Solid State Communications最新文献

Magnetic properties of rare earth doped ZnO nanoparticles: A comprehensive study via Magnetization and EPR 稀土掺杂ZnO纳米粒子的磁性能：磁化和EPR综合研究

IF 2.4 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications

Pub Date : 2026-04-01 Epub Date: 2026-02-19 DOI: 10.1016/j.ssc.2026.116373

Rakesh Tiwari , Sujata Borade , Archana Sharma , Santosh Mani

This study presents the synthesis and characterization of rare earth (RE)-doped zinc oxide (ZnO) nanoparticles with an average particle size in the 10 nm range. The resulting nanostructures exhibit the wurtzite phase of ZnO, attributed to their preferential anisotropic growth along the polar c-axis. Upon excitation of the ZnO host within the bandgap region, visible luminescence intensity increases with rising RE³⁺ concentrations. This emission is primarily attributed to various intrinsic and extrinsic defect states within the host lattice. Energy transfer from these defect centers to RE³⁺ dopant sites facilitates characteristic luminescence. Specifically, efficient intra-4f orbital transitions (⁵D₄ → ⁷Fⱼ) of Tb³⁺ ions result in distinctive green and red emissions. Furthermore, modulation of defect states and decay rates of RE³⁺ transitions enables temporal control over the emission profile, allowing for selective generation of red or pure green light. This work highlights the potential of defect engineering via bottom-up synthesis methods to tailor energy transfer dynamics, offering promising avenues for the development of multicolor emission displays and ZnO-based optoelectronic phosphor devices. In addition to their optical applications, RE-doped ZnO nanoparticles exhibit unique physicochemical and biological properties that contribute to sustainable agricultural practices. These nanoparticles enhance plant tolerance to abiotic stresses such as drought, salinity, and heavy metal contamination by boosting antioxidant enzyme activity and immobilizing toxic metals. From a sustainability perspective, their use promotes reduced environmental contamination, improved nutrient use efficiency, and lower dependence on chemical inputs, thereby supporting eco-friendly and resource-efficient agriculture.

本文研究了平均粒径在10 nm范围内的稀土（RE）掺杂氧化锌（ZnO）纳米粒子的合成和表征。所得到的纳米结构表现为ZnO的纤锌矿相，这归因于它们沿极性c轴的优先各向异性生长。当ZnO主体在带隙区激发后，可见光发光强度随RE3+浓度的增加而增加。这种发射主要归因于主晶格内的各种内在和外在缺陷态。从这些缺陷中心到RE3+掺杂点的能量转移促进了特征发光。具体来说，Tb3+离子的有效的4f内轨道跃迁（5D4→7Fⱼ）导致了独特的绿色和红色发射。此外，对RE3+跃迁的缺陷态和衰减率的调制使得能够对发射轮廓进行时间控制，从而允许选择性地产生红光或纯绿光。这项工作强调了缺陷工程的潜力，通过自下而上的合成方法来定制能量传递动力学，为开发多色发射显示器和基于zno的光电荧光粉器件提供了有希望的途径。除了光学应用外，re掺杂ZnO纳米颗粒还具有独特的物理化学和生物特性，有助于可持续农业实践。这些纳米颗粒通过提高抗氧化酶活性和固定有毒金属来增强植物对干旱、盐度和重金属污染等非生物胁迫的耐受性。从可持续发展的角度来看，它们的使用有助于减少环境污染，提高养分利用效率，降低对化学品投入的依赖，从而支持生态友好型和资源节约型农业。

{"title":"Magnetic properties of rare earth doped ZnO nanoparticles: A comprehensive study via Magnetization and EPR","authors":"Rakesh Tiwari , Sujata Borade , Archana Sharma , Santosh Mani","doi":"10.1016/j.ssc.2026.116373","DOIUrl":"10.1016/j.ssc.2026.116373","url":null,"abstract":"<div><div>This study presents the synthesis and characterization of rare earth (RE)-doped zinc oxide (ZnO) nanoparticles with an average particle size in the 10 nm range. The resulting nanostructures exhibit the wurtzite phase of ZnO, attributed to their preferential anisotropic growth along the polar c-axis. Upon excitation of the ZnO host within the bandgap region, visible luminescence intensity increases with rising RE3+ concentrations. This emission is primarily attributed to various intrinsic and extrinsic defect states within the host lattice. Energy transfer from these defect centers to RE3+ dopant sites facilitates characteristic luminescence. Specifically, efficient intra-4f orbital transitions (5D4 → 7Fⱼ) of Tb3+ ions result in distinctive green and red emissions. Furthermore, modulation of defect states and decay rates of RE3+ transitions enables temporal control over the emission profile, allowing for selective generation of red or pure green light. This work highlights the potential of defect engineering via bottom-up synthesis methods to tailor energy transfer dynamics, offering promising avenues for the development of multicolor emission displays and ZnO-based optoelectronic phosphor devices. In addition to their optical applications, RE-doped ZnO nanoparticles exhibit unique physicochemical and biological properties that contribute to sustainable agricultural practices. These nanoparticles enhance plant tolerance to abiotic stresses such as drought, salinity, and heavy metal contamination by boosting antioxidant enzyme activity and immobilizing toxic metals. From a sustainability perspective, their use promotes reduced environmental contamination, improved nutrient use efficiency, and lower dependence on chemical inputs, thereby supporting eco-friendly and resource-efficient agriculture.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"411 ","pages":"Article 116373"},"PeriodicalIF":2.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Structural and low-temperature magnetic properties in Ba2GdBiO6 double-perovskite oxide Ba2GdBiO6双钙钛矿氧化物的结构和低温磁性能

IF 2.4 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications

Pub Date : 2026-04-01 Epub Date: 2026-02-16 DOI: 10.1016/j.ssc.2026.116359

Jiameng Xu, Junmiao Lin, Liyao Zhu, Xijia Chen, Yikun Zhang

The low-temperature magnetocaloric (MC) properties in rare-earth-based materials have been examined intensively which was aimed to search of suitable candidates for magnetic cooling applications. We herein synthesized a single-phased Ba₂GdBiO₆ oxide via a solid-state reaction route and examined its structural, elemental valence states, magnetic and MC properties. Our studies indicated that the Ba₂GdBiO₆ oxide crystallizes in a double perovskite (DP)-type structure with monoclinic C12/m1 space group at room temperature and shows no distinct magnetic ordering above 1.8 K. The constituent elements are homogeneously distributed and presented as expected valence states of Ba²⁺, Gd³⁺, Bi⁵⁺, and O²⁻. Considerable reversible low-temperature MC effect were observed in Ba₂GdBiO₆ DP oxide with maximum magnetic entropy change and relative cooling power/refrigerant capacity as 21.32 J/kgK and 125.55/90.70 J/kg (magnetic field variation of 0-50 kOe), respectively. These identified values of MC parameters in Ba₂GdBiO₆ DP oxide are comparable with those of A₂REMO₆ DP oxides and recently acquired materials with notable low-temperature MC responses, making it considerable for low-temperature cooling applications.

本文对稀土基材料的低温磁热特性进行了深入的研究，旨在寻找适合磁冷却应用的候选材料。本文采用固相法合成了一种单相Ba2GdBiO6氧化物，并对其结构、元素价态、磁性和MC性质进行了研究。我们的研究表明，Ba2GdBiO6氧化物在室温下以单斜C12/m1空间群的双钙钛矿（DP）型结构结晶，在1.8 K以上没有明显的磁有序。组成元素均匀分布，呈现出Ba2+、Gd3+、Bi5+和O2−的预期价态。Ba2GdBiO6 DP氧化物具有明显的可逆低温MC效应，磁熵变化最大值为21.32 J/kgK，相对冷却功率/制冷剂容量为125.55/90.70 J/kg（磁场变化0-50 kOe）。这些在Ba2GdBiO6 DP氧化物中的MC参数鉴定值与A2REMO6 DP氧化物和最近获得的具有显著低温MC响应的材料相当，使其具有相当的低温冷却应用价值。

{"title":"Structural and low-temperature magnetic properties in Ba2GdBiO6 double-perovskite oxide","authors":"Jiameng Xu, Junmiao Lin, Liyao Zhu, Xijia Chen, Yikun Zhang","doi":"10.1016/j.ssc.2026.116359","DOIUrl":"10.1016/j.ssc.2026.116359","url":null,"abstract":"<div><div>The low-temperature magnetocaloric (MC) properties in rare-earth-based materials have been examined intensively which was aimed to search of suitable candidates for magnetic cooling applications. We herein synthesized a single-phased Ba2GdBiO6 oxide via a solid-state reaction route and examined its structural, elemental valence states, magnetic and MC properties. Our studies indicated that the Ba2GdBiO6 oxide crystallizes in a double perovskite (DP)-type structure with monoclinic C12/m1 space group at room temperature and shows no distinct magnetic ordering above 1.8 K. The constituent elements are homogeneously distributed and presented as expected valence states of Ba2+, Gd3+, Bi5+, and O2−. Considerable reversible low-temperature MC effect were observed in Ba2GdBiO6 DP oxide with maximum magnetic entropy change and relative cooling power/refrigerant capacity as 21.32 J/kgK and 125.55/90.70 J/kg (magnetic field variation of 0-50 kOe), respectively. These identified values of MC parameters in Ba2GdBiO6 DP oxide are comparable with those of A2REMO6 DP oxides and recently acquired materials with notable low-temperature MC responses, making it considerable for low-temperature cooling applications.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"411 ","pages":"Article 116359"},"PeriodicalIF":2.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Emerging optoelectronic and photocatalytic characteristics of two-dimensional BiSF/GaSe van der Waals heterostructure 二维BiSF/GaSe范德华异质结构新出现的光电和光催化特性

IF 2.4 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications

Pub Date : 2026-04-01 Epub Date: 2026-02-18 DOI: 10.1016/j.ssc.2026.116371

Riddhi Desai, Yashasvi Naik, Disha Mehta, I.B. Patel

Formation of van der Waals heterostructures (vdWH) with superior properties has gained considerable attention in optoelectronic and photocatalytic applications. In present research, van der Waals heterostructure BiSF/GaSe has been investigated using first-principles calculations. The monolayers of BiSF and GaSe have been examined first and the outcome is compared with the vdWH. The possible stacking was assessed through first-principles calculations. The thermodynamic stability, electronic band structure, and optical response were thoroughly examined. The carrier migration from GaSe to the BiSF monolayer was verified through CDD. Based on band alignment analysis, Type-II indirect band gap has been confirmed. The optical properties show that from the absorption coefficient, the heterostructure shows higher light-absorption capacity than BiSF and GaSe monolayers, expanding from the visible to UV range, which shows its possible application in optoelectronic and photocatalytic fields.

具有优异性能的范德华异质结构（vdWH）的形成在光电和光催化领域得到了广泛的关注。本研究利用第一性原理计算研究了van der Waals异质结构BiSF/GaSe。首先研究了BiSF和GaSe的单层结构，并与vdWH进行了比较。通过第一性原理计算评估了可能的叠加。研究了该材料的热力学稳定性、电子能带结构和光学响应。通过CDD验证了载流子从GaSe到BiSF单层的迁移。基于带向分析，确定了ii型间接带隙。光学性质表明，从吸收系数来看，该异质结构比BiSF和GaSe单层具有更高的光吸收能力，从可见光范围扩展到紫外范围，显示了其在光电和光催化领域的可能应用。

引用次数: 0

Dynamic and tunable ultra-narrowband terahertz absorber with the phase transition characteristics of VO2 具有VO2相变特性的动态可调谐超窄带太赫兹吸收体

IF 2.4 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications

Pub Date : 2026-04-01 Epub Date: 2026-02-19 DOI: 10.1016/j.ssc.2026.116368

Chen Jinjiang , Zhe Pan , Jun Zhu

Currently, conventional terahertz sensors face significant challenges in achieving high sensitivity and resolution when detecting minute refractive index variations in biological and chemical samples. In response to this challenge, we propose an ultrasensitive, multifunctional, and tunable ultra-narrowband terahertz absorber. The device is based on a metal–insulator–metal (MIM) sandwich structure, comprising a top patterned graphene/vanadium dioxide (VO₂) composite layer, an intermediate dielectric spacer, and a bottom metallic reflector. Dynamic and tunable ultra-narrowband terahertz absorption is realized through the electrostatic modulation of graphene's Fermi level combined with thermoelectric control of the metal–insulator phase transition in VO₂. Simulation results demonstrate near-perfect ultra-narrowband absorption (with a full width at half maximum of approximately 0.1 THz) at frequencies around 0.82 THz and 1.43 THz. The absorption peak frequency exhibits a pronounced blue shift upon tuning the chemical potential of graphene, while modulation of VO2 conductivity enables both frequency shifting and amplitude control of the absorption. Furthermore, the absorber exhibits wide-angle insensitivity, maintaining stable absorption performance under TE-polarized incidence angles from 0° to 50°, alongside exceptional refractive index sensing sensitivity. This design effectively integrates the electrical tunability of graphene with the phase transition characteristics of VO₂, providing an innovative “wide-angle stable, multi-field coupled tunable” device solution for applications in terahertz intelligent communication, biomedical detection, and dynamic spectral regulation.

目前，传统的太赫兹传感器在检测生物和化学样品的微小折射率变化时，在实现高灵敏度和高分辨率方面面临着重大挑战。为了应对这一挑战，我们提出了一种超灵敏、多功能、可调谐的超窄带太赫兹吸收器。该装置基于金属-绝缘体-金属（MIM）夹层结构，包括顶部图案石墨烯/二氧化钒（VO2）复合层，中间介电间隔层和底部金属反射器。通过石墨烯费米能级的静电调制结合VO2中金属-绝缘体相变的热电控制，实现了动态可调谐的超窄带太赫兹吸收。仿真结果表明，在0.82 THz和1.43 THz附近的频率处，超窄带吸收接近完美（半宽约为0.1 THz）。在调整石墨烯的化学势后，吸收峰频率表现出明显的蓝移，而VO2电导率的调制可以实现吸收的频移和幅度控制。此外，吸收剂具有广角不灵敏度，在te偏振入射角从0°到50°范围内保持稳定的吸收性能，同时具有优异的折射率传感灵敏度。本设计将石墨烯的电可调谐性与VO2的相变特性有效地结合在一起，为太赫兹智能通信、生物医学检测和动态光谱调节等领域提供了一种创新的“广角稳定、多场耦合可调谐”器件解决方案。

{"title":"Dynamic and tunable ultra-narrowband terahertz absorber with the phase transition characteristics of VO2","authors":"Chen Jinjiang , Zhe Pan , Jun Zhu","doi":"10.1016/j.ssc.2026.116368","DOIUrl":"10.1016/j.ssc.2026.116368","url":null,"abstract":"<div><div>Currently, conventional terahertz sensors face significant challenges in achieving high sensitivity and resolution when detecting minute refractive index variations in biological and chemical samples. In response to this challenge, we propose an ultrasensitive, multifunctional, and tunable ultra-narrowband terahertz absorber. The device is based on a metal–insulator–metal (MIM) sandwich structure, comprising a top patterned graphene/vanadium dioxide (VO2) composite layer, an intermediate dielectric spacer, and a bottom metallic reflector. Dynamic and tunable ultra-narrowband terahertz absorption is realized through the electrostatic modulation of graphene's Fermi level combined with thermoelectric control of the metal–insulator phase transition in VO2. Simulation results demonstrate near-perfect ultra-narrowband absorption (with a full width at half maximum of approximately 0.1 THz) at frequencies around 0.82 THz and 1.43 THz. The absorption peak frequency exhibits a pronounced blue shift upon tuning the chemical potential of graphene, while modulation of VO2 conductivity enables both frequency shifting and amplitude control of the absorption. Furthermore, the absorber exhibits wide-angle insensitivity, maintaining stable absorption performance under TE-polarized incidence angles from 0° to 50°, alongside exceptional refractive index sensing sensitivity. This design effectively integrates the electrical tunability of graphene with the phase transition characteristics of VO2, providing an innovative “wide-angle stable, multi-field coupled tunable” device solution for applications in terahertz intelligent communication, biomedical detection, and dynamic spectral regulation.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"411 ","pages":"Article 116368"},"PeriodicalIF":2.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Designing stable bromide perovskites for energy conversion: d-orbital engineering and molecular dynamics study of K2MBr6 (M = Sn, Ti, Pd, Pt) 设计用于能量转换的稳定溴化钙钛矿：K2MBr6 （M = Sn, Ti, Pd, Pt）的d轨道工程和分子动力学研究

IF 2.4 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications

Pub Date : 2026-04-01 Epub Date: 2026-02-23 DOI: 10.1016/j.ssc.2026.116381

Mohamed El Amine El Goutni , Hela Ferjani , Mohammed Batouche , Taieb Seddik

Lead-free vacancy-ordered double perovskites K₂MBr₆ (M = Sn, Ti, Pd, Pt) were systematically investigated using density functional theory (DFT) to assess their structural stability, electronic behavior, optical activity, and photocatalytic potential for energy-conversion applications. Structural optimization using the WC-GGA functional confirms that all compounds crystallize in the cubic Fm-3m phase with negative formation energies, dynamically stable phonon spectra, and robust thermal behavior supported by ab-initio molecular dynamics simulations at 300 K. Electronic properties obtained using the TB-mBJ potential with spin–orbit coupling reveal a transition from direct band gaps for K₂SnBr₆ and K₂TiBr₆ (Γ→Γ) to indirect band gaps for K₂PdBr₆ and K₂PtBr₆ (X→X), reflecting the influence of d-orbital contributions across the series. Optical calculations indicate strong absorption coefficients in the visible region, linked to Br-p and M-d electronic transitions. Mechanical analysis confirms elastic stability and moderate ductility for all compositions. Photocatalytic feasibility was evaluated using absolute band-edge positions derived from the Mulliken electronegativity model, showing that all compounds possess sufficiently high VBM levels to drive the oxygen evolution reaction, while their CBM positions lie above the H⁺/H₂ reduction potential, indicating that they function as oxidation-active semiconductors suitable for photoanodes or Z-scheme configurations. These results position K₂MBr₆ perovskites as promising lead-free materials for optoelectronic and photocatalytic applications, with tunable properties governed by d-orbital engineering at the B-site cation.

利用密度泛函理论（DFT）对无铅空位有序双钙钛矿K2MBr6 （M = Sn, Ti, Pd, Pt）进行了系统的研究，以评估其结构稳定性、电子行为、光学活性和光催化潜力在能量转换中的应用。使用WC-GGA功能的结构优化证实，所有化合物都在立方Fm-3m相中结晶，具有负的形成能，动态稳定的声子谱，以及在300 K的ab-initio分子动力学模拟支持的强大热行为。利用自旋-轨道耦合的TB-mBJ势获得的电子性质揭示了从K2SnBr6和K2TiBr6的直接带隙（Γ→Γ）到K2PdBr6和K2PtBr6的间接带隙（X→X）的转变，反映了d轨道对整个系列的影响。光学计算表明在可见光区有很强的吸收系数，与Br-p和M-d电子跃迁有关。力学分析证实了所有组合物的弹性稳定性和中等延展性。利用Mulliken电负性模型得出的绝对带边位置来评估光催化的可行性，表明所有化合物都具有足够高的VBM水平来驱动析氧反应，而它们的CBM位置位于H+/H2还原电位之上，表明它们是适合于光阳极或z方案配置的氧化活性半导体。这些结果将K2MBr6钙钛矿定位为光电子和光催化应用的有前途的无铅材料，具有可调的性质，由b位阳离子的d轨道工程控制。

{"title":"Designing stable bromide perovskites for energy conversion: d-orbital engineering and molecular dynamics study of K2MBr6 (M = Sn, Ti, Pd, Pt)","authors":"Mohamed El Amine El Goutni , Hela Ferjani , Mohammed Batouche , Taieb Seddik","doi":"10.1016/j.ssc.2026.116381","DOIUrl":"10.1016/j.ssc.2026.116381","url":null,"abstract":"<div><div>Lead-free vacancy-ordered double perovskites K2MBr6 (M = Sn, Ti, Pd, Pt) were systematically investigated using density functional theory (DFT) to assess their structural stability, electronic behavior, optical activity, and photocatalytic potential for energy-conversion applications. Structural optimization using the WC-GGA functional confirms that all compounds crystallize in the cubic Fm-3m phase with negative formation energies, dynamically stable phonon spectra, and robust thermal behavior supported by ab-initio molecular dynamics simulations at 300 K. Electronic properties obtained using the TB-mBJ potential with spin–orbit coupling reveal a transition from direct band gaps for K2SnBr6 and K2TiBr6 (Γ→Γ) to indirect band gaps for K2PdBr6 and K2PtBr6 (X→X), reflecting the influence of d-orbital contributions across the series. Optical calculations indicate strong absorption coefficients in the visible region, linked to Br-p and M-d electronic transitions. Mechanical analysis confirms elastic stability and moderate ductility for all compositions. Photocatalytic feasibility was evaluated using absolute band-edge positions derived from the Mulliken electronegativity model, showing that all compounds possess sufficiently high VBM levels to drive the oxygen evolution reaction, while their CBM positions lie above the H+/H2 reduction potential, indicating that they function as oxidation-active semiconductors suitable for photoanodes or Z-scheme configurations. These results position K2MBr6 perovskites as promising lead-free materials for optoelectronic and photocatalytic applications, with tunable properties governed by d-orbital engineering at the B-site cation.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"411 ","pages":"Article 116381"},"PeriodicalIF":2.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Irradiation induces structural and valence state conversion of Sm-doped lithium borate glass 辐照诱导掺钐硼酸锂玻璃的结构态和价态转变

IF 2.4 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications

Pub Date : 2026-04-01 Epub Date: 2026-02-21 DOI: 10.1016/j.ssc.2026.116378

Hanan Ali , A.M. Saad , Y. Badr , M.M. Elokr , Alaa E. Giba

The conversion between the two valence states of Sm ion, 3+ and 2+, attracts great attention thanks to its crucial role in spectral Hole Burning and the associated applications ranging from spectroscopy to quantum computing and data storage. This work reports on the influence of gamma (γ) irradiation on the conversion of Sm³⁺ to Sm²⁺. Fourier Transform Infrared Spectroscopy (FTIR) and Electron Spin Resonance (ESR) analyses, after irradiation, point to microstructural change that exhibits partial transformation of BO₃ to BO₄ (distorted BO₃) of borate units. This local environmental modification is likely favorable for conversion the valence state of Sm from 3+ to 2+. In addition, the photoluminescence (PL) measurement evidences such valence state conversion after irradiation. The PL spectral features confirm the emission lines related to the converted valence state version (Sm²⁺). The conversion mechanism is attributed to the partial transformation of BO₃ to BO₄ (distorted BO₃) as a result of irradiation interaction. Thus, as a particular case, one sample has been exposed to neutron irradiation in order to induce strong microstructure distortion. As a consequence, the corresponding PL measurement reveals a significant conversion ratio to Sm²⁺. This emphasizes on the usage of the PL as a significant non-destructive tool to probe the valence state conversion. These findings could also provide a considerable approach to understand the physics behind such conversion process.

钐离子3+和2+两个价态之间的转换，由于其在光谱烧洞及其相关应用（从光谱学到量子计算和数据存储）中的重要作用而受到广泛关注。本文报道了γ (γ)辐照对Sm3+转化为Sm2+的影响。傅里叶变换红外光谱（FTIR）和电子自旋共振（ESR）分析表明，辐照后硼酸盐单元的微观结构发生变化，BO3部分转变为BO4（畸变BO3）。这种局部环境的改变可能有利于Sm从3+价态转化为2+价态。此外，光致发光（PL）测量也证实了辐照后的价态转换。PL光谱特征证实了与转换价态版本（Sm2+）相关的发射线。该转化机制归因于辐照相互作用导致BO3部分转化为BO4（畸变BO3）。因此，作为一种特殊情况，一个样品已暴露于中子辐照，以诱导强烈的微观结构畸变。因此，相应的PL测量揭示了到Sm2+的显着转化率。这强调了PL作为探测价态转换的重要非破坏性工具的使用。这些发现也可以为理解这种转换过程背后的物理原理提供一个相当重要的方法。

{"title":"Irradiation induces structural and valence state conversion of Sm-doped lithium borate glass","authors":"Hanan Ali , A.M. Saad , Y. Badr , M.M. Elokr , Alaa E. Giba","doi":"10.1016/j.ssc.2026.116378","DOIUrl":"10.1016/j.ssc.2026.116378","url":null,"abstract":"<div><div>The conversion between the two valence states of Sm ion, 3+ and 2+, attracts great attention thanks to its crucial role in spectral Hole Burning and the associated applications ranging from spectroscopy to quantum computing and data storage. This work reports on the influence of gamma (γ) irradiation on the conversion of Sm3+ to Sm2+. Fourier Transform Infrared Spectroscopy (FTIR) and Electron Spin Resonance (ESR) analyses, after irradiation, point to microstructural change that exhibits partial transformation of BO3 to BO4 (distorted BO3) of borate units. This local environmental modification is likely favorable for conversion the valence state of Sm from 3+ to 2+. In addition, the photoluminescence (PL) measurement evidences such valence state conversion after irradiation. The PL spectral features confirm the emission lines related to the converted valence state version (Sm2+). The conversion mechanism is attributed to the partial transformation of BO3 to BO4 (distorted BO3) as a result of irradiation interaction. Thus, as a particular case, one sample has been exposed to neutron irradiation in order to induce strong microstructure distortion. As a consequence, the corresponding PL measurement reveals a significant conversion ratio to Sm2+. This emphasizes on the usage of the PL as a significant non-destructive tool to probe the valence state conversion. These findings could also provide a considerable approach to understand the physics behind such conversion process.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"411 ","pages":"Article 116378"},"PeriodicalIF":2.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Smart optimization of rare-earth-based perovskite solar cells using machine learning approaches 利用机器学习方法对稀土钙钛矿太阳能电池进行智能优化

IF 2.4 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications

Pub Date : 2026-04-01 Epub Date: 2026-02-24 DOI: 10.1016/j.ssc.2026.116380

Ranadip Kundu

Perovskite solar cells (PSCs) have attracted considerable attention due to their high power conversion efficiency (PCE), low fabrication cost, and lightweight nature; however, concerns regarding lead toxicity and long-term stability hinder large-scale deployment. In this work, a lead-free oxide perovskite, La₀.₅Ce₀.₅Fe₀.₉Cd₀.₁O₃ (LCFCO), is proposed and systematically investigated as a novel absorber material using the SCAPS-1D simulation framework. Partial substitution of Fe with Cd enables bandgap tuning to approximately 2.0 eV, enhancing optical absorption while maintaining structural robustness. The optimized device architecture consists of ITO/TiO₂/LCFCO/NiO, where TiO₂ and NiO serve as stable electron and hole transport layers with favourable energy-level alignment. Comprehensive optimization was performed by varying absorber thickness, doping concentration, intrinsic defect density, interface properties, and resistive losses. The optimal absorber parameters were identified as a thickness of 0.5 μm, acceptor density of 1 × 10¹⁵ cm⁻³, and defect density of 1 × 10¹³ cm⁻³, yielding a maximum PCE of 19.51% under standard AM1.5G illumination. Key photovoltaic parameters, including J_SC, V_OC, FF, and PCE, were systematically analysed along with temperature and resistance effects. Furthermore, a machine-learning-assisted optimization strategy based on a Random Forest regressor was employed to validate simulation trends and identify dominant performance drivers, achieving a predictive accuracy of approximately 96%. The results highlight the strong potential of LCFCO as an environmentally benign absorber and demonstrate the effectiveness of combining device simulation with machine learning for accelerating the design of sustainable PSCs.

钙钛矿太阳能电池（PSCs）因其高功率转换效率（PCE）、低制造成本和轻量化而受到广泛关注；然而，对铅毒性和长期稳定性的担忧阻碍了大规模部署。在这项工作中，提出了一种无铅氧化物钙钛矿La0.5Ce0.5Fe0.9Cd0.1O3 (LCFCO)，并使用SCAPS-1D模拟框架对其作为新型吸收材料进行了系统研究。用Cd部分取代Fe可以使带隙调谐到大约2.0 eV，在保持结构稳健性的同时增强光吸收。优化后的器件结构由ITO/TiO2/LCFCO/NiO组成，其中TiO2和NiO作为稳定的电子和空穴传输层，具有良好的能级排列。通过改变吸收剂厚度、掺杂浓度、本征缺陷密度、界面性能和电阻损耗进行了综合优化。在标准AM1.5G照明下，最佳吸收层厚度为0.5 μm，受体密度为1 × 1015 cm−3，缺陷密度为1 × 1013 cm−3，最大PCE为19.51%。系统分析了JSC、VOC、FF和PCE等关键光伏参数以及温度和电阻效应。此外，采用基于随机森林回归器的机器学习辅助优化策略来验证模拟趋势并识别主要性能驱动因素，预测精度约为96%。研究结果强调了LCFCO作为一种环境友好型吸收剂的强大潜力，并证明了将设备模拟与机器学习相结合以加速可持续psc设计的有效性。

{"title":"Smart optimization of rare-earth-based perovskite solar cells using machine learning approaches","authors":"Ranadip Kundu","doi":"10.1016/j.ssc.2026.116380","DOIUrl":"10.1016/j.ssc.2026.116380","url":null,"abstract":"<div><div>Perovskite solar cells (PSCs) have attracted considerable attention due to their high power conversion efficiency (PCE), low fabrication cost, and lightweight nature; however, concerns regarding lead toxicity and long-term stability hinder large-scale deployment. In this work, a lead-free oxide perovskite, La0.5Ce0.5Fe0.9Cd0.1O3 (LCFCO), is proposed and systematically investigated as a novel absorber material using the SCAPS-1D simulation framework. Partial substitution of Fe with Cd enables bandgap tuning to approximately 2.0 eV, enhancing optical absorption while maintaining structural robustness. The optimized device architecture consists of ITO/TiO2/LCFCO/NiO, where TiO2 and NiO serve as stable electron and hole transport layers with favourable energy-level alignment. Comprehensive optimization was performed by varying absorber thickness, doping concentration, intrinsic defect density, interface properties, and resistive losses. The optimal absorber parameters were identified as a thickness of 0.5 μm, acceptor density of 1 × 1015 cm−3, and defect density of 1 × 1013 cm−3, yielding a maximum PCE of 19.51% under standard AM1.5G illumination. Key photovoltaic parameters, including JSC, VOC, FF, and PCE, were systematically analysed along with temperature and resistance effects. Furthermore, a machine-learning-assisted optimization strategy based on a Random Forest regressor was employed to validate simulation trends and identify dominant performance drivers, achieving a predictive accuracy of approximately 96%. The results highlight the strong potential of LCFCO as an environmentally benign absorber and demonstrate the effectiveness of combining device simulation with machine learning for accelerating the design of sustainable PSCs.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"411 ","pages":"Article 116380"},"PeriodicalIF":2.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigations of transition metal-doped GeSe/GeTe monolayers: Electronic structure and optical properties 过渡金属掺杂GeSe/GeTe单层膜的研究：电子结构和光学性质

IF 2.4 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications

Pub Date : 2026-04-01 Epub Date: 2026-02-26 DOI: 10.1016/j.ssc.2026.116383

Zicheng Zhu , Yingying Zhao , Xianxin Deng , Jie Guo , Baoxue Li

In this work, first-principles calculations based on density functional theory (DFT) were employed to systematically investigate the geometric structures, electronic properties, and optical characteristics of α-GeSe and α-GeTe monolayers. Electronic structure analysis reveals that GeSe exhibits a direct bandgap of about 1.15 eV at the Γ point, whereas GeTe possesses an indirect bandgap of approximately 0.87 eV, making it more favorable for infrared optoelectronic devices. Upon 3d transition metals doping, strong p–d hybridization between transition-metal (TM) 3d and host p orbitals introduces localized impurity states near the Fermi level, resulting in tunable magnetic and electronic properties. V and Cr dopants in GeTe induce spin splitting and metallic or half-metallic behavior, while Fe and Co dopants maintain metallicity with varied spin polarization strength. Comparatively, GeSe shows more localized 3d states and stronger magnetic moments due to weaker p–d coupling. Bader charge analysis reveals electron transfer from Ge and TM atoms to Se/Te atoms, more pronounced in GeSe, indicating higher ionicity and stronger electronic correlation. Overall, transition-metal doping effectively modulates the band structure, conductivity, and spin polarization of GeSe and GeTe, enabling controllable semiconductor-to-metal transitions. These results provide theoretical insight into designing Ge–VIA two-dimensional materials for spintronic and optoelectronic applications.

本文采用基于密度泛函理论（DFT）的第一性原理计算方法，系统地研究了α-GeSe和α-GeTe单层的几何结构、电子性质和光学特性。电子结构分析表明，GeSe在Γ点处的直接带隙约为1.15 eV，而GeTe在Γ点处的间接带隙约为0.87 eV，更有利于红外光电器件的应用。在3d过渡金属掺杂后，过渡金属（TM） 3d和主p轨道之间的强p - d杂化在费米能级附近引入了局域杂质态，导致磁性和电子性质可调谐。在GeTe中，V和Cr掺杂引起自旋分裂和金属或半金属行为，而Fe和Co掺杂在不同的自旋极化强度下保持金属丰度。相比之下，由于p-d耦合较弱，GeSe表现出更多的局域三维态和更强的磁矩。Bader电荷分析显示电子从Ge和TM原子转移到Se/Te原子，在GeSe中更明显，表明离子性更高，电子相关性更强。总的来说，过渡金属掺杂有效地调节了GeSe和GeTe的能带结构、电导率和自旋极化，实现了可控的半导体到金属的转变。这些结果为设计用于自旋电子和光电子应用的Ge-VIA二维材料提供了理论见解。

{"title":"Investigations of transition metal-doped GeSe/GeTe monolayers: Electronic structure and optical properties","authors":"Zicheng Zhu , Yingying Zhao , Xianxin Deng , Jie Guo , Baoxue Li","doi":"10.1016/j.ssc.2026.116383","DOIUrl":"10.1016/j.ssc.2026.116383","url":null,"abstract":"<div><div>In this work, first-principles calculations based on density functional theory (DFT) were employed to systematically investigate the geometric structures, electronic properties, and optical characteristics of α-GeSe and α-GeTe monolayers. Electronic structure analysis reveals that GeSe exhibits a direct bandgap of about 1.15 eV at the Γ point, whereas GeTe possesses an indirect bandgap of approximately 0.87 eV, making it more favorable for infrared optoelectronic devices. Upon 3d transition metals doping, strong p–d hybridization between transition-metal (TM) 3d and host p orbitals introduces localized impurity states near the Fermi level, resulting in tunable magnetic and electronic properties. V and Cr dopants in GeTe induce spin splitting and metallic or half-metallic behavior, while Fe and Co dopants maintain metallicity with varied spin polarization strength. Comparatively, GeSe shows more localized 3d states and stronger magnetic moments due to weaker p–d coupling. Bader charge analysis reveals electron transfer from Ge and TM atoms to Se/Te atoms, more pronounced in GeSe, indicating higher ionicity and stronger electronic correlation. Overall, transition-metal doping effectively modulates the band structure, conductivity, and spin polarization of GeSe and GeTe, enabling controllable semiconductor-to-metal transitions. These results provide theoretical insight into designing Ge–VIA two-dimensional materials for spintronic and optoelectronic applications.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"411 ","pages":"Article 116383"},"PeriodicalIF":2.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electric field induced paraelectric-to- paraelectric phase transformations in Y2O3-Hf0.5Zr0.5O2 ceramics 电场诱导Y2O3-Hf0.5Zr0.5O2陶瓷的对电相变

IF 2.4 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications

Pub Date : 2026-04-01 Epub Date: 2026-02-13 DOI: 10.1016/j.ssc.2026.116361

Amit Kumar , Andy Fitch , Ajay Kumar Kalyani

This study presents an in-depth analysis of the structural behavior of polycrystalline Y₂O₃-Hf_0.5Zr_0.5O₂ ceramics under the influence of an electric field, exploiting high-resolution powder synchrotron X-ray diffraction. The samples were subjected to a novel powder poling method. The experimental results reveal a phase transformation within the material, transitioning from a paraelectric monoclinic phase to a paraelectric cubic phase. Detailed structural analysis suggests, this transformation appears to proceed through an intermediate orthorhombic (Pbcn) phase. The phase transition appears to be primarily influenced by the mismatch in dielectric permittivity (ε or χ) between the different phases and polymorphic phase boundary region, coupled with the presence of oxygen vacancies.

本研究利用高分辨率粉末同步x射线衍射技术，深入分析了多晶Y2O3-Hf0.5Zr0.5O2陶瓷在电场作用下的结构行为。对样品进行了一种新的粉末研磨方法。实验结果表明，材料内部发生了相变，从准电单斜相转变为准电立方相。详细的结构分析表明，这种转变似乎是通过中间正交相（Pbcn）进行的。相变似乎主要受不同相之间介电常数（ε或χ）的不匹配和多晶相边界区域以及氧空位的存在的影响。

引用次数: 0

Copper valence control enables stable lead-free Cs3Cu2Cl5 for white light-emitting diodes 铜价控制使稳定的无铅Cs3Cu2Cl5白光发光二极管

IF 2.4 4区物理与天体物理 Q3 PHYSICS, CONDENSED MATTER

Solid State Communications

Pub Date : 2026-04-01 Epub Date: 2026-02-27 DOI: 10.1016/j.ssc.2026.116388

Gibaek Lee , Haedam Jin , Dohun Baek , Jeongbeom Cha , Suyeong Jo , Tae Oh Yoon , Min Kim

Lead toxicity limits the deployment of metal halide emitters in solid-state lighting. Lead-free copper halides, particularly zero-dimensional Cs₃Cu₂Cl₅, offer bright self-trapped exciton emission, yet achieving high efficiency and stability remains challenging. Here, we demonstrate that the copper precursor valence state is a decisive control parameter. Cs₃Cu₂Cl₅ nanocrystals synthesized using monovalent CuCl exhibit markedly superior phase purity, photoluminescence quantum yield, and ambient stability compared to those from divalent CuCl₂. Cu ⁺ -derived nanocrystals suppress Cu²⁺-induced nonradiative trap states, enabling robust green emission and functional electroluminescence in light-emitting diode (LED) devices with intrinsically broadband emission. These findings establish monovalent-copper synthesis as an effective route toward efficient, stable, lead-free emitters.

铅的毒性限制了金属卤化物发射器在固态照明中的应用。无铅卤化铜，特别是零维Cs3Cu2Cl5，提供明亮的自捕获激子发射，但实现高效率和稳定性仍然具有挑战性。在这里，我们证明了铜前驱体价态是一个决定性的控制参数。与二价CuCl2合成的Cs3Cu2Cl5纳米晶体相比，用一价CuCl2合成的Cs3Cu2Cl5纳米晶体具有明显更高的相纯度、光致发光量子产率和环境稳定性。Cu + 衍生的纳米晶体抑制Cu2+诱导的非辐射阱态，使具有固有宽带发射的发光二极管（LED）器件具有强大的绿色发射和功能电致发光。这些发现确立了一价铜合成是通往高效、稳定、无铅发射体的有效途径。

引用次数: 0