Journal of Rare Earths最新文献

{"title":"Optimizing terbium content in Tb-Cu-Al grain boundary diffusion to significantly enhance coercivity of Nd-Fe-B sintered magnets","authors":"Tao Luo, Jianqiang Lin, Chengzhi Sun, Xin Ming, Lichen Wang, Jungang Cheng, Jian Zhang, Baogen Shen","doi":"10.1016/j.jre.2025.09.008","DOIUrl":"10.1016/j.jre.2025.09.008","url":null,"abstract":"<div><div>Developing high-coercivity grain boundary diffusion (GBD) Nd-Fe-B thick magnets (>5 mm) is crucial for advanced motor applications. Multicomponent alloys combining heavy rare earth (HRE) with auxiliary elements (e.g., Cu/Al) are currently the most widely used diffusion sources in GBD, but the optimal composition remains unclear, and diffusion sources with high HRE content (∼70 at%) are mostly adopted, which limits the further improvements in coercivity and HRE utilization efficiency of diffused magnets. This study focuses on the commonly used diffusion elements Tb, Cu, and Al, systematically optimizing the ratio between HRE (Tb) and auxiliary elements (Cu/Al) in Tb-Cu-Al diffusion sources. Through one-step diffusion with a reduced HRE content (50 at%) diffusion source, we achieved a breakthrough in coercivity enhancement (Δ<em>H</em><sub>cj</sub>) for thick magnets while simultaneously obtaining dual high performance in both coercivity and its enhancement. The Tb<sub><em>x</em></sub>Al<sub>50−<em>x</em>/2</sub>Cu<sub>50−<em>x</em>/2</sub> (<em>x</em> = 40 at%, 50 at%, 65 at%) diffusion sources were fabricated by magnetron sputtering. After diffusion treatment, the Tb<sub>50</sub>Cu<sub>25</sub>Al<sub>25</sub> (50 at% Tb) diffused thick magnet (6 mm) exhibits a remarkable Δ<em>H</em><sub>cj</sub> of 11.49 kOe (from 16.73 to 28.22 kOe), significantly outperforming magnets with higher (65 at%, Δ<em>H</em><sub>cj</sub> = 9.96 kOe) and lower Tb content (40 at%, Δ<em>H</em><sub>cj</sub> = 10.57 kOe) diffusion sources. And the thermal stability of Tb<sub>50</sub>Cu<sub>25</sub>Al<sub>25</sub> diffused magnets improves markedly, with the coercivity temperature coefficient (<em>β</em><sub><em>H</em>cj</sub>) improving from −0.535%/°C in the original magnet to −0.457%/°C. The diffusion mechanism study reveals that the Tb<sub>50</sub>Cu<sub>25</sub>Al<sub>25</sub> diffusion source suppresses the chemically induced liquid film migration (CILFM) during GBD, weakens the abnormal shell thickening and grain coarsening near the surface of the diffused magnet, leading to the formation of continuous and thin (Nd,Tb)<sub>2</sub>Fe<sub>14</sub>B shell structures. Concurrently, the highly efficient wetting effect of Cu/Al facilitates deeper Tb diffusion and more uniform Tb distribution, optimizing the diffusion kinetics and thereby significantly enhancing coercivity. Additionally, this study proposes the regulatory role of the HRE-to-auxiliary element ratio in HRE GBD kinetics, elucidating the “Tb-Cu/Al ratio balancing effect” at intermediate HRE content diffusion source (50 at%): excessive HRE content (65 at%) in the diffusion source leads to severe Tb accumulation on magnet surface, while insufficient HRE content (40 at%) results in formation of incomplete core–shell structure in the deeper regions. This finding challenges the conventional 70 at% HRE: 30 at% auxiliary element diffusion source paradigm, further enhancing Tb utilization efficiency and pro","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"44 7","pages":"Pages 2146-2157"},"PeriodicalIF":9.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148530165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive first-principles analysis on rare earth complex hydrides LiABH6 (A = Sc, Y; B = Fe, Ru, Os): A promising class of hydrogen storage materials","authors":"Asif Hosen,&nbsp;Ebrahim Nemati-Kande,&nbsp;Heider A. Abdulhussein,&nbsp;Ali Akremi,&nbsp;Imed Boukhris","doi":"10.1016/j.jre.2025.09.004","DOIUrl":"10.1016/j.jre.2025.09.004","url":null,"abstract":"<div><div>In this study, the structural, optoelectronic, phonon, thermal, mechanical, and hydrogen storage characteristics of rare earth-based hydrides (REHs) LiABH₆ (A = Sc, Y; B = Fe, Ru, Os) were systematically investigated using the first-principles calculation. The analysis indicates that each of the studied compounds crystallizes in a cubic phase, belonging to the space group <em>F</em><span><math><mrow><mover><mn>4</mn><mo>¯</mo></mover><mn>3</mn></mrow></math></span><em>m</em> (No. 216). Phonon dispersion results confirm the dynamical robustness of the compounds, whereas <em>ab initio</em> molecular dynamics (AIMD) simulations affirm their thermal resilience, showing no signs of structural distortion. The band structure reveals that all REHs conduct as indirect band gap semiconductors, with band gap energies ranging between 3.94 and 4.21 eV as calculated using the hybrid functional approach. Investigation of the optical properties shows that these hydrides exhibit strong absorption in the ultraviolet region, with a distinct red shift in the absorption edge attributed to band gap variations. Furthermore, the thermodynamic properties at various temperatures were examined utilizing the Quasi-Harmonic Debye approach, yielding results consistent with core thermodynamic laws. The computed hydrogen storage capacities for the compounds LiScFeH₆, LiScRuH₆, LiScOsH₆, LiYFeH₆, LiYRuH₆, and LiYOsH₆ are 5.31 wt%, 3.80 wt%, 2.44 wt%, 3.83 wt%, 2.98 wt% and 2.07 wt%, respectively. The findings reveal that LiScFeH₆ emerges as the most favorable candidate for storing H₂, offering the highest capacity among the studied compounds and exceeding the benchmark established by the U.S. Department of Energy (DOE).</div></div>","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"44 7","pages":"Pages 2166-2176"},"PeriodicalIF":9.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148530095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting rare earth extraction efficiency with organophosphorus ligands: A data-driven machine learning approach","authors":"Qihan Zhang,&nbsp;Haitao Wang,&nbsp;Ziyi Liu,&nbsp;Zhaomin Hao,&nbsp;Wuping Liao","doi":"10.1016/j.jre.2025.09.016","DOIUrl":"10.1016/j.jre.2025.09.016","url":null,"abstract":"<div><div>Organophosphorus ligands are widely employed as extractants in industrial rare-earth (RE) separation; however, their design and optimization have largely been guided by empirical methodologies rather than systematic, rational approaches. In this work, we present a data-driven machine learning framework for predicting the distribution ratios (<em>D</em>) of RE elements in extraction processes using various organophosphorus ligands. To support this effort, a curated database comprising over 3500 experimental <em>D</em> measurements was established, encompassing 43 distinct ligands and 16 RE elements (excluding radioactive promethium) under varied extraction conditions. By integrating ligand descriptors, metal ion properties, and extraction parameters, we developed a convolutional neural network (CNN) model that achieves robust performance, with <em>R</em>² values of approximately 0.98 for training and 0.83 for testing. Our analysis further identified key factors – such as aqueous pH, ligand structural fragments, partial charges, metal ionic radii and topological features – that govern extraction behavior and correlate with specific mechanisms. Finally, the predictive capability of model was validated by accurately forecasting the <em>D</em> value of a newly synthesized ligand HA.</div></div>","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"44 7","pages":"Pages 2204-2214"},"PeriodicalIF":9.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148530101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dye-sensitized rare-earth-doped nanoparticles and MOF heterostructures for enhanced NIR-II fluorescence imaging and synergistic photothermal and photodynamic therapy","authors":"Ming Qian,&nbsp;Jiarui Du,&nbsp;Qichuan Jiang,&nbsp;Wei Tao,&nbsp;Jiayi Zhang,&nbsp;Liang Gong","doi":"10.1016/j.jre.2025.09.006","DOIUrl":"10.1016/j.jre.2025.09.006","url":null,"abstract":"<div><div>Early diagnosis and treatment of cancer are key problems for effective cancer therapy. Therefore, the development of multifunctional materials that can integrate imaging and therapeutic functions is of great importance. Lanthanide-doped nanoparticles@metal–organic frameworks (Ln-NPs@MOFs) offer an unprecedented opportunity to address this challenge, by combining the imaging capabilities of rare earth-doped nanoparticles with the photosensitizing properties of MOFs for photodynamic therapy (PDT). Here, we report a near-infrared (NIR) light-responsive nanoparticle based on a zirconium-porphyrin metal–organic framework (PCN-224) for synergistic photothermal and photodynamic therapy. Tetra(4-carboxyphenyl)porphyrin (TCPP) that constitutes the MOF framework serves as a natural photosensitizer, enabling efficient photodynamic therapy through Förster resonance energy transfer (FRET). The dye indocyanine green (ICG) was loaded into the MOF pores to sensitize the Ln nanoparticles, enhancing the upconversion fluorescence by 41 times and the downconversion fluorescence by 5 times, which is beneficial to the biological efficacy for imaging diagnosis. Meanwhile, ICG, a traditional photothermal agent, also imparts photothermal therapy capabilities to the system. Furthermore, the encapsulation of cancer cell membranes not only enhances biocompatibility but also improves the material's targeting towards cancer cells, thereby greatly enhancing the therapeutic effect. This dual-functional material provides a promising platform for the integration of cancer diagnosis and therapy.</div></div>","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"44 7","pages":"Pages 2047-2056"},"PeriodicalIF":9.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147900326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrogen-driven metal-support interaction in Ni-CeO2 catalysts boosting low-temperature CO2 methanation","authors":"Ru Zhao,&nbsp;Siyuan Xu,&nbsp;Junliang Xia,&nbsp;Mingxue Wang,&nbsp;Xiaoyan Han,&nbsp;Yu Xie,&nbsp;Qiulin Zhang,&nbsp;Ping Ning","doi":"10.1016/j.jre.2025.12.019","DOIUrl":"10.1016/j.jre.2025.12.019","url":null,"abstract":"<div><div>Converting CO₂ to CH₄ under mild conditions represents a promising strategy for carbon emission reduction and synthetic natural gas production, yet it remains challenging. In this work, we accelerated low-temperature CO₂ hydrogenation over Ni-CeO₂ catalysts by optimizing metal-support interactions through H₂-driven reconstruction. The catalyst reduced at 400 °C (Ni-CeO₂-400R) achieved 84.3% CO₂ conversion with 100% CH₄ selectivity even at a low temperature of 250 °C. Various <em>in situ</em> spectroscopic characterizations (X-ray photoelectron spectroscopy (XPS), Raman, and diffused reflectance infrared Fourier transform spectroscopy (DRIFTS)) and H₂/D₂ isotopic exchange experiments reveal that the appropriate interaction in Ni-CeO₂ motivates the dispersion of metallic Ni sites and the generation of oxygen vacancies, thereby promoting the activation of H₂ and CO₂ molecules, respectively. Therefore, CO₂ is efficiently adsorbed and converted into reactive intermediates and finally hydrogenated to CH₄ through carbonyl and formate pathways simultaneously. These findings underscore the critical role of tailored metal-support interactions in designing advanced CO₂ hydrogenation catalysts.</div></div>","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"44 7","pages":"Pages 2097-2105"},"PeriodicalIF":9.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148530161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced co-elimination activity of NO and toluene over VmCeOx catalysts by vanadium addition and insight into mutual inhibition effects on activity between toluene oxidation and NO reduction","authors":"Zixiang Sun,&nbsp;Yushi Li,&nbsp;Zhewen Zhang,&nbsp;Xiaoyu Niu,&nbsp;Yujun Zhu","doi":"10.1016/j.jre.2025.07.021","DOIUrl":"10.1016/j.jre.2025.07.021","url":null,"abstract":"<div><div>Simultaneous catalytic elimination of toluene and NO is currently the most economical and promising means to control their emission. But it is also a challenge topic due to the different requirements for the properties of the catalyst in selective catalytic reduction with NH₃ (NH₃-SCR) deNO_<em>x</em> and toluene oxidation reactions. Moreover, the interactions among NH₃, NO and toluene are complex and how to influence the activity is still unclear. In this study, the V_<em>m</em>CeO_<em>x</em> (<em>m</em> = 0.0087–0.097) catalysts for simultaneous NH₃-SCR de-NO_<em>x</em> and toluene oxidation were prepared by co-precipitation and characterized by various methods. The V_0.028CeO_<em>x</em> catalyst exhibits much better co-elimination activity of NO and toluene and excellent H₂O and SO₂ resistance, in which toluene and NO conversion can reach above 90% from 225 to 365 °C. A series of characterizations reveals that the addition of appropriate amount of vanadium (V) can balance the acidity and oxidizing ability of catalyst, achieving the purpose of highly effective co-elimination of toluene and NO. Specially, this paper focuses on the interactions among toluene, NH₃ and NO that affect the co-elimination activity to reveal the formation mechanism of the by-products by means of <em>in situ</em> diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The testing results indicate that toluene can react with NH₃ to form nitrile and amide species, which are not easy to be decomposed and deposited on the surface of the catalyst to occupy the active sites, thus inhibiting the deep oxidation of toluene and the formation of active NH₂ species. In addition, the adsorption and activation of toluene and NO are greatly inhibited by the competition adsorption, and they can form nitrile species. Interestingly, the V_0.028CeO_<em>x</em> catalyst shows a significant inhibitory effect on the formation of nitriles and amide in the coexistence of NH₃, NO and toluene, which may be due to the preferential reaction of NH₃ and NO. This study provides insight into the co-elimination of VOC molecules and NO in the wide activity temperature window over the same catalyst and referential value for the subsequent design of catalysts that eliminate both toluene and NO without the generation of by-product.</div></div>","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"44 7","pages":"Pages 2081-2096"},"PeriodicalIF":9.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148530098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructural evolution and strengthening mechanism of Mg-Gd-Y-Zn-Zr alloy fabricated by wire arc additive manufacturing: Effects of heat treatment on mechanical properties","authors":"Limin Zhang,&nbsp;Dongdong Zhang,&nbsp;Zizheng Zhang,&nbsp;Jiarui Hu,&nbsp;Ke Li,&nbsp;Yunlong Li,&nbsp;Liqin Wang,&nbsp;Zhanyong Zhao,&nbsp;Peikang Bai","doi":"10.1016/j.jre.2025.09.046","DOIUrl":"10.1016/j.jre.2025.09.046","url":null,"abstract":"<div><div>Thin-walled Mg-8.5Gd-2.5Y-1.8Zn-0.5Zr (GWZ932) alloy component was successfully fabricated by the cold metal transfer (CMT) based wire-arc additive manufacturing (WAAM) process. Considering the significant influence of secondary phases on mechanical properties, we regulated the secondary phases through heat treatment. As-deposited sample exhibits the typical layered microstructure with alternating coarse/fine grains, along with a lot of Mg₃(RE,Zn) eutectic phases at grain boundaries (GBs). After solid-solution treatment, these eutectic phases are transformed into coarse X phase at GBs and fine lamellar 14H long period ordered stacking (14H-LPSO) phases in grain interiors. Further peak-aging induces amounts of prismatic β′ phases precipitated in the α-Mg matrix, which produces the strong precipitation hardening effect. Note that prismatic β′ phases are perpendicular to basal 14H-LPSO phase in space, which can form a closed space that blocks dislocation motions more effectively. Thus, peak-aged sample exhibits a high tensile strength of (314 ± 3) MPa and an acceptable ductility of 4.3% ± 0.6%, which outperforms most Mg-Gd-Y series alloys prepared by WAAM reported previously. Our work provides a basis for forming thin-walled Mg-Gd-Y series components with high strength via WAAM process, but the deposition process should be further optimized.</div></div>","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"44 7","pages":"Pages 2227-2238"},"PeriodicalIF":9.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148530102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ce-induced electronic structure reconfiguration in Ni-based heterostructures for accelerated alkaline hydrogen evolution","authors":"Xuejiao Sun,&nbsp;Hongxi Li,&nbsp;Ji Hua,&nbsp;Xiang Ji,&nbsp;Dongmei Li,&nbsp;Zhongzhen Tian,&nbsp;Ying Liu","doi":"10.1016/j.jre.2026.04.033","DOIUrl":"10.1016/j.jre.2026.04.033","url":null,"abstract":"<div><div>This study aimed to develop efficient and stable non-precious metal electrocatalysts for the hydrogen evolution reaction (HER), addressing the limitations of current catalysts such as insufficient activity and high cost. A self-supported CeS/NiS/Ni₃N/SSM electrocatalyst with abundant heterointerfaces was successfully constructed on a stainless steel mesh (SSM) via an electrodeposition combined with high-temperature solid-gas phase sulfidation/nitridation strategy. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses confirm the successful introduction of CeS and the strong electronic interaction among the three phases of CeS, NiS, and Ni₃N. The doping of Ce induces a redistribution of interface charges, forming electron-deficient Ni centers and optimizing the hydrogen adsorption energy. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterizations reveal that the introduction of CeS transforms the smooth agglomerated particles of NiS/Ni₃N into a hierarchical porous structure composed of nanoclusters, significantly increasing the electrochemically active area and constructing clear heterointerfaces, which facilitates the exposure of active sites and mass transfer processes. Density functional theory calculations further indicate that the CeS/NiS/Ni₃N heterostructure exhibits a hydrogen adsorption Gibbs free energy (Δ<em>G</em>_H∗) close to zero (−0.16 eV), significantly superior to that of single components, thereby optimizing the reaction kinetics. The results demonstrate that CeS/NiS/Ni₃N/SSM delivers outstanding HER performance in 1 mol/L KOH, requiring an overpotential of only 73.6 mV to achieve the 10 mA/cm² current density, with a Tafel slope of 87.6 mV/dec, and maintains excellent stability for at least 48 h. This work illustrates that constructing heterointerfaces with simultaneous electronic modulation and structural optimization provides an effective pathway for designing high-performance non-precious metal electrocatalysts.</div></div>","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"44 7","pages":"Pages 2073-2080"},"PeriodicalIF":9.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148530104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient and tunable photoluminescence from Dy3+-doped Cs2NaLuCl6 double perovskites via Sb3+ sensitization","authors":"Guodong Zhang,&nbsp;Yue Lu,&nbsp;Yaning Zhao,&nbsp;Peipei Dang,&nbsp;Hao Suo,&nbsp;Zhijun Wang,&nbsp;Panlai Li","doi":"10.1016/j.jre.2025.07.018","DOIUrl":"10.1016/j.jre.2025.07.018","url":null,"abstract":"<div><div>Incorporating rare-earth (RE³⁺) ions into lead-free halide double perovskites represents a promising strategy for modulating their optical properties through energy transfer mechanisms. In this study, Dy³⁺ ions were successfully incorporated into Cs₂NaLuCl₆:Sb³⁺ double perovskites via a facile hydrothermal method. The synthesized crystals not only exhibit intense blue emission originating from self-trapped excitons (STEs) but also display effective Dy³⁺ characteristic emissions, thereby broadening the emission spectrum from the visible to the near-infrared region. The energy transfer from STEs to Dy³⁺ is confirmed and extends across various RE³⁺ ions. Temperature-dependent photoluminescence spectra reveal insights into the excitation and emission processes, as well as thermal quenching mechanism. Additionally, the characteristic emissions of Dy³⁺ demonstrate varied anti-thermal quenching behaviors, indicating the remarkable thermal stability of the synthesized crystals. The thermally coupled sub-levels of Dy³⁺ ions are employed to develop optical thermometers with notable sensitivity. Finally, the light-emitting diodes fabricated by encapsulating the optimized samples onto commercial chips highlight the great potential of Dy³⁺-doped Cs₂NaLuCl₆:Sb³⁺ materials for photoelectric applications.</div></div>","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"44 7","pages":"Pages 2010-2018"},"PeriodicalIF":9.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147330889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of temperature regulation of complex stability constants in removal of key impurities from lanthanum oxide","authors":"Yuanxuan Yu,&nbsp;Meng Wang,&nbsp;Qingping Zhang,&nbsp;Zongyu Feng,&nbsp;Yang Xu,&nbsp;Guang Yang,&nbsp;Zhiqing Yang","doi":"10.1016/j.jre.2025.05.021","DOIUrl":"10.1016/j.jre.2025.05.021","url":null,"abstract":"<div><div>In the ion-exchange process for separating and purifying rare earth elements, the separation is primarily achieved through the differences in the complexation reactions between the rare earth elements and the eluent. Therefore, enhancing these reaction differences is crucial to improving separation efficiency. In this study, the dissociation constants of ethylene diamine tetraacetic acid (EDTA) at different temperatures were determined by pH potentiometric titration. The speciation evolution of metal-EDTA complexes was elucidated through simulations conducted with Visual MINTEQ, enabling a systematic investigation into the temperature dependence of stability constants for EDTA complexes with La³⁺ and representative impurity metal ions (Ce³⁺, Mg²⁺, Al³⁺, Ca²⁺, Cu²⁺, Zn²⁺). Building upon this, static desorption studies and ion-exchange experiments were conducted to validate the removal of key impurities in lanthanum oxide. Experimental results show that, Mg²⁺ and Ca²⁺ exhibit better selective separation from La³⁺ due to the significant differences in complexation constants. The difference in complexation stabilization constants between La³⁺ and impurity ions reaches the maximum at 30 °C. The temperature primarily enhances the reaction difference in the separation system by modulating the distribution of complex species. Desorption studies indicate that increasing the temperature improves the separation coefficient between La and impurity elements. After optimization, the ion-exchange method achieves a La recovery rate of 84.91 wt% and a total impurity removal rate exceeding 92.50 wt%. Under the optimized elution conditions, an elution process was applied to the real feed solution, yielding a lanthanum oxide product with a relative purity of 99.99991 wt%. This work deepens the understanding of temperature-induced regulation of complexation stability constants and provides a novel approach for ion-exchange purification of rare earth elements.</div></div>","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"44 7","pages":"Pages 2215-2226"},"PeriodicalIF":9.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147901591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}