Journal of Rare Earths最新文献_第9页

Cerium's role in transformation of inclusions and precipitated phases in Ferrium M54 steel ingots 铈在M54钢锭中夹杂物和析出相转变中的作用

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2025-02-26 DOI: 10.1016/j.jre.2025.02.020

Hongchun Zhu , Hanxun Luo , Huabing Li , Zhiyu He , Zhuowen Ni , Zhengrong Ai , Zhouhua Jiang , Hao Feng , Shucai Zhang

The addition of Ce significantly enhances cleanliness of steel and modifies precipitation phases. However, there are differences in the effects of different alloy systems, especially its role in M54 steel is insufficiently understood. This study investigates the evolution of inclusions and precipitation phases in M54 steel ingots with varying Ce additions. Results indicate that the addition of Ce reduces the content of impurity elements (O and S) and transforms Mg and Al inclusions into Ce inclusions, which is due to the stronger affinity between Ce and impurity elements such as O and S. Ce inclusions serve as nucleation sites for dendrites, reducing secondary dendrite arm spacing. In addition, these inclusions and Ce-containing precipitated phase also act as nucleation sites for carbide precipitates, effectively refining their distribution by reducing growth spaces and increasing nucleation density. Notably, as Ce content increases from 0 to 0.01 wt%, the precipitation phase content decreases significantly but rises slightly with further increases in Ce content due to the formation of additional Ce-containing precipitates. By quantitatively comparing the dendrite arm spacing, cleanliness, content and size of precipitated phase, it is determined that the optimum addition amount of Ce for M54 steel is about 0.01 wt%.

Ce的加入显著提高了钢的清洁度，改变了析出相。然而，不同合金体系的效果存在差异，特别是其在M54钢中的作用尚不充分了解。研究了添加不同Ce的M54钢锭中夹杂物和析出相的演变规律。结果表明，Ce的加入降低了杂质元素（O和S）的含量，使Mg和Al包裹体转变为Ce包裹体，这是由于Ce与杂质元素（O和S）的亲和力更强，Ce包裹体作为枝晶的成核位点，减小了次生枝晶臂间距。此外，这些夹杂物和含ce的析出相也作为碳化物析出相的成核位点，通过减小生长空间和提高成核密度，有效地细化了碳化物析出相的分布。值得注意的是，当Ce含量从0 wt%增加到0.01 wt%时，析出相含量显著降低，但随着Ce含量的进一步增加，由于形成了额外的含Ce析出相，析出相含量略有上升。通过定量比较枝晶臂间距、析出相清洁度、含量和尺寸，确定M54钢的最佳Ce添加量为0.01% wt%左右。

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引用次数: 0

Electronic, magnetic, optical, and thermoelectric properties of rare earth-based CaCe2(S/Se)4 spinels for spintronic and energy harvesting applications 稀土基CaCe2(S/Se)4尖晶石用于自旋电子和能量收集的电子、磁性、光学和热电性质

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2025-02-25 DOI: 10.1016/j.jre.2025.02.017

A. Qadoos , Muhammad Rashid , Noura Dawas Alkhaldi , Nadi Mlihan Alresheedi , Imed Boukhris , Q. Mahmood , M.N. Nasir

Spinels are an emerging class of advanced technological materials for spintronic, energy harvesting, and water-splitting applications. In this work, we explored the electronic, magnetic, optical, and transport properties of CaCe₂(S/Se)₄ by density functional theory based on the Wien2k code. The energy released during optimization in ferromagnetic and antiferromagnetic states confirms that the ferromagnetic state is stable, which is further verified by negative formation energy. Heisenberg model and density of states report the Curie temperature and spin polarization. Half metallic ferromagnetism (HMF) regarding hybridization, crystal fields, exchange energies, and double exchange mechanisms is discussed. The transfer of magnetic moments from Ce to Ca and S/Se and interstitial sites ensure the role of spin of electrons rather than clustering. Moreover, the optical properties are addressed by dielectric constants, absorption, refraction, and optical loss. The first absorption peaks exist in infrared zone; others fall in visible to ultraviolet zones. The spin-up (↑) and spin-down (↓) channel thermoelectric factors combine and report the performance by conductivities, Seebeck coefficient, and power factor. Therefore, the studied materials' optical and thermoelectric behaviours will allow researchers to realize them for technological applications.

尖晶石是一类新兴的先进技术材料，用于自旋电子，能量收集和水分解应用。本文基于Wien2k编码，利用密度泛函理论研究了CaCe2(S/Se)4的电子、磁性、光学和输运性质。优化过程中铁磁态和反铁磁态释放的能量证实了铁磁态是稳定的，负地层能进一步验证了这一点。海森堡模型和态密度报告了居里温度和自旋极化。讨论了半金属铁磁性（HMF）的杂化、晶体场、交换能和双交换机制。磁矩从Ce到Ca、S/Se和间隙位的转移保证了电子的自旋作用而不是聚类作用。此外，光学性质由介电常数、吸收、折射和光损耗来确定。第一个吸收峰存在于红外区；其他则落在可见到紫外线的区域。自旋向上（↑）和自旋向下（↓）通道热电因子结合并通过电导率、塞贝克系数和功率因子报告性能。因此，研究材料的光学和热电行为将使研究人员能够实现它们的技术应用。

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引用次数: 0

Highly effective and selective recovery of scandium using high-surface area silica prepared from calcium silicate hydrate 水合硅酸钙制备的高比表面积二氧化硅高效、选择性地回收钪

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2025-02-21 DOI: 10.1016/j.jre.2025.02.011

Lei Shi , Chunlin He , Xinsheng Li

A novel method for scandium recovery is proposed through high-surface area silanol-rich silica sorbents which were prepared with calcium silicate hydrate (C-S-H) as raw material. Two types of silanol-rich silica particles, i.e., LAC-S (silica derived from acid leaching of amorphous C-S-H) and LLC-S (silica derived from acid leaching of low-crystallinity C-S-H) are obtained after calcium ions are removed from both amorphous and low-crystallinity forms of C-S-H through a facile acid leaching process (3 mol/L, 25 °C, 24 h). ²⁹Si NMR spectroscopy reveals that the proportion of silicon atoms carrying silanol groups increases from less than 43% to over 80% when silica particles are transferred from a dry state to an aqueous solution. Batch adsorption experiments were conducted to evaluate the sorption performance and selectivity of these silica sorbents toward Sc(III).The scandium sorption capacities of LAC-S and LLC-S at an equilibrium pH of 4.2 are 174.45 and 129.57 mg/g, respectively. The separation factors (SF_Sc/Ln) of both silica particles exceed 1000 in the initial pH range of 3.5–5. The loaded scandium ions are recovered with 3 mol/L hydrochloric acid and the sorbents exhibit good reusability. This strategy provides an efficient and green method for recovering scandium from aqueous solutions.

提出了一种以水合硅酸钙（C-S-H）为原料制备高比表面积富硅醇硅吸附剂回收钪的新方法。通过3 mol/L、25℃的简单酸浸工艺，将C- s - h的无定形和低结晶度形态中的钙离子去除，得到了两种富硅醇的二氧化硅颗粒，即LAC-S（非晶态C- s - h酸浸所得的二氧化硅）和LLC-S（低结晶度C- s - h酸浸所得的二氧化硅）。29Si核磁共振光谱显示，当硅颗粒从干燥状态转移到水溶液中时，硅原子携带硅醇基团的比例从不到43%增加到80%以上。通过批量吸附实验，评价了这些二氧化硅吸附剂对Sc（III）的吸附性能和选择性。LAC-S和LLC-S在平衡pH为4.2时的钪吸附量分别为174.45和129.57 mg/g。在初始pH为3.5 ~ 5的范围内，两种二氧化硅颗粒的分离因子（SFSc/Ln）均大于1000。负载的钪离子用3mol /L盐酸回收，吸附剂具有良好的可重复使用性。该策略为从水溶液中回收钪提供了一种高效、绿色的方法。

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引用次数: 0

Construction of a 12-metal Zn(II)-Nd(III) nanocluster for ratiometric fluorescence detection of inflammatory marker neopterin 用于炎症标志物新蝶呤比例荧光检测的12金属Zn(II)-Nd（III）纳米簇的构建

IF 5.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2025-02-01 DOI: 10.1016/j.jre.2024.08.003

Huanyin Yu, Xiaoping Yang, Xiaoli Lv, Xianfeng Huang

A 12-metal Zn(II)-Nd(III) cluster 1 (sizes: 1.8 nm × 2.0 nm × 2.0 nm) was synthesized from a long-chain type Schiff base ligand. It displays ratiometric fluorescence response to neopterin (Neo) with high selectivity and sensitivity, which can be expressed by the equation I_{545 nm}/I_{1060 nm} = A·[Neo]² + B·[Neo] + C. 1 is used to quantitatively test Neo concentrations in fetal calf serum (FCS) and urine, and the recovery ranges are 98.57%–103.82% and 99.25%–103.50%, respectively, while the relative standard deviations (RSDs) are 7.89%–9.46% and 1.85%–4.16%, respectively. The limits of detection of 1 to Neo in FCS and urine are 0.034 and 0.021 μmol/L, respectively.

以长链希夫碱配体为原料合成了尺寸为1.8 nm × 2.0 nm × 2.0 nm的12金属Zn(II)-Nd（III）簇1。采用I545 nm/I1060 nm = A·[Neo]2 + B·[Neo] + C. 1定量测定胎牛血清（FCS）和尿液中Neo浓度，回收率分别为98.57% ~ 103.82%和99.25% ~ 103.50%，相对标准偏差（rsd）分别为7.89% ~ 9.46%和1.85% ~ 4.16%。FCS和尿液中1 ~ Neo的检出限分别为0.034和0.021 μmol/L。

引用次数: 0

Effective suppression of surface cation segregations on double perovskite oxides through entropy engineering 通过熵工程有效抑制双包晶氧化物表面阳离子偏析

IF 5.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2025-02-01 DOI: 10.1016/j.jre.2024.07.017

Zhe Wang , Mengke Yuan , Juntao Gao , Hongru Hao , Jingwei Li , Lingling Xu , Zhe Lv , Bo Wei

Cation segregation on cathode surfaces plays a key role in determining the activity and operational stability of solid oxide fuel cells (SOFCs). The double perovskite oxide PrBa_0.8Ca_0.2Co₂O_5+δ (PBCC) has been widely studied as an active cathode but still suffer from serious detrimental segregations. To enhance the cathode stability, a PBCC derived A-site medium-entropy Pr_0.6La_0.1Nd_0.1Sm_0.1Gd_0.1Ba_0.8Ca_0.2Co₂O_5+δ (ME-PBCC) oxide was prepared and its segregation behaviors were investigated under different conditions. Compared with initial PBCC oxide, the segregations of BaO and Co₃O₄ on the surface of ME-PBCC material are significantly suppressed, especially for Co₃O₄, which is attributed to its higher configuration entropy. Our results also confirm the improved electrochemical performance and structural stability of ME-PBCC material, enabling it as a promising cathode for SOFCs.

阴极表面阳离子偏析对固体氧化物燃料电池（SOFCs）的活性和运行稳定性起着关键作用。双钙钛矿氧化物PrBa0.8Ca0.2Co2O5+δ (PBCC)作为活性阴极已被广泛研究，但仍存在严重的有害偏析。为了提高阴极的稳定性，制备了PBCC衍生的a位中熵Pr0.6La0.1Nd0.1Sm0.1Gd0.1Ba0.8Ca0.2Co2O5+δ (ME-PBCC)氧化物，并研究了其在不同条件下的偏析行为。与初始PBCC氧化物相比，ME-PBCC材料表面BaO和Co3O4的分离被明显抑制，特别是Co3O4，这归因于其更高的构型熵。我们的研究结果也证实了ME-PBCC材料的电化学性能和结构稳定性的改善，使其成为sofc的有前途的阴极。

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引用次数: 0

Unusual roles of ceria as the support of a single-atom catalyst in hydroisomerization of n-heptane: Phase boundary acts as transport channels between different active centers 铈在正庚烷加氢异构化过程中作为单原子催化剂载体的不寻常作用：相界充当不同活性中心之间的传输通道

IF 5.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2025-02-01 DOI: 10.1016/j.jre.2024.02.020

Hao Qin, Hui Wan, Guofeng Guan

Hydroisomerization of n-alkanes plays an important role in fuel and lubricants processing. Bifunctional catalysts with ultralow platinum loading have recently been reported successively for hydroisomerisation. Herein, the catalysts were prepared successfully with different methods to improve the catalytic performance. The conversion of 0.01%Pt1@CeOx/SAPO-11 prepared by co-calcination method (0.01%Pt1@CS-c) is 71.4%, 25% higher than the other prepared by precipitation method. The turnover frequency per active surface platinum site (TOFPt) of 0.01%Pt1@CS-c is as high as 13115 h^–1. Revealed by the X-ray photoelectron spectroscopy (XPS) results, the quality of phase boundary/intersurface between ceria and zeolite is found significantly different. The conjunction quality of phase boundary directly affects the spillover rate of intermediate species, which further leads to an apparent activity difference. In addition, the possible role of ceria in the reaction is discussed, rather than just as a carrier for the active metal atoms.

正构烷烃的加氢异构化在燃料和润滑油加工中发挥着重要作用。近来，用于加氢异构化的超低铂载量双功能催化剂已被相继报道。本文采用不同的方法成功制备了催化剂，以提高催化性能。共煅烧法制备的 0.01%Pt1@CeOx/SAPO-11 的转化率为 71.4%，比沉淀法制备的转化率高 25%。0.01%Pt1@CS-c 每个活性表面铂位点的周转频率（TOFPt）高达 13115 h-1。X 射线光电子能谱（XPS）结果表明，铈与沸石之间的相界/内表面质量存在显著差异。相界的结合质量会直接影响中间物种的溢出率，从而进一步导致明显的活性差异。此外，还讨论了铈在反应中可能扮演的角色，而不仅仅是活性金属原子的载体。

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引用次数: 0

Extraction of rare earth elements from neodymium (NdFeB) magnet scrap using magnesium halides 利用卤化镁从钕铁硼（NdFeB）磁铁废料中提取稀土元素

IF 5.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2025-02-01 DOI: 10.1016/j.jre.2024.01.012

Sung Gue Heo , Jae Yeol Yang , Soong Ju Oh , Seok-Jun Seo , Mi Hye Lee , Kyoung-Tae Park

The demand for neodymium (NdFeB) permanent magnets for electric vehicles and eco-friendly generators is increasing. However, NdFeB magnets contain rare earth elements (REEs), which are limited in supply. In this study, we performed an exchange reaction between magnesium halides (fluoride and chloride) and waste NdFeB scrap and then compared the characteristics of the extracted halides salts. The compositions of the ternary Mg fluoride (LiF:NaF:MgF₂ = 50:40:10 in mole ratio) and chloride (LiCl:NaCl:MgCl₂ = 10:50:40 in mole ratio) salts were thermodynamically determined for achieving low eutectic temperatures. The reactions between the NdFeB scrap powder (1–2 mm) and Mg halide salts were carried out at 1073 and 873 K for the fluoride and chloride systems, respectively, in an argon atmosphere. After the reaction, we separated Nd halide from the residual salt and evaluated the Nd-extraction rate. The phase formation of the salt was analyzed using X-ray diffraction (XRD), and the extraction rate of Nd was analyzed using inductively coupled plasma optical emission spectroscopy (ICP-OES). Nd was extracted in the form of Nd halide (NdF₃ or NdCl₃), and the extraction rates in the fluoride and chloride systems are 98.64% and 84.59%, respectively. Thus, the fluoride system is more effective than the chloride system for Nd extraction. Our study provides a comprehensive comparative analysis of the effectiveness of fluoride and chloride systems in extracting REEs from NdFeB magnet scrap. Our study findings can be used to develop an effective method for recycling magnet scraps.

电动汽车和环保发电机对钕（NdFeB）永磁体的需求日益增长。然而，钕铁硼磁体含有稀土元素，而稀土元素的供应有限。在本研究中，我们在卤化镁（氟化物和氯化物）和废弃钕铁硼废料之间进行了交换反应，然后比较了提取的卤化物盐的特性。通过热力学方法确定了氟化镁（LiF:NaF:MgF2 = 50:40:10，摩尔比）和氯化镁（LiCl:NaCl:MgCl2 = 10:50:40，摩尔比）三元盐的组成，以实现低共晶温度。钕铁硼废料粉末（1-2 毫米）与卤化镁盐之间的反应是在氩气环境中分别于 1073 和 873 K 的温度下进行的。反应结束后，我们从残盐中分离出卤化钕，并评估了钕萃取率。使用 X 射线衍射 (XRD) 分析了盐的相形成，并使用电感耦合等离子体光发射光谱 (ICP-OES) 分析了钕的萃取率。钕以卤化钕（NdF3 或 NdCl3）的形式被萃取，氟化物和氯化物体系的萃取率分别为 98.64 % 和 84.59 %。因此，在萃取钕方面，氟化物体系比氯化物体系更有效。我们的研究对氟化物和氯化物体系从钕铁硼磁铁废料中提取稀土元素的有效性进行了全面的比较分析。我们的研究结果可用于开发一种回收磁铁废料的有效方法。

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引用次数: 0

Innovative pilot-scale process for sustainable rare earth oxide production from coal byproducts: A comprehensive environmental impact assessment 利用煤炭副产品生产可持续稀土氧化物的创新型试验规模工艺：综合环境影响评估

IF 5.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2025-02-01 DOI: 10.1016/j.jre.2024.04.004

Mohsen Rabbani , Joshua Werner , Ario Fahimi , Ehsan Vahidi

This study developed a pilot-scale process feeding with two different materials resulting from a column leaching process and acid mine drainage (AMD) streams to recover rare earth elements (REEs). A life cycle assessment (LCA) study was done to evaluate the environmental impacts of rare earth production from deleterious material in the form of highly contaminated leachate (HCL) and low-contaminated leachate (LCL). The results indicate that the main contributors to environmental categories that produce RE-hydroxide stages are NaOH and electricity. Also, oxalic acid, Na₂CO₃, and hydrochloric acid significantly contribute to the production stage of individual rare earth oxides (REOs), including solvent extraction (SX) and precipitation steps. The HCL route has higher environmental impacts than LCL due to higher chemical/energy and H₂SO₄ usage, so 468 and 292 kg of carbon dioxide are generated to produce 1 t of individual REOs from HCL and LCL routes, respectively. Moreover, the carbon dioxide emitted from the process, including the RE-hydroxide production, SX, and REOs production, is less than 10 t CO₂. A sensitivity analysis was also performed to assess the changeability of the environmental footprints of the main inputs in the SX process, as the main stage has a higher contribution to the whole process. This LCA study is the first step toward understanding the environmental influence of new processing methods to produce REEs from coal by-products through a developed pilot-scale process.

本研究开发了一种中试工艺，采用柱式浸出过程和酸性矿山排水（AMD）流产生的两种不同材料进行进料，以回收稀土元素（REEs）。采用生命周期评价（LCA）方法对高污染渗滤液（HCL）和低污染渗滤液（LCL）两种有害物质生产稀土的环境影响进行了评价。结果表明，产生re - oh阶段的主要环境类别是NaOH和电。此外，草酸、Na2CO3和盐酸对单个稀土氧化物（REOs）的生产阶段有显著影响，包括溶剂萃取（SX）和沉淀步骤。由于化学/能源和H2SO4的使用量更高，HCL路线比LCL路线对环境的影响更大，因此HCL和LCL路线分别产生468和292公斤二氧化碳，以生产1吨单个reo。此外，该过程中排放的二氧化碳，包括氢氧化re的生产、SX和REOs的生产，都小于10 t CO2。由于主要阶段对整个过程的贡献较大，因此还进行了敏感性分析，以评估SX过程中主要投入物的环境足迹的可变性。这项LCA研究是了解通过开发的中试规模工艺从煤副产品中生产稀土的新加工方法对环境影响的第一步。

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引用次数: 0

An improved method to evaluate trap depth from thermoluminescence 从热释光评估陷阱深度的改进方法

IF 5.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2025-02-01 DOI: 10.1016/j.jre.2024.02.004

Shiyou Zhang, Fangyi Zhao, Shengqiang Liu, Zhen Song, Quanlin Liu

Rare earth-doped inorganic compounds contribute mostly to the family of persistent luminescent materials due to the versatile energy levels of rare earth ions. One of the key research aims is to match the trap level stemming from the doped rare earth ion or intrinsic defects to the electronic structure of the host, and therefore thermoluminescence measurement becomes a radical technology in studying trap depth, which is one of the significant parameters that determine the properties of persistent luminescence and photostimulated luminescence. However, the results of trap depth obtained by different thermoluminescence methods are quite different so that they are not comparable. Herein, we analyzed different thermoluminescence methods, selected and improved the traditional peak position method of T_m/500 to be E = (−0.94lnβ+30.09)kT_m. Only the experimental heating rate (β) is needed additionally, but the accuracy is improved greatly in most cases. This convenient and accurate method will accelerate the discovery of novel rare earth-doped materials.

稀土掺杂无机化合物由于稀土离子的多能级特性，在持续发光材料家族中占有重要地位。将稀土离子或本禀缺陷所产生的陷阱能级与基体的电子结构相匹配是关键的研究目标之一，因此热致发光测量成为研究陷阱深度的一项重要技术，而陷阱深度是决定持续发光和光激发发光性能的重要参数之一。然而，不同热释光方法得到的陷阱深度结果差异较大，不具有可比性。本文对不同的热释光方法进行了分析，选择并改进了传统的Tm/500峰位法为E =(−0.94lnβ+30.09)kTm。只需要增加实验升温速率（β），但在大多数情况下精度大大提高。这种简便、准确的方法将加速发现新型稀土掺杂材料。

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引用次数: 0

Giant low-field magnetocaloric effect in unstable antiferromagnetic Tm1–xErxNi2Si2 (x = 0.2, 0.4) compounds 不稳定反铁磁性 Tm1-xErxNi2Si2 (x = 0.2, 0.4) 化合物中的巨型低场磁ocaloric 效应

IF 5.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2025-02-01 DOI: 10.1016/j.jre.2023.12.017

Bo Xu , Lu Tian , Junfeng Wang , Mei Wu , Xinqiang Gao , Zhenxing Li , Jun Shen

Magnetic refrigeration (MR) technology is regarded as an ideal solution for cryogenic applications, relying on magnetocaloric materials which provide necessary chilling effect. A series of polycrystalline Tm_1–xEr_xNi₂Si₂ (x = 0.2, 0.4) compounds was synthesized, and their magnetic properties, magnetic phase transition together with magnetocaloric effect (MCE) were studied. The Tm_1–xEr_xNi₂Si₂ (x = 0.2, 0.4) compounds display a field-induced metamagnetic transition from antiferromagnetic (AFM) to ferromagnetism (FM) in excess of 0.2 T, respectively. Meanwhile, the AFM ground state is unstable. Under the field change of 0–2 T, the values of maximal magnetic entropy change (

- {Δ S}_{M}^{\max}

) and refrigerant capacity (RC) for Tm_0.8Er_0.2Ni₂Si₂ compound are 17.9 J/(kg·K) and 83.5 J/kg, respectively. The large reversible MCE under low magnetic fields (≤2 T) indicates that Tm_0.8Er_0.2Ni₂Si₂ compound can serve as potential candidate materials for cryogenic magnetic refrigeration.

磁制冷（MR）技术被认为是低温应用的理想解决方案，它依赖于能提供必要制冷效果的磁致冷材料。我们合成了一系列多晶 Tm1-xErxNi2Si2 (x = 0.2, 0.4) 化合物，并研究了它们的磁性能、磁相变和磁致冷效应（MCE）。Tm1-xErxNi2Si2 (x = 0.2, 0.4) 化合物在超过 0.2 T 时分别显示出磁场诱导的从反铁磁性（AFM）到铁磁性（FM）的元磁转变。同时，AFM 基态并不稳定。在 0-2 T 的磁场变化下，Tm0.8Er0.2Ni2Si2 化合物的最大磁熵变（-ΔSMmax）和制冷剂容量（RC）值分别为 17.9 J/(kg-K) 和 83.5 J/kg。在低磁场（≤2 T）条件下的大可逆 MCE 表明，Tm0.8Er0.2Ni2Si2 化合物可作为低温磁制冷的潜在候选材料。

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引用次数: 0