Solid State Ionics最新文献_第10页

Structure and electrochemical properties of MgAl co-doped spinel LiMn2O4 cathode material MgAl共掺尖晶石LiMn2O4正极材料的结构与电化学性能

IF 3.3 4区材料科学 Q3 CHEMISTRY, PHYSICAL

Solid State Ionics

Pub Date : 2025-11-01 Epub Date: 2025-09-25 DOI: 10.1016/j.ssi.2025.117031

Yongsheng Yang PhD, Long Shi, Junming Guo

MgAl co-doping and single-crystal truncated octahedral morphology strategy was employed to suppress and mitigate the Jahn-Teller distortion and Mn dissolution in spinel-type LiMn₂O₄ materials. LiMg_0.10Al_yMn_1.90-yO₄ (y = 0.03, 0.05, 0.08, 0.10, and 0.12) cathode materials were synthesized via solid-phase combustion method and the effects of varying Al contents on the crystal structures, single-crystal truncated octahedral morphology, valence states of doped elements, rate and long-cycle electrochemical performance, and Li⁺ ion migration kinetics of spinel-type LiMn₂O₄ materials were investigated. The results indicate that MgAl co-doping promotes the crystalline development of spinel-type LiMn₂O₄ material and the preferential growth of {111}, {100}, and {110} crystal planes, forming complete single-crystal truncated octahedral morphology. Among samples with different Mg and Al doping levels, the MgAl co-doped sample LiMg_0.10Al_0.05Mn_1.85O₄ exhibits superior capacity and cycle stability. At a low rate of 1C, the initial discharge specific capacity is 114.7 mAh·g⁻¹, with an 93.6 % capacity retention after 200 cycles; at high rates of 10, 15, and 20C, the initial discharge specific capacities are 94.4, 92.4, and 84.5 mAh·g⁻¹ respectively, with capacity retention rates of 84.1 %, 76.9.2 %, and 81.7 % after 1000 cycles; at high temperatures of 55 °C and rates of 1C, 5C and 10C, the initial discharge specific capacities are 113.7, 111.1 and 100.5 mAh·g⁻¹ respectively, with retention rates of 68.6 %, 46.1 % and 37.8 % after 200, and 500 cycles. The LiMg_0.10Al_0.05Mn₁₈₅O₄ sample has the lowest charge transfer resistance (168.6 Ω) and apparent activation energy (32.39 kJ·mol⁻¹), and the highest Li⁺ diffusion coefficient (1.20 × 10⁻¹¹ cm²·s⁻¹). This indicates that during charging and discharging, Li⁺ ions in this sample encounter lower resistance and energy barriers, resulting in faster migration rates, which can enhance the material's rate capacity and cycling stability.

采用MgAl共掺杂和单晶截断八面体形貌策略抑制和减轻尖晶石型LiMn2O4材料中的Jahn-Teller畸变和Mn溶解。采用固相燃烧法合成了LiMg0.10AlyMn1.90-yO4 （y = 0.03, 0.05, 0.08, 0.10, 0.12）正极材料，研究了Al含量对尖晶石型LiMn2O4材料的晶体结构、单晶截断八面体形态、掺杂元素价态、速率和长周期电化学性能以及Li+离子迁移动力学的影响。结果表明：MgAl共掺杂促进了尖晶石型LiMn2O4材料的结晶发育，{111}、{100}和{110}晶面优先生长，形成完整的单晶截断八面体形貌；在不同Mg和Al掺杂水平的样品中，MgAl共掺杂样品LiMg0.10Al0.05Mn1.85O4表现出优异的容量和循环稳定性。在低倍率1C下，初始放电比容量为114.7 mAh·g−1,200次循环后容量保持率为93.6%；在10、15和20℃高倍率下，初始放电比容量分别为94.4、92.4和84.5 mAh·g−1,1000次循环后容量保持率分别为84.1%、76.9.2%和81.7%；在55°C高温和1C、5C和10C倍率下，电池的初始放电比容量分别为113.7、111.1和100.5 mAh·g−1，循环200次和500次后的保留率分别为68.6%、46.1%和37.8%。LiMg0.10Al0.05Mn185O4样品的电荷转移电阻最低（168.6 Ω），表观活化能最低（32.39 kJ·mol−1），Li+扩散系数最高（1.20 × 10−11 cm2·s−1）。这说明在充放电过程中，该样品中的Li+离子遇到更低的电阻和能量势垒，迁移速度更快，可以增强材料的倍率容量和循环稳定性。

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引用次数: 0

Exploring the structural and conductivity behaviours of mechanochemically and hydrothermally synthesized Ce3+-doped BaSnF4 solid electrolytes for all-solid-state fluoride-ion batteries 机械化学和水热合成Ce3+掺杂BaSnF4全固态氟离子电池固体电解质的结构和导电性研究

IF 3.3 4区材料科学 Q3 CHEMISTRY, PHYSICAL

Solid State Ionics

Pub Date : 2025-11-01 Epub Date: 2025-09-23 DOI: 10.1016/j.ssi.2025.117032

K. Ramakrushna Achary , Sumit Khatua , Kshatri Durga Lalitha Bai , Guruprasad Sahoo , L.N. Patro

Recent studies on batteries have drawn significant attention to all-solid-state fluoride-ion batteries (FIBs) as potential alternatives to the conventional Li-ion batteries because of their higher theoretical energy densities. On the solid electrolyte side, efforts are being made to develop a suitable material with improved ionic conductivity (∼ 10⁻³ S/cm) and enhanced electrochemical stability. SnF₂-based solid electrolyte, BaSnF₄ crystallizes in the PbSnF₄ structure and is frequently considered as a potential solid electrolyte for FIBs operating at room temperature (RT). In this study, the conductivity results of BaSnF₄ are influenced by doping with rare-earth ions (Ce³⁺) at different concentrations and by the synthesis methodology. The structural and transport behaviours of Ce³⁺-doped BaSnF₄ solid electrolytes, prepared by mechanical milling and hydrothermal methods, are compared. The formation of the doped materials, which exhibit a tetragonal phase, is confirmed by X-ray diffraction. The presence of Ce³⁺ in the doped materials prepared by both methods is confirmed by their photoluminescence characteristics. Among the materials investigated in this study, 2 mol% Ce³⁺-doped BaSnF₄, prepared by mechanical milling (Ba_0.98Ce_0.02SnF_4.02-MM) exhibits the highest ionic conductivity and electrochemical stability. The conductivity (RT) exhibited by Ba_0.98Ce_0.02SnF_4.02-MM is higher compared to earlier reports on different rare-earth ion-doped BaSnF₄, which were primarily prepared by solution-based methods. Ion transport number measurement using dc polarization technique revealed that the conductivity exhibited by Ba_0.98Ce_0.02SnF_4.02-MM is mainly due to ionic conduction. The observation of a higher ionic conductivity value in Ba_0.98Ce_0.02SnF_4.02-MM highlights its great potential for use as a solid electrolyte in the fabrication of FIBs.

全固态氟离子电池（FIBs）具有较高的理论能量密度，是传统锂离子电池的潜在替代品，近年来的电池研究引起了人们的极大关注。在固体电解质方面，人们正在努力开发一种合适的材料，该材料具有改善的离子电导率（~ 10−3 S/cm）和增强的电化学稳定性。基于snf2的固体电解质，BaSnF4以PbSnF4结构结晶，经常被认为是在室温（RT）下工作的fib的潜在固体电解质。在本研究中，掺杂不同浓度的稀土离子（Ce3+）和合成方法对BaSnF4的电导率结果产生了影响。比较了机械研磨法和水热法制备的Ce3+掺杂BaSnF4固体电解质的结构和输运行为。x射线衍射证实了掺杂材料的形成，其表现为四方相。两种方法制备的掺杂材料的光致发光特性证实了Ce3+的存在。在所研究的材料中，机械铣削法制备的2 mol% Ce3+掺杂BaSnF4 （Ba0.98Ce0.02SnF4.02-MM）具有最高的离子电导率和电化学稳定性。与先前报道的不同稀土离子掺杂BaSnF4相比，Ba0.98Ce0.02SnF4.02-MM的电导率（RT）更高，主要是通过溶液法制备的。利用直流极化技术测量离子输运数，发现Ba0.98Ce0.02SnF4.02-MM的电导率主要是离子传导。在Ba0.98Ce0.02SnF4.02-MM中观察到较高的离子电导率值，突出了其作为固体电解质在FIBs制造中的巨大潜力。

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引用次数: 0

Thin-film X-ray diffractometry for evaluating effect of BaCO3 coating on the electrolyte of protonic ceramic fuel cells 用薄膜x射线衍射法评价BaCO3涂层对质子陶瓷燃料电池电解质的影响

IF 3.3 4区材料科学 Q3 CHEMISTRY, PHYSICAL

Solid State Ionics

Pub Date : 2025-11-01 Epub Date: 2025-09-27 DOI: 10.1016/j.ssi.2025.117030

Katsuhiro Nomura, Hiroyuki Shimada, Yuki Yamaguchi, Masaya Fujioka, Hirofumi Sumi, Yasunobu Mizutani

The manufacturing of protonic ceramic fuel cells (PCFCs) involves high-temperature sintering at ∼1500 °C to form a dense electrolyte film. This process results in Ba evaporation, which complicates the control of the electrolyte surface composition. To address this problem, we herein examined the effect of modifying the electrolyte (Ba_0.97Zr_0.8Yb_0.2O_3−δ, BZYb20d) surface in anode-supported PCFCs by BaCO₃ slurry coating followed by firing at 1300 °C. X-ray diffractometry (θ–2θ measurements) indicated a decrease in the amount of Yb₂O₃ precipitated on the surface of the thus treated BZYb20d, and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy revealed a decrease in the segregation of Yb₂O₃ at the treated electrolyte surface. Thin-film X-ray diffractometry (ω–2θ measurement) revealed a change in the lattice constant of the BZYb20d electrolyte (thickness = 10 μm) in a BZYb20d/NiO-BZYb20d half-cell as a function of the X-ray penetration depth from the surface to the bulk (i.e., near the BZYb20d/NiO-BZYb20d interface) at 25–900 °C in air, dry N₂, and wet N₂. At 900 °C, the lattice constant of BZYb20d after the BaCO₃ treatment hardly changed upon going from the surface to the bulk, which suggested that the Ba content at the BZYb20d electrolyte surface was almost the same as that in the bulk. The thermal expansion coefficients and chemical expansion rates of the BZYb20d film electrolyte bulk were lower (∼0.66 and ∼ 0.33 times, respectively) than those of BaZr_0.8Y_0.2O_2.9 and BaZr_0.8Yb_0.2O_3−δ bulk. The BaCO₃ treatment increased the maximum power density of the corresponding PCFC from ∼0.5 to ∼0.6 W cm⁻². The cathode fabricated using the modified BZYb20d electrolyte showed a lower polarization resistance (0.07 Ω cm²) than that based on the unmodified electrolyte (0.22 Ω cm²). The Ba deficiency of the BZYb20d electrolyte surface that developed during high-temperature sintering was alleviated by the BaCO₃ coating, and the interfacial resistance between the air electrode and electrolyte therefore decreased.

质子陶瓷燃料电池（pcfc）的制造需要在~ 1500°C的高温烧结以形成致密的电解质膜。这一过程导致Ba蒸发，使电解液表面成分的控制变得复杂。为了解决这一问题，我们研究了BaCO3浆液涂层在1300℃烧制后对阳极负载型pcfc的电解质（Ba0.97Zr0.8Yb0.2O3−δ, BZYb20d）表面进行改性的效果。x射线衍射（θ-2θ测量）表明，处理后的BZYb20d表面的Yb2O3析出量减少，扫描电镜和能量色散x射线能谱分析表明，处理后的电解质表面的Yb2O3偏析减少。薄膜x射线衍射（ω-2θ测量）揭示了在25-900℃空气、干N2和湿N2条件下，BZYb20d/NiO-BZYb20d半电池中BZYb20d电解质（厚度= 10 μm）的晶格常数随x射线从表面到本体（即BZYb20d/NiO-BZYb20d界面附近）的穿透深度的变化。在900℃时，经过BaCO3处理的BZYb20d从表面到体块的晶格常数几乎没有变化，说明BZYb20d电解质表面的Ba含量与体块中的Ba含量基本相同。BZYb20d薄膜电解质体的热膨胀系数和化学膨胀率分别为BaZr0.8Y0.2O2.9和BaZr0.8Yb0.2O3−δ体的约0.66倍和约0.33倍。BaCO3处理使相应PCFC的最大功率密度从~ 0.5增加到~ 0.6 W cm−2。用改性BZYb20d电解液制备的阴极极化电阻（0.07 Ω cm2）比未改性电解液制备的阴极极化电阻（0.22 Ω cm2）低。BZYb20d电解质表面在高温烧结过程中产生的Ba缺乏症通过BaCO3涂层得到缓解，从而降低了空气电极与电解质之间的界面阻力。

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引用次数: 0

Hydration and conduction behavior of Sc and Zr-substituted Ba7Nb4MoO20 Sc和zr取代Ba7Nb4MoO20的水化和导电行为

IF 3.3 4区材料科学 Q3 CHEMISTRY, PHYSICAL

Solid State Ionics

Pub Date : 2025-11-01 Epub Date: 2025-09-16 DOI: 10.1016/j.ssi.2025.117027

Sara Adeeba Ismail , Lulu Jiang , Hui Guo , Wenhao Li , Donglin Han

Ba₇Nb₄MoO₂₀ has acceptably high ionic conductivity at 600–800 °C and is attractive for potential application in high temperature solid state electrochemical devices. Up to now, most of the research focuses on isovalent and donor-doping to improve the electrical properties of Ba₇Nb₄MoO₂₀. In this work, an acceptor-doping strategy was taken by doping Sc and Zr to partially substitute Nb. More vacant oxygen sites thereby form for charge compensation, leading to the increasing proton concentration following the compositional sequence of hydrated Ba₇Nb₄MoO₂₀ < Ba₇Nb_3.97Zr_0.03MoO_19.985 < Ba₇Nb_3.97Sc_0.03MoO_19.97. Notably, both the H₂O/D₂O isotope effect and EMF measurements indicate that the proton conduction – if there is any – is negligibly small, and the Sc and Zr-doped Ba₇Nb₄MoO₂₀ is essentially an oxide ion conductor in the temperature range studied in this work.

Ba7Nb4MoO20在600-800°C具有可接受的高离子电导率，在高温固态电化学器件中具有潜在的应用前景。目前，为了改善Ba7Nb4MoO20的电学性能，大部分的研究都集中在同价掺杂和给体掺杂上。在这项工作中，采用了一种受体掺杂策略，通过掺杂Sc和Zr来部分取代Nb。从而形成更多的空氧位进行电荷补偿，导致质子浓度按照水合Ba7Nb4MoO20 <； Ba7Nb3.97Zr0.03MoO19.985 < Ba7Nb3.97Sc0.03MoO19.97的组成顺序递增。值得注意的是，H2O/D2O同位素效应和EMF测量都表明，质子传导-如果有的话-是可以忽略不计的小，并且Sc和zr掺杂的Ba7Nb4MoO20在本工作研究的温度范围内基本上是氧化物离子导体。

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引用次数: 0

Cation disorder and lithium conductivity in mechanochemically synthesized chloride solid electrolytes 机械化学合成氯化物固体电解质中的阳离子无序性和锂电导率

IF 3 4区材料科学 Q3 CHEMISTRY, PHYSICAL

Solid State Ionics

Pub Date : 2025-10-01 Epub Date: 2025-07-08 DOI: 10.1016/j.ssi.2025.116952

Raül Artal , Henrik Lyder Andersen , Rafael Del Olmo , Irune Villaluenga , Isabel Sobrados , Virginia Diez-Gómez , Javier Gainza , María Teresa Fernández-Diaz , José Antonio Alonso , Ricardo Jimenez , Ainara Aguadero

Developing fast, stable, and scalable Li conductors is crucial for advancing all-solid-state batteries (ASSBs). Here, we present a rapid, one-hour mechanochemical synthesis of chloride electrolytes Li₂B_xCl₄ (B = Zn, Mg, Zr and x = 1 and 2/3) via high-energy ball milling (HEBM), achieving the targeted spinel phase without the need for any annealing steps. In Li₂ZnCl₄ electrochemical impedance spectroscopy reveals an unexpected, reversible low-temperature ionic transition at ∼75 °C, leading to a dramatic increase in total Li⁺ conductivity, from 2.95·10⁻⁹ S·cm⁻¹ at 25 °C to an extrapolated room temperature conductivity of 3.24·10⁻⁵ S·cm⁻¹ following heating to 125 °C. To elucidate the structural origins of this transition, we employ neutron powder diffraction (NPD), variable-temperature powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), and ⁶Li MAS NMR spectroscopy. We explore the stabilization of the high conducting phase via the introduction of host cation vacancies and therefore increasing the Li/B ratio based on the spinel-related compounds, Li₂Zn_1/3Zr_1/3Cl₄ and Li₂Mg_1/3Zr_1/3Cl₄, synthesized via the same one-hour mechanochemical approach. Rietveld refinement of NPD data reveals a monoclinic lattice distortion and cation disorder in both compounds, which open new Li conduction pathways. In both materials, 2–4 orders of magnitude increase of conductivity is achieved by aliovalent Zr⁴⁺-substitution compared to the undoped counterparts Li₂ZnCl₄ and Li₂MgCl₄, leading to maximum bulk conductivities up to 10⁻⁴ S·cm⁻¹ at room temperature. Notably, the investigated chloride-based solid electrolytes consist of non-critical elements and exhibit high thermal stability up to at least 190 °C which can be key for easy scalable processing. These results highlight the potential of spinel-based chloride electrolytes as candidates for next-generation solid-state battery applications, combining rapid and scalable synthesis with promising ionic transport properties.

开发快速、稳定、可扩展的锂导体对于推进全固态电池（assb）至关重要。在这里，我们通过高能球磨（HEBM）快速，1小时的机械化学合成氯电解质Li2BxCl4 (B = Zn, Mg， Zr和x = 1和2/3)，无需任何退火步骤即可获得目标尖晶石相。在Li2ZnCl4中，电化学阻抗谱揭示了一个意想不到的，可逆的低温离子转变，导致Li+的总电导率急剧增加，从25°C时的2.95·10−9 S·cm−1到加热到125°C时的外推室温电导率为3.24·10−5 S·cm−1。为了阐明这种转变的结构来源，我们采用了中子粉末衍射（NPD）、变温粉末x射线衍射（PXRD）、差示扫描量热法（DSC）和6Li MAS NMR波谱。我们通过同样的1小时机械化学方法合成尖晶石相关化合物Li2Zn1/3Zr1/3Cl4和Li2Mg1/3Zr1/3Cl4，探索了通过引入主阳离子空位来稳定高导电相，从而提高Li/B比的方法。NPD数据的Rietveld细化揭示了这两种化合物的单斜晶格畸变和阳离子无序，开辟了新的锂传导途径。在这两种材料中，与未掺杂的Li2ZnCl4和Li2MgCl4相比，通过价Zr4+取代，电导率提高了2-4个数量级，导致室温下的最大体电导率高达10−4 S·cm−1。值得注意的是，所研究的氯化物基固体电解质由非关键元素组成，并表现出高达至少190°C的高热稳定性，这是易于扩展加工的关键。这些结果突出了尖晶石基氯化物电解质作为下一代固态电池应用的候选材料的潜力，结合了快速、可扩展的合成和有前途的离子传输特性。

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引用次数: 0

Study on the liquid-phase oxidation preparation of nickel-manganese composite oxides and their performance in high-voltage LiNi0.5Mn1.5O4 synthesis 液相氧化法制备镍锰复合氧化物及其在高压LiNi0.5Mn1.5O4合成中的性能研究

IF 3 4区材料科学 Q3 CHEMISTRY, PHYSICAL

Solid State Ionics

Pub Date : 2025-10-01 Epub Date: 2025-06-09 DOI: 10.1016/j.ssi.2025.116914

Xingjie Zhou , Haifeng Wang , Jiawei Wang , Hao Wang , Dehua Ma , Zhengqing Pei , Ju Lu , Kexin Zheng

Due to its high operating voltage, high safety, and low cost, spinel-type lithium nickel manganese oxide(LiNi_0.5Mn_1.5O₄) has become a research hotspot in the field of lithium-ion battery cathode materials in recent years. In this study, a new lithium nickel manganese oxide precursor, a nickel‑manganese composite oxide, was prepared using a liquid-phase oxidation method, and the cathode material was synthesized through high-temperature calcination. The effects of different raw material ratios on the preparation of LiNi_0.5Mn_1.5O₄ and their mechanisms were investigated. Considering that acetylene black tends to undergo thermal decomposition and electrochemical reactions in high voltage systems, leading to degradation and performance decline, Super C65 was used as a conductive agent instead of acetylene black to achieve better electrochemical performance. The experimental results indicate that when the Ni/Mn molar ratio is 1:2.5, the resulting nickel‑manganese composite oxide exhibits good crystallinity and a Fd-3 m space group structure with uniform particle dispersion and weak agglomeration. When mixed with LiOH and subjected to high-temperature calcination, with a Li/M molar ratio (M = Mn + Ni) of 0.51, the formation of the Li_xNi_1-xO impurity phase and the polarization of the material were significantly improved. The prepared LiNi_0.5Mn_1.5O₄ has uniform particle size, well-defined octahedral morphology, and pure phase characteristics. At a current density of 0.2C, the initial discharge specific capacity reaches 135 mAh/g and remains at 118 mAh/g after 200 cycles. After replacing acetylene black with Super C65, the initial discharge specific capacity of LiNi_0.5Mn_1.5O₄ at 0.2C increased to 140 mAh/g, with a discharge specific capacity of 122 mAh/g after 200 cycles, and the electrochemical impedance decreased from 304 Ω to 266 Ω. This improvement is attributed to the smaller particle size of Super C65, which can embed between the spinel material particles to form a good conductive network, increase the lattice parameters of the disordered space cluster structure, provide more diffusion paths for ions, facilitate the rapid change of element valence states, and thereby demonstrate higher electronic conductivity. Although the cycling retention slightly decreased, the overall electrochemical performance was enhanced.

尖晶石型锂镍锰氧化物（LiNi0.5Mn1.5O4）因其工作电压高、安全性高、成本低等优点，近年来成为锂离子电池正极材料领域的研究热点。本研究采用液相氧化法制备了一种新的锂镍锰氧化物前驱体——镍锰复合氧化物，并通过高温煅烧合成了正极材料。研究了不同原料配比对制备LiNi0.5Mn1.5O4的影响及其机理。考虑到乙炔黑在高压体系中容易发生热分解和电化学反应，导致降解和性能下降，选用Super C65代替乙炔黑作为导电剂，以获得更好的电化学性能。实验结果表明，当Ni/Mn摩尔比为1:25 .5时，所制得的镍锰复合氧化物结晶度好，具有Fd-3 m的空间基团结构，颗粒分散均匀，团聚性弱。当Li/M摩尔比（M = Mn + Ni）为0.51时，LixNi1-xO杂质相的形成和材料的极化明显改善。制备的LiNi0.5Mn1.5O4粒度均匀，八面体形貌清晰，相特征纯净。在电流密度为0.2C时，初始放电比容量达到135 mAh/g，循环200次后保持在118 mAh/g。用Super C65代替乙炔黑后，LiNi0.5Mn1.5O4在0.2C下的初始放电比容量提高到140 mAh/g，循环200次后放电比容量达到122 mAh/g，电化学阻抗从304 Ω下降到266 Ω。这是因为Super C65的粒径更小，可以嵌入尖晶石材料颗粒之间形成良好的导电网络，增加无序空间团簇结构的晶格参数，为离子提供更多的扩散路径，促进元素价态的快速变化，从而表现出更高的电子导电性。虽然循环滞留率略有下降，但整体电化学性能有所提高。

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引用次数: 0

Exploring the reaction process and properties of γ-Ce2S3 derived from pure and Na-doped CeO2 sulfurization with CS2 探讨了纯CeO2和na掺杂CeO2与CS2硫化所得γ-Ce2S3的反应过程和性质

IF 3 4区材料科学 Q3 CHEMISTRY, PHYSICAL

Solid State Ionics

Pub Date : 2025-10-01 Epub Date: 2025-07-22 DOI: 10.1016/j.ssi.2025.116965

Fusheng Song , Hongbing Wei , Zongyang Shen , Zhumei Wang , Yueming Li

The sulfurization pathways of pure and Na-doped CeO₂ with CS₂ were investigated to elucidate the mechanism by which Na⁺ doping lowers γ-Ce₂S₃ synthesis temperature. For undoped CeO₂, the synthesis of γ-Ce₂S₃ typically encompasses three primary steps: (1) deoxidation, where oxygen in CeO₂ is substituted by sulfur to form CeS₂; (2) reduction of CeS₂ to α-Ce₂S₃; (3) a phase transition sequence from α-Ce₂S₃ to β-Ce₂S₃, and subsequently to γ-Ce₂S₃. This process requires a high synthesis temperature of up to 1300 °C. Remarkably, Na⁺ introduction fundamentally altered this pathway, bypassing α and β intermediates to directly yield pure γ-Ce₂S₃ at 900 °C. This is attributed to Na⁺-promoted formation of NaCeS₂ and Ce₂O₂S intermediates that facilitate direct γ-phase crystallization. The resultant γ-[Na]-Ce₂S₃ solid solution exhibits modified band structure and enhanced thermal stability compared to undoped γ-Ce₂S₃.

研究了纯CeO2和Na掺杂CeO2与CS₂的硫化途径，阐明了Na+掺杂降低γ-Ce2S3合成温度的机理。对于未掺杂的CeO2， γ-Ce2S3的合成通常包括三个主要步骤：(1)脱氧，其中CeO2中的氧被硫取代形成CeS2；(2) CeS2还原为α-Ce2S3；(3) α-Ce2S3→β-Ce2S3→γ-Ce2S3的相变序列。该工艺需要高达1300°C的高合成温度。值得注意的是，Na+的引入从根本上改变了这一途径，绕过α和β中间体，在900°C下直接生成纯γ-Ce2S3。这是由于Na+促进了NaCeS2和Ce2O2S中间体的形成，促进了γ相的直接结晶。与未掺杂的γ-[Na]- ce2s3相比，得到的γ-[Na]- ce2s3固溶体具有改变的能带结构和增强的热稳定性。

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引用次数: 0

Ion emission efficiency of Ag+ ions from silver ion-conducting glass under atmospheric pressure 银离子导电玻璃中银离子在大气压下的离子发射效率

IF 3 4区材料科学 Q3 CHEMISTRY, PHYSICAL

Solid State Ionics

Pub Date : 2025-10-01 Epub Date: 2025-06-23 DOI: 10.1016/j.ssi.2025.116941

Daigo Ito, Daisuke Urushihara, Yusuke Daiko

By sharpening ion-conductive glass and applying a high voltage, conducting species ions are released from the glass tip. The ion emission of Ag⁺ ions under atmospheric pressure was investigated. Under atmospheric pressure, there is a possibility that various ions are produced as a result of corona discharge. To analyze the efficiency of Ag⁺ ion emission from the tip of sharpening glass, a quartz crystal microbalance was used to simultaneously measure the mass of the emitted ions and the ion current value. In an air atmosphere at room temperature, the efficiency of Ag⁺ ion emission was only ∼20 %. The efficiency tended to decrease further in an oxygen atmosphere. On the other hand, the emission efficiency reaches approximately 100 % in N₂ atmosphere. The efficiency of Ag⁺ ion emission under atmospheric pressure with various conditions are discussed in this paper.

通过磨尖离子导电玻璃并施加高压，导电物质离子从玻璃尖端释放出来。研究了Ag+离子在常压下的离子发射。在大气压力下，由于电晕放电，有可能产生各种离子。为了分析锐化玻璃尖端Ag+离子的发射效率，采用石英晶体微天平同时测量了发射离子的质量和离子电流值。在室温的空气环境中，Ag+离子的发射效率仅为~ 20%。在含氧气氛中，效率有进一步降低的趋势。另一方面，在N2气氛中，排放效率达到约100%。本文讨论了不同条件下常压下银离子的发射效率。

引用次数: 0

Change of electrochemical potential and entropy of Li around an edge dislocation in solid electrolytes 固体电解质中锂在边缘位错周围的电化学电位和熵的变化

IF 3 4区材料科学 Q3 CHEMISTRY, PHYSICAL

Solid State Ionics

Pub Date : 2025-10-01 Epub Date: 2025-07-03 DOI: 10.1016/j.ssi.2025.116950

Kyuichi Yasui, Koichi Hamamoto

The equations of the electrochemical potential and entropy of Li atoms near an edge dislocation inside solid electrolytes are derived. Although a stress field becomes complex in the presence of many dislocations in polycrystalline materials, the equations are still valid and the qualitative conclusions are robust at least for lower dislocation density than about

10^{16}

m^{- 2}

. As the modified electrochemical potential of

{Li}^{+}

ions in a stress field is spatially uniform at equilibrium in solid electrolytes due to the high mobility of

{Li}^{+}

ions, the spatial variations of the entropies associated with the stress and electric-potential field are obtained. From the increase in the local entropy by a positively charged dislocation, the concentration of Frenkel pairs of

{Li}^{+}

interstitials and vacancies is derived, which could be considerably higher near the dislocation. It could be the reason for higher ionic conductivity along a dislocation. It is suggested that a dislocation should be positively charged in an ionic conductor of positive ions in the absence of impurities. When the dilation due to

{Li}^{+}

interstitials is relatively large, reduction or oxidation of the solid electrolyte may possibly occur near a dislocation although considerable diffusion of atoms and electrons is necessary for it.

导出了固体电解质中锂原子在边缘位错附近的电化学电位和熵的方程。尽管在多晶材料中存在许多位错时应力场变得复杂，但至少在位错密度低于1016 m−2时，方程仍然有效，定性结论是稳健的。由于Li+离子的高迁移率，Li+离子在应力场中处于平衡状态时的电化学势在空间上是均匀的，得到了与应力场和电势场相关的熵在空间上的变化。由带正电的位错引起的局域熵的增加，导出了Li+间隙和空位的Frenkel对的浓度，在位错附近可能会相当高。这可能是沿位错方向离子电导率较高的原因。本文认为，在不含杂质的正离子导体中，位错应带正电荷。当由Li+间隙引起的膨胀相对较大时，固体电解质可能在位错附近发生还原或氧化，尽管这需要相当大的原子和电子扩散。

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引用次数: 0

High temperature oxygen exchange reaction on dense and porous La0.6Sr0.4CoO3-δ electrodes: An overview of the experimental evidence for modeling 致密多孔La0.6Sr0.4CoO3-δ电极上的高温氧交换反应：模拟实验证据综述

IF 3 4区材料科学 Q3 CHEMISTRY, PHYSICAL

Solid State Ionics

Pub Date : 2025-10-01 Epub Date: 2025-07-26 DOI: 10.1016/j.ssi.2025.116973

Tatsuya Kawada

<div><div>Oxygen exchange kinetics was investigated to model the current-potential relationship of mixed conducting oxide electrodes used in SOFC and SOEC. Focusing on La0.6Sr0.4CoO3 as a model material, experimental evidence so far obtained in our group were summarized and reanalyzed. The reaction order analysis suggested a complex reaction mechanism, for which we came to think of two series kinetics, surface process and subsurface process. The former refers to an exchange process between gas-phase oxygen molecules and some sort of surface oxygen species. The latter refers to the exchange of surface oxygen with bulk oxide ions, and the reaction barrier is not necessarily oxygen transport, but may be electron transport/transfer for oxygen in/ex-corporation This hypothesis appeared to resolve some of our remaining questions regarding the experimental results, such as scattered pO2 dependence in high partial pressure range, the higher isotope exchange rates than electrochemical impedance, and the reaction rate enhancement in the presence of the LaSrCoO4 phase. While a single piece of such experimental evidence is insufficient to prove the hypothesis, considering all the results together provides strong support. We then tried to separate the contributions of surface and subsurface processes by measuring the surface oxygen potential using a porous oxygen sensor. It revealed that the surface process is written as <math><msub><mi>J</mi><mi>s</mi></msub><mo>=</mo><msub><mi>J</mi><mrow><mi>s</mi><mo>,</mo><mn>0</mn></mrow></msub><mo>∙</mo><mi>δ</mi><mo>∙</mo><mfenced><mrow><msubsup><mi>a</mi><mrow><mi>O</mi><mo>,</mo><mi>s</mi></mrow><mn>2</mn></msubsup><mo>−</mo><msub><mi>p</mi><mrow><msub><mi>O</mi><mn>2</mn></msub><mo>,</mo><mi>g</mi></mrow></msub></mrow></mfenced></math> and the subsurface process as <math><msub><mi>J</mi><mi>ss</mi></msub><mo>=</mo><msub><mi>J</mi><mrow><mi>ss</mi><mo>,</mo><mn>0</mn></mrow></msub><mo>∙</mo><mfenced><mrow><msub><mi>a</mi><mrow><mi>O</mi><mo>,</mo><mi>e</mi></mrow></msub><msubsup><mi>a</mi><mrow><mi>O</mi><mo>,</mo><mi>s</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msubsup><mo>−</mo><msubsup><mi>a</mi><mrow><mi>O</mi><mo>,</mo><mi>e</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msubsup><msub><mi>a</mi><mrow><mi>O</mi><mo>,</mo><mi>s</mi></mrow></msub></mrow></mfenced><mo>=</mo><msub><mi>J</mi><mrow><mi>ss</mi><mo>,</mo><mn>0</mn></mrow></msub><mfenced><mrow><mi>exp</mi><mfenced><mfrac><mrow><mi>β</mi><mo>∆</mo><msub><mi>μ</mi><msub><mi>O</mi><mn>2</mn></msub></msub></mrow><mi>RT</mi></mfrac></mfenced><mo>−</mo><mi>exp</mi><mfenced><mrow><mo>−</mo><mfrac><mrow><mfenced><mrow><mn>1</mn><mo>−</mo><mi>β</mi></mrow></mfenced><mo>∆</mo><msub><mi>μ</mi><msub><mi>O</mi><mn>2</mn></msub></msub></mrow><mi>RT</mi></mfrac></mrow></mfenced></mrow></mfenced></math>, which are in good agreement with the experimental data even for f

为了模拟SOFC和SOEC中混合导电氧化物电极的电流-电位关系，研究了氧交换动力学。以La0.6Sr0.4CoO3为模型材料，对本课题组目前获得的实验证据进行总结和重新分析。反应顺序分析表明反应机理复杂，可分为表面过程和次表面过程两个系列动力学。前者是指气相氧分子与某种表面氧之间的交换过程。后者是指表面氧与大块氧化离子的交换，反应屏障不一定是氧输运，而可能是电子输运/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧在/氧之间的转移。这一假设似乎解决了我们对实验结果的一些遗留问题，如在高分压范围内分散的pO2依赖性，同位素交换速率高于电化学阻抗，在LaSrCoO4相存在下，反应速率提高。虽然单个这样的实验证据不足以证明这一假设，但综合考虑所有的结果，就提供了强有力的支持。然后，我们尝试通过使用多孔氧传感器测量表面氧势来分离表面和地下过程的贡献。结果表明，表面过程为Js=Js,0∙δ∙aO,s2−pO2,g，地下过程为Jss=Jss,0∙aO,eaO,s−1−aO,e−1aO,s=Jss,0expβ∆μO2RT - exp−1−β∆μO2RT，即使在不同氧空位形成能的薄膜上也与实验数据吻合较好。对于多孔电极的建模，基于实验证据，我们认为没有必要考虑亚表面过程，例如多孔电极中颗粒表面的面积比反应速率高于膜电极，以及LaSrCoO4相缺乏增强作用。将j应用于传输线模型所估计的电流-电压关系与实验结果吻合较好。

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