BNT-based energy storage dielectric material is a new type of multifunctional material with environmental friendliness, high energy storage density, and excellent temperature stability. It is a research hotspot where different components are introduced into BNT-based ceramics to obtain ceramic materials with high energy storage density. In this study, 0.94Bi0.5Na0.5TiO3-0.06BaTiO3 (BNBT) was selected as the substrate and doped with La2/3ZrO3 (LZ). Through the modification of La3+/Zr4+ at A/B sites, wider optical bandgap and finer grains with exceptionally large electrical breakdown strength and relatively strong relaxation behaviors in the appropriate range were obtained. Ultimately, an ultra-high energy storage density of 6.48 J/cm3 was attained at 480 kV/cm with a La2/3ZrO3 concentration of 0.07 mol%. In addition, the BNBT-LZ ceramics exhibited a good frequency-stabilized dynamic range (Wrec = 3.29 ± 6.7 % J/cm³, 10–200 Hz) and temperature stability (Wrec = 3.63 ± 9.9 % J/cm³, 20–160 °C), together with excellent charge-discharge performance(t0.9 = 3.36 μs). All these characteristics demonstrate that the modification of BNT-based ceramics by La3+/Zr4+ has a significant effect on the energy storage density. The results show that the BNBT-LZ system can be used as a promising dielectric material for high energy storage density capacitors.
{"title":"Study on structure and electrical properties of BNBT-La2/3ZrO3 ceramic","authors":"Jinhong He , Yunxin Wei , Qin Feng , Jiejie Qin , Yuan Tian , Yanpei Tang , Zhenyong Cen , Changlai Yuan , Nengneng Luo","doi":"10.1016/j.jpcs.2024.112483","DOIUrl":"10.1016/j.jpcs.2024.112483","url":null,"abstract":"<div><div>BNT-based energy storage dielectric material is a new type of multifunctional material with environmental friendliness, high energy storage density, and excellent temperature stability. It is a research hotspot where different components are introduced into BNT-based ceramics to obtain ceramic materials with high energy storage density. In this study, 0.94Bi<sub>0.5</sub>Na<sub>0.5</sub>TiO<sub>3</sub>-0.06BaTiO<sub>3</sub> (BNBT) was selected as the substrate and doped with La<sub>2/3</sub>ZrO<sub>3</sub> (LZ). Through the modification of La<sup>3+</sup>/Zr<sup>4+</sup> at A/B sites, wider optical bandgap and finer grains with exceptionally large electrical breakdown strength and relatively strong relaxation behaviors in the appropriate range were obtained. Ultimately, an ultra-high energy storage density of 6.48 J/cm<sup>3</sup> was attained at 480 kV/cm with a La<sub>2/3</sub>ZrO<sub>3</sub> concentration of 0.07 mol%. In addition, the BNBT-LZ ceramics exhibited a good frequency-stabilized dynamic range (<em>W</em><sub>rec</sub> = 3.29 ± 6.7 % J/cm³, 10–200 Hz) and temperature stability (<em>W</em><sub>rec</sub> = 3.63 ± 9.9 % J/cm³, 20–160 °C), together with excellent charge-discharge performance(<em>t</em><sub>0.9</sub> = 3.36 μs). All these characteristics demonstrate that the modification of BNT-based ceramics by La<sup>3+</sup>/Zr<sup>4+</sup> has a significant effect on the energy storage density. The results show that the BNBT-LZ system can be used as a promising dielectric material for high energy storage density capacitors.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"198 ","pages":"Article 112483"},"PeriodicalIF":4.3,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper demonstrates a numerical study on a novel triple absorber layer-based perovskite photovoltaic cell incorporating Cs3Bi2I9, which offers a relatively high bandgap (2.03 eV) along with superlative thermal stability. Combining it with CsSnGeI3 & CsSnI3 led to enhanced power conversion efficiency in the studied structures. The preliminary simulation performed for the cell configuration, FTO/TiO2/(CsSnI3/CsSnGeI3/Cs3Bi2I9)/Cu2O/Au, resulted in a PCE of 27.59%, which needed extensive modification. To optimize the device structure, various parameters were rigorously tested, which included (i) tuning the individual thickness of each of the three absorber layers; (ii) studying the applicability of 4 different materials, i.e., TiO2, CdZnS, ZnO, and SnS2, for Electron Transfer Mediums (ETMs); and (iii) examining 5 compounds such as Spiro-OMeTAD, Cu2O, NiO, MoOx, and PEDOT:PSS;, for their usability as Hole Transfer Mediums (HTMs) as well. The finally optimized configuration FTO/TiO2/(CsSnI3/CsSnGeI3/Cs3Bi2I9)/MoOx/Au, where 0.8/0.1/0.1 μm of CsSnI3/CsSnGeI3/Cs3Bi2I9 is placed as a tri-layer, containing TiO2 as ETM of 0.1 μm and MoOx as HTM of 0.35 μm, which had been evaluated as the most-optimized material, exhibits notable photoelectric performance, i.e., JSC = 35.14 mA/cm2, VOC = 1.16 V, FF = 89.16%, and PCE = 36.34%. This cell underscores the remarkable potential of CsSnI3/CsSnGeI3/Cs3Bi2I9 as a perovskite tri-absorber layer along with its suitability for the various ETMs and HTMs that had been evaluated, directing in the path of manufacturing supremely efficient cells.
{"title":"Simulation and optimization of a CsSnI3/CsSnGeI3/Cs3Bi2I9 based triple absorber layer perovskite solar cell using SCAPS-1D","authors":"Umme Mabrura Umama , Mohammad Iftekher Ebne Jalal , Md. Adnan Faisal Siddique , Udhay Chowdhury , Md. Inzamam Ul Hoque , Md. Jahidur Rahman","doi":"10.1016/j.jpcs.2024.112480","DOIUrl":"10.1016/j.jpcs.2024.112480","url":null,"abstract":"<div><div>This paper demonstrates a numerical study on a novel triple absorber layer-based perovskite photovoltaic cell incorporating Cs<sub>3</sub>Bi<sub>2</sub>I<sub>9</sub>, which offers a relatively high bandgap (2.03 eV) along with superlative thermal stability. Combining it with CsSnGeI<sub>3</sub> & CsSnI<sub>3</sub> led to enhanced power conversion efficiency in the studied structures. The preliminary simulation performed for the cell configuration, FTO/TiO<sub>2</sub>/(CsSnI<sub>3</sub>/CsSnGeI<sub>3</sub>/Cs<sub>3</sub>Bi<sub>2</sub>I<sub>9</sub>)/Cu<sub>2</sub>O/Au, resulted in a PCE of 27.59%, which needed extensive modification. To optimize the device structure, various parameters were rigorously tested, which included (i) tuning the individual thickness of each of the three absorber layers; (ii) studying the applicability of 4 different materials, i.e., TiO<sub>2</sub>, CdZnS, ZnO, and SnS<sub>2</sub>, for Electron Transfer Mediums (ETMs); and (iii) examining 5 compounds such as Spiro-OMeTAD, Cu<sub>2</sub>O, NiO, MoO<sub>x</sub>, and PEDOT:PSS;, for their usability as Hole Transfer Mediums (HTMs) as well. The finally optimized configuration FTO/TiO<sub>2</sub>/(CsSnI<sub>3</sub>/CsSnGeI<sub>3</sub>/Cs<sub>3</sub>Bi<sub>2</sub>I<sub>9</sub>)/MoO<sub>x</sub>/Au, where 0.8/0.1/0.1 μm of CsSnI<sub>3</sub>/CsSnGeI<sub>3</sub>/Cs<sub>3</sub>Bi<sub>2</sub>I<sub>9</sub> is placed as a tri-layer, containing TiO<sub>2</sub> as ETM of 0.1 μm and MoO<sub>x</sub> as HTM of 0.35 μm, which had been evaluated as the most-optimized material, exhibits notable photoelectric performance, i.e., J<sub>SC</sub> = 35.14 mA/cm<sup>2</sup>, V<sub>OC</sub> = 1.16 V, FF = 89.16%, and PCE = 36.34%. This cell underscores the remarkable potential of CsSnI<sub>3</sub>/CsSnGeI<sub>3</sub>/Cs<sub>3</sub>Bi<sub>2</sub>I<sub>9</sub> as a perovskite tri-absorber layer along with its suitability for the various ETMs and HTMs that had been evaluated, directing in the path of manufacturing supremely efficient cells.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"198 ","pages":"Article 112480"},"PeriodicalIF":4.3,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-23DOI: 10.1016/j.jpcs.2024.112470
Maarten Vos , Pedro L. Grande
The implementation of dielectric functions based on the Random Phase Approximation (RPA), including those by Lindhard, Kaneko, and Levine-Louie, is presented systematically, incorporating the effects of electron relaxation (finite width) and lattice interactions. A straightforward approach is proposed to introduce electron relaxation time and binding effects without needing Mermin corrections or Kramers–Kronig (KK) relations. This method yields the same dielectric function as the Mermin-corrected Lindhard and Kaneko models in several limiting cases (optical, high momentum transfer, and static limits). Moreover, the result adheres to the Bethe and F sum rules and the real and imaginary part are Kramers–Kronig pairs. Still, it shows some variation at intermediate energy and momentum transfer. Additionally, the description of dispersion at high momentum transfer is refined to account for relativistic effects. A small library containing the implementation of these dielectric functions is provided as supplementary material.
{"title":"RPA Dielectric functions: Streamlined approach to relaxation effects, binding and high momentum dispersion","authors":"Maarten Vos , Pedro L. Grande","doi":"10.1016/j.jpcs.2024.112470","DOIUrl":"10.1016/j.jpcs.2024.112470","url":null,"abstract":"<div><div>The implementation of dielectric functions based on the Random Phase Approximation (RPA), including those by Lindhard, Kaneko, and Levine-Louie, is presented systematically, incorporating the effects of electron relaxation (finite width) and lattice interactions. A straightforward approach is proposed to introduce electron relaxation time and binding effects without needing Mermin corrections or Kramers–Kronig (KK) relations. This method yields the same dielectric function as the Mermin-corrected Lindhard and Kaneko models in several limiting cases (optical, high momentum transfer, and static limits). Moreover, the result adheres to the Bethe and F sum rules and the real and imaginary part are Kramers–Kronig pairs. Still, it shows some variation at intermediate energy and momentum transfer. Additionally, the description of dispersion at high momentum transfer is refined to account for relativistic effects. A small library containing the implementation of these dielectric functions is provided as supplementary material.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"198 ","pages":"Article 112470"},"PeriodicalIF":4.3,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142744581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-23DOI: 10.1016/j.jpcs.2024.112481
Yuan Liu , Wanping Liu , Xuelei Li , Jun Liu , Xiaoyan Liu , Aruuhan Bayaguud
Indium oxide (In2O3) anode material exhibits significant potential in lithium-ion batteries due to its low operating voltage and high theoretical specific capacity. However, its poor conductivity and substantial volume changes during Li+ insertion and extraction result in subpar rate performance and cycling stability. To address these issues, a binderless carbon-coated In2O3 anode is constructed, utilizing foam nickel as the current collector and liquid nitrile rubber (LNBR-820H) with high adhesion as the carbon source. This approach enhances conductivity and mitigates volume expansion problems. The synergistic effects of carbon coating and binderless construction yield the In2O3@C10%-Ni-BL anode with an initial discharge specific capacity of 1052.43 mAh g−1, a discharge specific capacity of 513.60 mAh g−1 after 200 cycles, and improved rate performance. These findings demonstrate the viability of this synergistic strategy, which not only circumvents the negative impact of binders on conductivity and enhances Li+ insertion/extraction efficiency but also increases the proportion of active materials, thereby improving both rate performance and cycling stability of the anode.
氧化铟(In2O3)负极材料因其低工作电压和高理论比容量而在锂离子电池中展现出巨大潜力。然而,由于其导电性较差,且在 Li+ 插入和提取过程中体积变化较大,导致其速率性能和循环稳定性不佳。为了解决这些问题,我们利用泡沫镍作为集流体,利用具有高附着力的液态丁腈橡胶(LNBR-820H)作为碳源,构建了一种无粘合剂碳涂层 In2O3 阳极。这种方法提高了导电性并缓解了体积膨胀问题。在碳涂层和无粘合剂结构的协同作用下,In2O3@C10%-Ni-BL 阳极的初始放电比容量为 1052.43 mAh g-1,200 次循环后的放电比容量为 513.60 mAh g-1,速率性能也有所提高。这些发现证明了这种协同策略的可行性,它不仅规避了粘合剂对电导率的负面影响,提高了 Li+ 插入/萃取效率,还增加了活性材料的比例,从而改善了阳极的速率性能和循环稳定性。
{"title":"Constructing a binderless carbon-coated In2O3 anode for high-performance lithium-ion batteries","authors":"Yuan Liu , Wanping Liu , Xuelei Li , Jun Liu , Xiaoyan Liu , Aruuhan Bayaguud","doi":"10.1016/j.jpcs.2024.112481","DOIUrl":"10.1016/j.jpcs.2024.112481","url":null,"abstract":"<div><div>Indium oxide (In<sub>2</sub>O<sub>3</sub>) anode material exhibits significant potential in lithium-ion batteries due to its low operating voltage and high theoretical specific capacity. However, its poor conductivity and substantial volume changes during Li<sup>+</sup> insertion and extraction result in subpar rate performance and cycling stability. To address these issues, a binderless carbon-coated In<sub>2</sub>O<sub>3</sub> anode is constructed, utilizing foam nickel as the current collector and liquid nitrile rubber (LNBR-820H) with high adhesion as the carbon source. This approach enhances conductivity and mitigates volume expansion problems. The synergistic effects of carbon coating and binderless construction yield the In<sub>2</sub>O<sub>3</sub>@C10%-Ni-BL anode with an initial discharge specific capacity of 1052.43 mAh g<sup>−1</sup>, a discharge specific capacity of 513.60 mAh g<sup>−1</sup> after 200 cycles, and improved rate performance. These findings demonstrate the viability of this synergistic strategy, which not only circumvents the negative impact of binders on conductivity and enhances Li<sup>+</sup> insertion/extraction efficiency but also increases the proportion of active materials, thereby improving both rate performance and cycling stability of the anode.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"198 ","pages":"Article 112481"},"PeriodicalIF":4.3,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-21DOI: 10.1016/j.jpcs.2024.112478
M.B. Tang, X.C. Liu, X.H. Pan
A new model of heat capacity is established for solid and liquid materials in the wide temperature range recently, and shows that heat capacity is also dependent on thermal expansion or volume. In this study, we further analyzed the physical meaning of the parameters in the model, and perfected the heat capacity model. The calculated heat capacity in the perfected model is well in accord with the experimental results. And a universal volume-energy relation in materials is predicted by the model, and has important theoretical value.
{"title":"General behavior of heat capacity and volume-energy relation in materials","authors":"M.B. Tang, X.C. Liu, X.H. Pan","doi":"10.1016/j.jpcs.2024.112478","DOIUrl":"10.1016/j.jpcs.2024.112478","url":null,"abstract":"<div><div>A new model of heat capacity is established for solid and liquid materials in the wide temperature range recently, and shows that heat capacity is also dependent on thermal expansion or volume. In this study, we further analyzed the physical meaning of the parameters in the model, and perfected the heat capacity model. The calculated heat capacity in the perfected model is well in accord with the experimental results. And a universal volume-energy relation in materials is predicted by the model, and has important theoretical value.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"198 ","pages":"Article 112478"},"PeriodicalIF":4.3,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-20DOI: 10.1016/j.jpcs.2024.112477
Adel El-marghany , Khair Muhammad , Muhammad Sajid , Mubashir Nazar , M. Kashif Masood , Nasarullah , Yazen M. Alawaideh , Javed Rehman
This study explores the structural, electronic, magnetic, optical, mechanical and thermoelectric (TE) properties of halide double perovskites (HDPs) A2NaMoCl6 (A = Cs, Rb) using density functional theory (DFT). The magnetic features of A2NaMoCl6 (A = Cs, Rb) showed that the total magnetic moments of 12.75181μB and 12.74960 μB, respectively. The stable nature of cubic A2NaMoCl6 (A = Cs, Rb) is supported by calculating the formation enthalpy (ΔH) and tolerance factor(τ). The negative ΔH values and τ values within stability range confirmed the stable nature of structure. Spin-polarized band structure (BS) and density of states (DOS) analysis show that Rb2NaMoCl6 and Cs2NaMoCl6 are direct bandgap semiconductors. Additionally, the optical properties including the absorption coefficient (α(ω)), real (ɛ1(ω)) and imaginary (ɛ2(ω)) components of the dielectric function ε(ω), optical conductivity (σ(ω)), refractive index (n(ω)), energy loss (L(ω)) and reflectivity (R(ω)) were also evaluated. Because of their large absorption and small reflectivity in the UV-VIS range, these HDPs possess considerable potential for applications in optoelectronic devices. In addition, we have also analyzed the thermoelectric properties which revealed that Cs2NaMoCl6 achieve higher efficiency with ZT value of over 0.8 at room temperature which signifies the importance of current study.
{"title":"Unraveling the complexities of A2NaMoCl6 (A=Cs, Rb) halide double perovskites through theoretical methods","authors":"Adel El-marghany , Khair Muhammad , Muhammad Sajid , Mubashir Nazar , M. Kashif Masood , Nasarullah , Yazen M. Alawaideh , Javed Rehman","doi":"10.1016/j.jpcs.2024.112477","DOIUrl":"10.1016/j.jpcs.2024.112477","url":null,"abstract":"<div><div>This study explores the structural, electronic, magnetic, optical, mechanical and thermoelectric (TE) properties of halide double perovskites (HDPs) A<sub>2</sub>NaMoCl<sub>6</sub> (A = Cs, Rb) using density functional theory (DFT). The magnetic features of A<sub>2</sub>NaMoCl<sub>6</sub> (A = Cs, Rb) showed that the total magnetic moments of 12.75181μ<sub>B</sub> and 12.74960 μ<sub>B</sub>, respectively. The stable nature of cubic A<sub>2</sub>NaMoCl<sub>6</sub> (A = Cs, Rb) is supported by calculating the formation enthalpy (ΔH) and tolerance factor(τ). The negative ΔH values and τ values within stability range confirmed the stable nature of structure. Spin-polarized band structure (BS) and density of states (DOS) analysis show that Rb<sub>2</sub>NaMoCl<sub>6</sub> and Cs<sub>2</sub>NaMoCl<sub>6</sub> are direct bandgap semiconductors. Additionally, the optical properties including the absorption coefficient (α(ω)), real (ɛ<sub>1</sub>(ω)) and imaginary (ɛ<sub>2</sub>(ω)) components of the dielectric function <em>ε</em>(ω), optical conductivity (σ(ω)), refractive index (n(ω)), energy loss (L(ω)) and reflectivity (R(ω)) were also evaluated. Because of their large absorption and small reflectivity in the UV-VIS range, these HDPs possess considerable potential for applications in optoelectronic devices. In addition, we have also analyzed the thermoelectric properties which revealed that Cs2NaMoCl6 achieve higher efficiency with ZT value of over 0.8 at room temperature which signifies the importance of current study.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"198 ","pages":"Article 112477"},"PeriodicalIF":4.3,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-19DOI: 10.1016/j.jpcs.2024.112475
Payal Bhattacharjee , Saswati Barman
We investigated and reported on a wide variety of gyrotropic modes in both isolated thick cylindrical magnetic vortices and lattices of such magnetic vortices arranged in square-lattice structures. In significantly thicker magnetic vortices, we see a higher-order flexure modes in addition to the uniform gyrotropic modes. We thoroughly examined the variation of the frequency and intensity of these modes with the thickness of the magnetic nanodots forming a vortex. We specifically looked at how the thickness, diameter, and aspect ratio of a single magnetic vortex and magnetic vortex lattice in various configurations affect the mode frequencies. When the magnetic vortex at the center is excited by an a.c. spin-polarized current with an excitation frequency equal to the collective gyrotropic frequencies of the lattice, we discuss the dynamics of the transfer of magnetic energy at three high symmetry points of the three-dimensional lattice of Permalloy nanodots with a vortex structure. The energy transmission in these lattice systems is estimated using the power and phase distributions for such configurations. Lattice configurations with substantially thicker nanodots consisting of uniform modes and higher-order flexure modes in the Eigen spectrum have transmission with uniform modes in specific directions and suppression in others, acting as a magnonic filter, and no transmission at all with higher-order modes. Such magnonic vortex lattice structures seek to improve the future prospects of technology and provide emerging applications in information processing devices, magnonic filters, three-dimensional waveguides, and magnonic crystals.
{"title":"Observation of higher-order gyrotropic modes and energy transfer in cylindrical ferromagnetic nanodots-based square lattices","authors":"Payal Bhattacharjee , Saswati Barman","doi":"10.1016/j.jpcs.2024.112475","DOIUrl":"10.1016/j.jpcs.2024.112475","url":null,"abstract":"<div><div>We investigated and reported on a wide variety of gyrotropic modes in both isolated thick cylindrical magnetic vortices and lattices of such magnetic vortices arranged in square-lattice structures. In significantly thicker magnetic vortices, we see a higher-order flexure modes in addition to the uniform gyrotropic modes. We thoroughly examined the variation of the frequency and intensity of these modes with the thickness of the magnetic nanodots forming a vortex. We specifically looked at how the thickness, diameter, and aspect ratio of a single magnetic vortex and magnetic vortex lattice in various configurations affect the mode frequencies. When the magnetic vortex at the center is excited by an a.c. spin-polarized current with an excitation frequency equal to the collective gyrotropic frequencies of the lattice, we discuss the dynamics of the transfer of magnetic energy at three high symmetry points of the three-dimensional lattice of Permalloy nanodots with a vortex structure. The energy transmission in these lattice systems is estimated using the power and phase distributions for such configurations. Lattice configurations with substantially thicker nanodots consisting of uniform modes and higher-order flexure modes in the Eigen spectrum have transmission with uniform modes in specific directions and suppression in others, acting as a magnonic filter, and no transmission at all with higher-order modes. Such magnonic vortex lattice structures seek to improve the future prospects of technology and provide emerging applications in information processing devices, magnonic filters, three-dimensional waveguides, and magnonic crystals.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"198 ","pages":"Article 112475"},"PeriodicalIF":4.3,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-19DOI: 10.1016/j.jpcs.2024.112474
N.A. Noor , M. Aslam Khan , Shanawer Niaz , Sohail Mumtaz , Sadia Nazir , Khalid M. Elhindi
Since spintronic devices can operate at far higher speeds, with less power consumption, and with unlimited durability, it is a developing subject that might eventually replace traditional electronics. Double perovskites have strong spin polarization ferromagnetism, which makes them ideal materials for spintronics. Density Functional Theory has been used in the current study to examine the structural, optoelectronic, magnetic, and thermoelectric characteristics of K2CuCrCl6 and K2CuCrBr6. PBE-sol is used to compute exchange correlation potential, and mBJ potential is used to measure bandgap accurately. The two materials demonstrate a cubic structure and thermodynamic stability, as demonstrated by their respective volume optimization and negative formation energy values. Materials that are ferromagnetic can be identified by their exchange constant values and spin-based energy-volume optimization. It has been noted that the primary contribution in net magnetic moment resulting from exchange splitting and the source for ferromagnetism is the 3-d states of Cr. Additionally, studies of band structure and density-of-states reveal that materials are semiconducting, having indirect bandgap values of 1.3 eV and 1.2 eV for K2CuCrCl6 and K2CuCrBr6, respectively, and substantial ultraviolet absorption in the optical spectra of the materials. In conclusion, the study of thermoelectric characteristics involves the assessment of thermal and electrical conductivities, Seebeck coefficient, power factor, and figure of merit (ZT). K2CuCrCl6 and K2CuCrBr6 both exhibit a high ZT, with values of 0.77 and 0.71, respectively. The findings of electronic and magnetic characteristics of K₂CuCrZ₆ (Z = Cl, Br) reveal that these investigated materials hold significant potential for applications in advanced technologies like spintronic and optoelectronic devices in which their stability and tunable magnetic behavior could be leveraged to develop versatile and more efficient components.
{"title":"Systematic study of spin dependent electronic, mechanical, optoelectronic and thermoelectric properties of halide double perovskites K2CuCrZ6 (Z = Cl, Br): DFT-calculations","authors":"N.A. Noor , M. Aslam Khan , Shanawer Niaz , Sohail Mumtaz , Sadia Nazir , Khalid M. Elhindi","doi":"10.1016/j.jpcs.2024.112474","DOIUrl":"10.1016/j.jpcs.2024.112474","url":null,"abstract":"<div><div>Since spintronic devices can operate at far higher speeds, with less power consumption, and with unlimited durability, it is a developing subject that might eventually replace traditional electronics. Double perovskites have strong spin polarization ferromagnetism, which makes them ideal materials for spintronics. Density Functional Theory has been used in the current study to examine the structural, optoelectronic, magnetic, and thermoelectric characteristics of K<sub>2</sub>CuCrCl<sub>6</sub> and K<sub>2</sub>CuCrBr<sub>6</sub>. PBE-sol is used to compute exchange correlation potential, and mBJ potential is used to measure bandgap accurately. The two materials demonstrate a cubic structure and thermodynamic stability, as demonstrated by their respective volume optimization and negative formation energy values. Materials that are ferromagnetic can be identified by their exchange constant values and spin-based energy-volume optimization. It has been noted that the primary contribution in net magnetic moment resulting from exchange splitting and the source for ferromagnetism is the 3-d states of Cr. Additionally, studies of band structure and density-of-states reveal that materials are semiconducting, having indirect bandgap values of 1.3 eV and 1.2 eV for K<sub>2</sub>CuCrCl<sub>6</sub> and K<sub>2</sub>CuCrBr<sub>6</sub>, respectively, and substantial ultraviolet absorption in the optical spectra of the materials. In conclusion, the study of thermoelectric characteristics involves the assessment of thermal and electrical conductivities, Seebeck coefficient, power factor, and figure of merit (ZT). K<sub>2</sub>CuCrCl<sub>6</sub> and K<sub>2</sub>CuCrBr<sub>6</sub> both exhibit a high ZT, with values of 0.77 and 0.71, respectively. The findings of electronic and magnetic characteristics of K₂CuCrZ₆ (Z = Cl, Br) reveal that these investigated materials hold significant potential for applications in advanced technologies like spintronic and optoelectronic devices in which their stability and tunable magnetic behavior could be leveraged to develop versatile and more efficient components.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"198 ","pages":"Article 112474"},"PeriodicalIF":4.3,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-19DOI: 10.1016/j.jpcs.2024.112476
Amit K. Bhojani , Hardik L. Kagdada , Dheeraj K. Singh
We constructed the van der Waals (vdW) heterostructures by stacking graphene (G) on top of carbon-based monochalcogenides (CX; X = S, Se, and Te) monolayer in two different patterns (I and II) and predicted various physical properties through first-principles calculations. Among the six heterostructures, three systems (CS/G in Pattern-I and II, and CSe/G in Pattern-II) were found to be most stable. Additionally, the calculated electronic properties confirmed that the CS/G and CSe/G heterostructures in Pattern II are indirect semiconductors with narrow band gap values of 0.49 and 0.30 eV, respectively. Notably, both heterostructures (CS/G and CSe/G) exhibit significantly larger electron carrier mobilities of 762.83 and 206.84 at room temperature, respectively. Furthermore, intrinsic and interface dipoles in both heterostructures were found to align along the +z axis, enhancing charge transfer at the interface and narrowing the band gap, particularly in CSe/G. This polarization effect contributes to the observed high electron mobility and thermoelectric performance. Electronic transport coefficients like the Seebeck coefficient, electrical conductivity, and thermoelectric power factor are predicted using the Boltzmann transport theory implemented in the BoltzTrap code. The highest power factor was achieved for the CSe/G heterostructure at , demonstrating its ability for good thermoelectric purposes. Besides, the computed optical properties revealed the potential of the CS/G heterostructure as a light absorber with an excellent solar light energy conversion efficiency of 23.57 % for solar cell device applications. Our predictions show that the novel 2D CX/G vdW heterostructures could be promising candidates for designing new solar and heat energy harvesting devices.
{"title":"Carbon monochalcogenides/graphene van der Waals heterostructures for sustainable energy harvesting","authors":"Amit K. Bhojani , Hardik L. Kagdada , Dheeraj K. Singh","doi":"10.1016/j.jpcs.2024.112476","DOIUrl":"10.1016/j.jpcs.2024.112476","url":null,"abstract":"<div><div>We constructed the van der Waals (vdW) heterostructures by stacking graphene (G) on top of carbon-based monochalcogenides (CX; X = S, Se, and Te) monolayer in two different patterns (I and II) and predicted various physical properties through first-principles calculations. Among the six heterostructures, three systems (CS/G in Pattern-I and II, and CSe/G in Pattern-II) were found to be most stable. Additionally, the calculated electronic properties confirmed that the CS/G and CSe/G heterostructures in Pattern II are indirect semiconductors with narrow band gap values of 0.49 and 0.30 eV, respectively. Notably, both heterostructures (CS/G and CSe/G) exhibit significantly larger electron carrier mobilities of 762.83 and 206.84 <span><math><mrow><msup><mi>m</mi><mn>2</mn></msup><mo>/</mo><mi>V</mi><mi>s</mi></mrow></math></span> at room temperature, respectively. Furthermore, intrinsic and interface dipoles in both heterostructures were found to align along the +z axis, enhancing charge transfer at the interface and narrowing the band gap, particularly in CSe/G. This polarization effect contributes to the observed high electron mobility and thermoelectric performance. Electronic transport coefficients like the Seebeck coefficient, electrical conductivity, and thermoelectric power factor are predicted using the Boltzmann transport theory implemented in the BoltzTrap code. The highest power factor <span><math><mrow><mn>249</mn></mrow></math></span> <span><math><mrow><mi>m</mi><mi>W</mi><mo>/</mo><mi>m</mi><msup><mi>K</mi><mn>2</mn></msup></mrow></math></span> was achieved for the CSe/G heterostructure at <span><math><mrow><mn>300</mn><mspace></mspace><mi>K</mi></mrow></math></span>, demonstrating its ability for good thermoelectric purposes. Besides, the computed optical properties revealed the potential of the CS/G heterostructure as a light absorber with an excellent solar light energy conversion efficiency <span><math><mrow><mo>(</mo><mi>η</mi><mo>)</mo></mrow></math></span> of 23.57 % for solar cell device applications. Our predictions show that the novel 2D CX/G vdW heterostructures could be promising candidates for designing new solar and heat energy harvesting devices.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"198 ","pages":"Article 112476"},"PeriodicalIF":4.3,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Biomass-derived porous carbon materials, enriched with heteroatom doping, particularly nitrogen and oxygen, have garnered significant attention as promising candidates for supercapacitor electrodes. By utilizing litchi peel, a byproduct of the widely cultivated fruit, as a precursor, we successfully synthesized a series of N/O co-doped porous carbon materials (NO-LPC-y). Notably, NO-LPC-1 exhibits a remarkable specific surface area of 996.05 m2 g−1 and a substantial microporosity percentage of 50.94 %. The high content of nitrogen (6.3 %) and oxygen (18.01 %) synergistically enhances the wettability and capacitance properties of the material. In a 6 M KOH three-electrode system, NO-LPC-1 demonstrated a specific capacitance of 320.0 F g−1, accompanied by an impressive capacitance retention of 74.66 %. Furthermore, symmetric supercapacitors constructed with NO-LPC-1 achieved notable energy densities ranging from 8.63 (250 Wh·kg−1/6 M KOH) to 15.36 Wh·kg−1 (400.1 W kg−1/1 M Na2SO4) in various electrolytes while displaying remarkable cycling stability, retaining 96.9 % of their initial capacitance after 12,000 charge/discharge cycles. This study validates the efficacy of our method in enhancing the electrochemical properties of biomass-derived porous carbon electrodes, thereby advancing the development of high-performance supercapacitors.
作为超级电容器电极的理想候选材料,富含杂原子(尤其是氮和氧)的生物质多孔碳材料已引起广泛关注。我们利用荔枝皮(一种广泛栽培水果的副产品)作为前体,成功合成了一系列氮/氧共掺多孔碳材料(NO-LPC-y)。值得注意的是,NO-LPC-1 的比表面积高达 996.05 m2 g-1,微孔率高达 50.94 %。高含量的氮(6.3%)和氧(18.01%)协同增强了材料的润湿性和电容特性。在 6 M KOH 三电极系统中,NO-LPC-1 的比电容为 320.0 F g-1,电容保持率高达 74.66%。此外,用 NO-LPC-1 构建的对称超级电容器在各种电解质中实现了从 8.63(250 Wh-kg-1/6 M KOH)到 15.36 Wh-kg-1(400.1 W kg-1/1 M Na2SO4)不等的显著能量密度,同时显示出显著的循环稳定性,在 12,000 次充电/放电循环后仍能保持 96.9% 的初始电容。这项研究验证了我们的方法在提高生物质多孔碳电极电化学性能方面的功效,从而推动了高性能超级电容器的开发。
{"title":"N/O co-doped litchi peel derived porous carbon materials for supercapacitors","authors":"Yuanyuan Wang, Xingshen Dong, Yingjing Xia, Wenyi Wang, Xueqin Wang, Yanxiu Liu, Peng Qiao, Geng Zhang, Shetian Liu","doi":"10.1016/j.jpcs.2024.112472","DOIUrl":"10.1016/j.jpcs.2024.112472","url":null,"abstract":"<div><div>Biomass-derived porous carbon materials, enriched with heteroatom doping, particularly nitrogen and oxygen, have garnered significant attention as promising candidates for supercapacitor electrodes. By utilizing litchi peel, a byproduct of the widely cultivated fruit, as a precursor, we successfully synthesized a series of N/O co-doped porous carbon materials (NO-LPC-<em>y</em>). Notably, NO-LPC-1 exhibits a remarkable specific surface area of 996.05 m<sup>2</sup> g<sup>−1</sup> and a substantial microporosity percentage of 50.94 %. The high content of nitrogen (6.3 %) and oxygen (18.01 %) synergistically enhances the wettability and capacitance properties of the material. In a 6 M KOH three-electrode system, NO-LPC-1 demonstrated a specific capacitance of 320.0 F g<sup>−1</sup>, accompanied by an impressive capacitance retention of 74.66 %. Furthermore, symmetric supercapacitors constructed with NO-LPC-1 achieved notable energy densities ranging from 8.63 (250 Wh·kg<sup>−1</sup>/6 M KOH) to 15.36 Wh·kg<sup>−1</sup> (400.1 W kg<sup>−1</sup>/1 M Na<sub>2</sub>SO<sub>4</sub>) in various electrolytes while displaying remarkable cycling stability, retaining 96.9 % of their initial capacitance after 12,000 charge/discharge cycles. This study validates the efficacy of our method in enhancing the electrochemical properties of biomass-derived porous carbon electrodes, thereby advancing the development of high-performance supercapacitors.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"198 ","pages":"Article 112472"},"PeriodicalIF":4.3,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142703526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}