-dependent multicolor photochromism (white-to-blue and white-to-brown) under bright-field conditions only in response to X-ray irradiation, coupled with excellent bleaching and recovery capability under thermal treatment or 254 nm UV light stimulation. The synergistic integration of NB-UVB persistent luminescence and concentration-dependent multicolor photochromism positions this phosphor as a promising candidate for versatile applications, including covert optical tagging, optical information storage, and advanced anti-counterfeiting.
研究领域:
材料科学
·
发光材料
·
光学功能材料
·
光致变色材料
·
持久发光
·
光学测温
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DOI
高影响因子