Pub Date : 2025-03-20DOI: 10.1016/j.solidstatesciences.2025.107911
Cansu Karakaya, Ediz Ercenk, Şenol Yilmaz
This study produced glass materials by adding La2O3 to Blast Furnace Slag in specific proportions. Partial crystallization was attempted to be achieved by a composition effect. A partial crystallization effect is provided by composition and Spinodal phase separation. X-ray diffraction analysis (XRD), Raman analysis, and differential thermal analysis (DTA) tests were performed on the produced samples. An optical microscope was used to observe phase separation. Mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), mean free path (MFP), values of half-value layers (HVL), and tenth-value layers (TVL) measurements were made experimentally for radiation shielding properties. Experimental values were checked with theoretical calculations, and experimental/theoretical results were very close. LAC values were determined in the range of 0.1537–0.2607 cm−1 depending on energy and composition. While the values decreased with photon energy, they increased with La2O3 addition. HVL values were measured as 2.6588–4.5109 cm depending on the energy and composition, these values increased with energy and decreased with La2O3 addition. Phase separation controlled partial crystallization effect was achieved by specific La2O3 addition. It was observed that the La2O3 effect improved shielding properties, and partial crystallization provided positive effects, especially in LAC values.
{"title":"Effect of self partial crystallization with heavy cation addition on radiation shielding properties","authors":"Cansu Karakaya, Ediz Ercenk, Şenol Yilmaz","doi":"10.1016/j.solidstatesciences.2025.107911","DOIUrl":"10.1016/j.solidstatesciences.2025.107911","url":null,"abstract":"<div><div>This study produced glass materials by adding La<sub>2</sub>O<sub>3</sub> to Blast Furnace Slag in specific proportions. Partial crystallization was attempted to be achieved by a composition effect. A partial crystallization effect is provided by composition and Spinodal phase separation. X-ray diffraction analysis (XRD), Raman analysis, and differential thermal analysis (DTA) tests were performed on the produced samples. An optical microscope was used to observe phase separation. Mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), mean free path (MFP), values of half-value layers (HVL), and tenth-value layers (TVL) measurements were made experimentally for radiation shielding properties. Experimental values were checked with theoretical calculations, and experimental/theoretical results were very close. LAC values were determined in the range of 0.1537–0.2607 cm<sup>−1</sup> depending on energy and composition. While the values decreased with photon energy, they increased with La<sub>2</sub>O<sub>3</sub> addition. HVL values were measured as 2.6588–4.5109 cm depending on the energy and composition, these values increased with energy and decreased with La<sub>2</sub>O<sub>3</sub> addition. Phase separation controlled partial crystallization effect was achieved by specific La<sub>2</sub>O<sub>3</sub> addition. It was observed that the La<sub>2</sub>O<sub>3</sub> effect improved shielding properties, and partial crystallization provided positive effects, especially in LAC values.</div></div>","PeriodicalId":432,"journal":{"name":"Solid State Sciences","volume":"163 ","pages":"Article 107911"},"PeriodicalIF":3.4,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143716184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
β-Rhombohedral boron (β-boron) represents one of the most popular and important allotropic forms of elemental boron. The unit cell of β-boron crystal consists of B106.6 with a complicated and relatively open structure. We have previously reported the abrupt lattice expansion and shrinkage of β-boron crystal by thermal treatment above 700 K and photoirradiation at room temperature. Our recent studies, combined with X-ray diffraction and atom probe tomography experiments, suggest that the lattice expansion and shrinkage are related to the absorption and release of hydrogen into the structure. The results lead us to a new application of β-boron as a photo-switchable hydrogen storage material.
{"title":"Lattice expansion due to hydrogen absorption into β-rhombohedral boron","authors":"Takanobu Hiroto , Hossein Sepehri-Amin , Naoki Uemura , Naoya Miyauchi , Wataru Hayami , Tadakatsu Ohkubo , Tadashi Ogitsu , Kohei Soga , Kaoru Kimura","doi":"10.1016/j.solidstatesciences.2025.107907","DOIUrl":"10.1016/j.solidstatesciences.2025.107907","url":null,"abstract":"<div><div>β-Rhombohedral boron (<em>β</em>-boron) represents one of the most popular and important allotropic forms of elemental boron. The unit cell of β-boron crystal consists of B<sub>106.6</sub> with a complicated and relatively open structure. We have previously reported the abrupt lattice expansion and shrinkage of <em>β</em>-boron crystal by thermal treatment above 700 K and photoirradiation at room temperature. Our recent studies, combined with X-ray diffraction and atom probe tomography experiments, suggest that the lattice expansion and shrinkage are related to the absorption and release of hydrogen into the structure. The results lead us to a new application of <em>β</em>-boron as a photo-switchable hydrogen storage material.</div></div>","PeriodicalId":432,"journal":{"name":"Solid State Sciences","volume":"163 ","pages":"Article 107907"},"PeriodicalIF":3.4,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-18DOI: 10.1016/j.solidstatesciences.2025.107910
Omair Shahid, Jai Prakash
The present work describes the syntheses of three new chalcogenides, Ag2Sc2Sn2S8, Cu1.9(1)Sc1.9(1)Sn2.1(1)S8, and Cu1.4(1)Sc1.4(1)Sn2.6(1)Se8 with disordered spinel structures (space group: Fdm) as established from single crystal X-ray diffraction studies. As expected, the unit cell volume of the cubic Ag2Sc2Sn2S8 (a = 10.722(4) Å) structure is bigger than that of the Cu-containing sulfide Cu1.9(1)Sc1.9(1)Sn2.1(1)S8 (a = 10.4431(3) Å). Similarly, the refined a-lattice constant of 10.8961(10) Å for the Cu1.4(1)Sc1.4(1)Sn2.6(1)Se8 structure is longer than the sulfide Cu1.9(1)Sc1.9(1)Sn2.1(1)S8. These structures are based on cubic close packing of chalcogen atoms (S/Se) where the Sc and Sn atoms co-occupy the same octahedral sites, unlike the Cu/Ag atoms, which are distributed over the tetrahedral sites in the title structures. A phase pure polycrystalline selenide with the loaded composition of Cu1.4Sc1.4Sn2.6Se8 was prepared by a high-temperature reaction of elements at 1223 K. The polycrystalline samples with the loaded compositions of Cu1.9Sc1.9Sn2.1S8 and Ag2Sc2Sn2S8 were biphasic, consisting of the target spinel and SnS phases. The resistivity, Seebeck coefficient, and optical absorption studies show that the polycrystalline Cu1.4Sc1.4Sn2.6Se8 is an n-type semiconductor with a direct bandgap of 1.0(1) eV. The magnitude of the Seebeck coefficient value of the Se-sample varies from 122 μV/K (at 773 K) to 185 μV/K (at 573 K). The Se-sample shows a relatively high thermal conductivity (κtot) value of 1.75 Wm−1K−1 near room temperature, which drops to a low value of 0.77 Wm−1K−1 at 773 K. The biphasic samples, Cu1.9Sc1.9Sn2.1S8 and Ag2Sc2Sn2S8, also show semiconducting behavior from the resistivity and optical absorption studies.
{"title":"Syntheses, crystal structures, and physical properties of three new chalcospinels: Ag2Sc2Sn2S8, Cu1.9(1)Sc1.9(1)Sn2.1(1)S8, and Cu1.4(1)Sc1.4(1)Sn2.6(1)Se8","authors":"Omair Shahid, Jai Prakash","doi":"10.1016/j.solidstatesciences.2025.107910","DOIUrl":"10.1016/j.solidstatesciences.2025.107910","url":null,"abstract":"<div><div>The present work describes the syntheses of three new chalcogenides, Ag<sub>2</sub>Sc<sub>2</sub>Sn<sub>2</sub>S<sub>8</sub>, Cu<sub>1.9(1)</sub>Sc<sub>1.9(1)</sub>Sn<sub>2.1(1)</sub>S<sub>8</sub>, and Cu<sub>1.4(1)</sub>Sc<sub>1.4(1)</sub>Sn<sub>2.6(1)</sub>Se<sub>8</sub> with disordered spinel structures (space group: <em>Fd</em><span><math><mrow><mover><mn>3</mn><mo>‾</mo></mover></mrow></math></span><em>m</em>) as established from single crystal X-ray diffraction studies. As expected, the unit cell volume of the cubic Ag<sub>2</sub>Sc<sub>2</sub>Sn<sub>2</sub>S<sub>8</sub> (<em>a</em> = 10.722(4) Å) structure is bigger than that of the Cu-containing sulfide Cu<sub>1.9(1)</sub>Sc<sub>1.9(1)</sub>Sn<sub>2.1(1)</sub>S<sub>8</sub> (<em>a</em> = 10.4431(3) Å). Similarly, the refined <em>a</em>-lattice constant of 10.8961(10) Å for the Cu<sub>1.4(1)</sub>Sc<sub>1.4(1)</sub>Sn<sub>2.6(1)</sub>Se<sub>8</sub> structure is longer than the sulfide Cu<sub>1.9(1)</sub>Sc<sub>1.9(1)</sub>Sn<sub>2.1(1)</sub>S<sub>8</sub>. These structures are based on cubic close packing of chalcogen atoms (S/Se) where the Sc and Sn atoms co-occupy the same octahedral sites, unlike the Cu/Ag atoms, which are distributed over the tetrahedral sites in the title structures. A phase pure polycrystalline selenide with the loaded composition of Cu<sub>1.4</sub>Sc<sub>1.4</sub>Sn<sub>2.6</sub>Se<sub>8</sub> was prepared by a high-temperature reaction of elements at 1223 K. The polycrystalline samples with the loaded compositions of Cu<sub>1.9</sub>Sc<sub>1.9</sub>Sn<sub>2.1</sub>S<sub>8</sub> and Ag<sub>2</sub>Sc<sub>2</sub>Sn<sub>2</sub>S<sub>8</sub> were biphasic, consisting of the target spinel and SnS phases. The resistivity, Seebeck coefficient, and optical absorption studies show that the polycrystalline Cu<sub>1.4</sub>Sc<sub>1.4</sub>Sn<sub>2.6</sub>Se<sub>8</sub> is an <em>n</em>-type semiconductor with a direct bandgap of 1.0(1) eV. The magnitude of the Seebeck coefficient value of the Se-sample varies from 122 μV/K (at 773 K) to 185 μV/K (at 573 K). The Se-sample shows a relatively high thermal conductivity (<em>κ</em><sub><em>tot</em></sub>) value of 1.75 Wm<sup>−1</sup>K<sup>−1</sup> near room temperature, which drops to a low value of 0.77 Wm<sup>−1</sup>K<sup>−1</sup> at 773 K. The biphasic samples, Cu<sub>1.9</sub>Sc<sub>1.9</sub>Sn<sub>2.1</sub>S<sub>8</sub> and Ag<sub>2</sub>Sc<sub>2</sub>Sn<sub>2</sub>S<sub>8</sub>, also show semiconducting behavior from the resistivity and optical absorption studies.</div></div>","PeriodicalId":432,"journal":{"name":"Solid State Sciences","volume":"163 ","pages":"Article 107910"},"PeriodicalIF":3.4,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-17DOI: 10.1016/j.solidstatesciences.2025.107906
Yana Yu Zhuravleva , Andrei I. Klyndyuk , Ekaterina A. Tugova , Nikolai N. Gundilovich , Maria V. Tomkovich
Using ceramic method, the continuous serie of NdBa1–xSrxFe2/3Co2/3Cu2/3O6–δ (0.0 ≤ x ≤ 1.0) (NBS) solid solutions was prepared, their crystal structure, microstructure, oxygen nonstoichiometry, thermal expansion, electrical conductivity, and Seebeck coefficient were studied. It was found, that NBS compounds possessed perovskite-like structure and were p-type semiconductors, which lattice constants, oxygen nonstoichiometry index (δ), and Seebeck coefficient decreased, but electrical conductivity increased at substitution of barium by strontium. Near x ≈ 0.5 the phase transition from tetragonal phase into cubic one took place. The complex oxides with composition near this point (x = 0.4, 0.6) were possessed the lowest sinterability, had maximal microstrains, and minimal microhardness and values of grain sizes among the samples studied. Thermal and chemical expansion coefficients of NBS samples varied within (15.3–17.2)·10−6 K−1 and (0.94–17.0)·10−3 respectively, and, all in all, increased by x rising. The largest value of electrical conductivity (σ800 ≈ 290 S·cm−1) was fixed for the NdBa0.2Sr0.8Fe2/3Co2/3Cu2/3O6–δ solid solution.
{"title":"Structural, thermal and electrical properties of the ceramics in the NdBaFe2/3Co2/3Cu2/3O6–δ–NdSrFe2/3Co2/3Cu2/3O6–δ system","authors":"Yana Yu Zhuravleva , Andrei I. Klyndyuk , Ekaterina A. Tugova , Nikolai N. Gundilovich , Maria V. Tomkovich","doi":"10.1016/j.solidstatesciences.2025.107906","DOIUrl":"10.1016/j.solidstatesciences.2025.107906","url":null,"abstract":"<div><div>Using ceramic method, the continuous serie of NdBa<sub>1–<em>x</em></sub>Sr<sub><em>x</em></sub>Fe<sub>2/3</sub>Co<sub>2/3</sub>Cu<sub>2/3</sub>O<sub>6–δ</sub> (0.0 ≤ <em>x</em> ≤ 1.0) (NBS) solid solutions was prepared, their crystal structure, microstructure, oxygen nonstoichiometry, thermal expansion, electrical conductivity, and Seebeck coefficient were studied. It was found, that NBS compounds possessed perovskite-like structure and were <em>p</em>-type semiconductors, which lattice constants, oxygen nonstoichiometry index (δ), and Seebeck coefficient decreased, but electrical conductivity increased at substitution of barium by strontium. Near <em>x</em> ≈ 0.5 the phase transition from tetragonal phase into cubic one took place. The complex oxides with composition near this point (<em>x</em> = 0.4, 0.6) were possessed the lowest sinterability, had maximal microstrains, and minimal microhardness and values of grain sizes among the samples studied. Thermal and chemical expansion coefficients of NBS samples varied within (15.3–17.2)·10<sup>−6</sup> K<sup>−1</sup> and (0.94–17.0)·10<sup>−3</sup> respectively, and, all in all, increased by <em>x</em> rising. The largest value of electrical conductivity (σ<sub>800</sub> ≈ 290 S·cm<sup>−1</sup>) was fixed for the NdBa<sub>0.2</sub>Sr<sub>0.8</sub>Fe<sub>2/3</sub>Co<sub>2/3</sub>Cu<sub>2/3</sub>O<sub>6–δ</sub> solid solution.</div></div>","PeriodicalId":432,"journal":{"name":"Solid State Sciences","volume":"163 ","pages":"Article 107906"},"PeriodicalIF":3.4,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this research, the carbon substrate of graphitic carbon nitride was synthesized by polymerization route, and at the same time phosphorus element was successfully doped in its structure. Then CuBi2O4 nanoparticles were coupled and decorated on the layers of g-C3N4. Morphology, structural properties, and photocatalytic activity of the new heterogeneous nanocomposites (P-doped g-C3N4/CuBi2O4) were identified and evaluated using different and suitable spectroscopic and imaging methods. The synthesized nanocomposites were used as photocatalysts in the reduction of nitroaromatic compounds, which had high photocatalytic activity so that the conversion of nitrobenzene to aminobenzene (aniline) had a 100 % yield within 60 min. In the above reactions, hydrazine monohydrate was used as a hydrogen supplier. P-doped g-C3N4/CuBi2O4 photocatalyst had high recyclability and reusability. So after seven reuses, no measurable change was observed in the amount of nanocomposite and the rate of reaction efficiency.
{"title":"Synthesis and characterization of P-doped g-C3N4/CuBi2O4 as a new heterogeneous nanocomposite for photocatalytic reduction of nitroaromatic compounds","authors":"Elham Hosseinian, Ali Oji Moghanlou, Farshid Salimi Nanekaran, Behnam Khanizadeh, Nayer Mohammadian Tarighi","doi":"10.1016/j.solidstatesciences.2025.107897","DOIUrl":"10.1016/j.solidstatesciences.2025.107897","url":null,"abstract":"<div><div>In this research, the carbon substrate of graphitic carbon nitride was synthesized by polymerization route, and at the same time phosphorus element was successfully doped in its structure. Then CuBi<sub>2</sub>O<sub>4</sub> nanoparticles were coupled and decorated on the layers of g-C<sub>3</sub>N<sub>4</sub>. Morphology, structural properties, and photocatalytic activity of the new heterogeneous nanocomposites (P-doped g-C<sub>3</sub>N<sub>4</sub>/CuBi<sub>2</sub>O<sub>4</sub>) were identified and evaluated using different and suitable spectroscopic and imaging methods. The synthesized nanocomposites were used as photocatalysts in the reduction of nitroaromatic compounds, which had high photocatalytic activity so that the conversion of nitrobenzene to aminobenzene (aniline) had a 100 % yield within 60 min. In the above reactions, hydrazine monohydrate was used as a hydrogen supplier. P-doped g-C<sub>3</sub>N<sub>4</sub>/CuBi<sub>2</sub>O<sub>4</sub> photocatalyst had high recyclability and reusability. So after seven reuses, no measurable change was observed in the amount of nanocomposite and the rate of reaction efficiency.</div></div>","PeriodicalId":432,"journal":{"name":"Solid State Sciences","volume":"163 ","pages":"Article 107897"},"PeriodicalIF":3.4,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-14DOI: 10.1016/j.solidstatesciences.2025.107903
S. Ashoka , H.M. Akshaya , M. Shirisha , N.S. Venkataramanan , K. Yogesh , Narayana Sanaga , R.T. Yogeeshwari
Potential electrocatalytic system based on monoclinic Co2V2O7 nanorods (Co2V2O7 NRs) is proposed to realize formaldehyde (H2CO) assisted green hydrogen production at ultra-low overpotential in an alkaline electrolyte. The mechanistic knowledge of H2CO assisted hydrogen production over Co2V2O7 NR surface is gained by the combination of experimental and density functional theory. The computational studies confirm that the Co2V2O7 surface exhibit highest adsorption energy of −0.185 eV towards H2CO oxidation compared to V2O5 (−0.144 eV) and Co3O4 (−0.108 eV). The Co2V2O7 NRs renders kinetically more favorable surface for selective oxidation of H2CO (SOF) compared to its counterparts Co3O4 and V2O5. The SOF over Co2V2O7 NR surface results in green hydrogen at ultra-low overpotential and high-valued low-cost chemical formic acid. The Co2V2O7 NRs exhibit an ultra-low onset potential of 1.26 V vs RHE towards FOR in three electrode configuration while Co2V2O7 NRs || Co2V2O7 cell needs a low cell potential of only 1.48 V at 10 mA cm−2 in H2CO assisted hydrogen production. The proposed research opens a new way to treat H2CO contaminated water with simultaneous production of green hydrogen.
{"title":"Insights on the electrooxidation of formaldehyde over bimetallic Co2V2O7 nanorod and its implication towards water electrolysis","authors":"S. Ashoka , H.M. Akshaya , M. Shirisha , N.S. Venkataramanan , K. Yogesh , Narayana Sanaga , R.T. Yogeeshwari","doi":"10.1016/j.solidstatesciences.2025.107903","DOIUrl":"10.1016/j.solidstatesciences.2025.107903","url":null,"abstract":"<div><div>Potential electrocatalytic system based on monoclinic Co<sub>2</sub>V<sub>2</sub>O<sub>7</sub> nanorods (Co<sub>2</sub>V<sub>2</sub>O<sub>7</sub> NRs) is proposed to realize formaldehyde (H<sub>2</sub>CO) assisted green hydrogen production at ultra-low overpotential in an alkaline electrolyte. The mechanistic knowledge of H<sub>2</sub>CO assisted hydrogen production over Co<sub>2</sub>V<sub>2</sub>O<sub>7</sub> NR surface is gained by the combination of experimental and density functional theory. The computational studies confirm that the Co<sub>2</sub>V<sub>2</sub>O<sub>7</sub> surface exhibit highest adsorption energy of −0.185 eV towards H<sub>2</sub>CO oxidation compared to V<sub>2</sub>O<sub>5</sub> (−0.144 eV) and Co<sub>3</sub>O<sub>4</sub> (−0.108 eV). The Co<sub>2</sub>V<sub>2</sub>O<sub>7</sub> NRs renders kinetically more favorable surface for selective oxidation of H<sub>2</sub>CO (SOF) compared to its counterparts Co<sub>3</sub>O<sub>4</sub> and V<sub>2</sub>O<sub>5</sub>. The SOF over Co<sub>2</sub>V<sub>2</sub>O<sub>7</sub> NR surface results in green hydrogen at ultra-low overpotential and high-valued low-cost chemical formic acid. The Co<sub>2</sub>V<sub>2</sub>O<sub>7</sub> NRs exhibit an ultra-low onset potential of 1.26 V vs RHE towards FOR in three electrode configuration while Co<sub>2</sub>V<sub>2</sub>O<sub>7</sub> NRs || Co<sub>2</sub>V<sub>2</sub>O<sub>7</sub> cell needs a low cell potential of only 1.48 V at 10 mA cm<sup>−2</sup> in H<sub>2</sub>CO assisted hydrogen production. The proposed research opens a new way to treat H<sub>2</sub>CO contaminated water with simultaneous production of green hydrogen.</div></div>","PeriodicalId":432,"journal":{"name":"Solid State Sciences","volume":"163 ","pages":"Article 107903"},"PeriodicalIF":3.4,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-13DOI: 10.1016/j.solidstatesciences.2025.107904
Lin Cheng , Hongxia Liu , Lu Gao , Lijun Zhai , Junsong He , Zhongyuan Yang , Minghao Lv , Yan Zhang , Zhigang Sun
GeTe thermoelectrics have received widespread attention due to their excellent thermoelectric performance. In this paper, GeTe samples are prepared by a melt spinning process combined with hot-pressing. The samples have a lower carrier concentration compared to those prepared by the traditional melting method, and the enhanced grain boundary scattering leads to a reduction in thermal conductivity. Zn doping is found to increase the density of states effective mass, leading to an enhanced Seebeck coefficient while maintaining a high mobility. The intensified phonon scattering of point defects and stacking faults in Ge1-xZnxTe samples leads to significantly reduced lattice thermal conductivity, with a minimum value of only ∼0.51 Wm−1K−1 at 775 K. The Ge0.98Zn0.02Te sample achieves a maximum zT∼1.4 at 775 K. The further introduced Sc not only enhances the phonon scattering from multi-scale microstructures to reduce the lattice thermal conductivity, resulting in the lowest value of ∼0.29 Wm−1K−1, but also improves the Vickers hardness, which is about 43 % higher than the Zn doped samples. This work demonstrates the Zn and Sc co-doped GeTe samples as excellent thermoelectric materials for practical applications.
{"title":"Thermoelectric properties of Zn/Sc codoped GeTe prepared by melt-spinning method","authors":"Lin Cheng , Hongxia Liu , Lu Gao , Lijun Zhai , Junsong He , Zhongyuan Yang , Minghao Lv , Yan Zhang , Zhigang Sun","doi":"10.1016/j.solidstatesciences.2025.107904","DOIUrl":"10.1016/j.solidstatesciences.2025.107904","url":null,"abstract":"<div><div>GeTe thermoelectrics have received widespread attention due to their excellent thermoelectric performance. In this paper, GeTe samples are prepared by a melt spinning process combined with hot-pressing. The samples have a lower carrier concentration compared to those prepared by the traditional melting method, and the enhanced grain boundary scattering leads to a reduction in thermal conductivity. Zn doping is found to increase the density of states effective mass, leading to an enhanced Seebeck coefficient while maintaining a high mobility. The intensified phonon scattering of point defects and stacking faults in Ge<sub>1-<em>x</em></sub>Zn<sub><em>x</em></sub>Te samples leads to significantly reduced lattice thermal conductivity, with a minimum value of only ∼0.51 Wm<sup>−1</sup>K<sup>−1</sup> at 775 K. The Ge<sub>0.98</sub>Zn<sub>0.02</sub>Te sample achieves a maximum <em>zT</em>∼1.4 at 775 K. The further introduced Sc not only enhances the phonon scattering from multi-scale microstructures to reduce the lattice thermal conductivity, resulting in the lowest value of ∼0.29 Wm<sup>−1</sup>K<sup>−1</sup>, but also improves the Vickers hardness, which is about 43 % higher than the Zn doped samples. This work demonstrates the Zn and Sc co-doped GeTe samples as excellent thermoelectric materials for practical applications.</div></div>","PeriodicalId":432,"journal":{"name":"Solid State Sciences","volume":"163 ","pages":"Article 107904"},"PeriodicalIF":3.4,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-13DOI: 10.1016/j.solidstatesciences.2025.107905
Nidhi Manhas , Lalita S. Kumar , Pankaj Kumar , Vandna Sharma , Rajeev S. Joshi , Rangappa Keri , A.K. Swetha , Vinayak Adimule
In the present work, self-organized non-polar liquid crystalline (LC) molecules (3b, 3c) were anchored by multi-walled carbon nanotubes (MWCNTs) to enhance optical and electrical properties. The 3b, 3c@MWCNTs LC-intercalated systems (IS) exhibited co-axial distribution of MWCNTs with orderly arrangement showing well-aligned interference colors with banded patterns in the textures, as observed using a polarizing optical microscope. Steady state photoluminescence studies unveiled sharp emission peaks around blue, yellow and red bands, and a broad emission peaks around violet band for 3b, 3c@MWCNTs LC-IS. Further, the Stoke's shifts were observed larger indicating that LC-IS can be used for display applications with high contrast ratio. Fluorescence decay studies demonstrated that average lifetime (τ) was in the range of 0.200ns–0.089ns and 0.087–0.139ns for 3b@MWCNTs and 3c@MWCNTs LC-IS, respectively and were lower than pure 3b, 3c LCs. Due to which it influenced the faster recombination of the excited photons, enabling effective charge transfer rates, and aid in the attainment of quantum equilibrium states quickly in the LC matrix. Furthermore, capacitance-voltage measurements of 3b@MWCNTs LC-IS showed quasi-static complete alignment at 42 °C and 3.2V, however, stable at 10V with relative dielectric permittivity of 0.023. The polarization studies confirmed asymmetric nature of 3b@MWCNTs LC-IS, showing saturation value of 41.8 μC/cm2 with remnant polarization of 21.4 μC/cm2. PFUND studies evidenced that polarization of 3b@MWCNTs LC-IS followed the rate of pulse and the delay at 40 °C and 42 °C with 2V of bias voltage. In contrast, 3c@MWCNTs LC-IS mild reorientation was seen at 2.4V and 7V with breakdown at 10V and polarization didn't follow rate of pulse and delay at any applied voltages. From the reported research work a new pathway has been opened for further exploration of electro-optical properties of various LC molecules, and can serve as a reference to improve electrical and optical properties of LC-IS systems for advanced display applications.
{"title":"Anchoring of liquid crystal molecules on multi-walled carbon nanotubes and their effects on enhanced photoluminescence dynamics, fluorescence decay and distinctive electrical properties","authors":"Nidhi Manhas , Lalita S. Kumar , Pankaj Kumar , Vandna Sharma , Rajeev S. Joshi , Rangappa Keri , A.K. Swetha , Vinayak Adimule","doi":"10.1016/j.solidstatesciences.2025.107905","DOIUrl":"10.1016/j.solidstatesciences.2025.107905","url":null,"abstract":"<div><div>In the present work, self-organized non-polar liquid crystalline (LC) molecules (3b, 3c) were anchored by multi-walled carbon nanotubes (MWCNTs) to enhance optical and electrical properties. The 3b, 3c@MWCNTs LC-intercalated systems (IS) exhibited co-axial distribution of MWCNTs with orderly arrangement showing well-aligned interference colors with banded patterns in the textures, as observed using a polarizing optical microscope. Steady state photoluminescence studies unveiled sharp emission peaks around blue, yellow and red bands, and a broad emission peaks around violet band for 3b, 3c@MWCNTs LC-IS. Further, the Stoke's shifts were observed larger indicating that LC-IS can be used for display applications with high contrast ratio. Fluorescence decay studies demonstrated that average lifetime (τ) was in the range of 0.200ns–0.089ns and 0.087–0.139ns for 3b@MWCNTs and 3c@MWCNTs LC-IS, respectively and were lower than pure 3b, 3c LCs. Due to which it influenced the faster recombination of the excited photons, enabling effective charge transfer rates, and aid in the attainment of quantum equilibrium states quickly in the LC matrix. Furthermore, capacitance-voltage measurements of 3b@MWCNTs LC-IS showed quasi-static complete alignment at 42 °C and 3.2V, however, stable at 10V with relative dielectric permittivity of 0.023. The polarization studies confirmed asymmetric nature of 3b@MWCNTs LC-IS, showing saturation value of 41.8 μC/cm<sup>2</sup> with remnant polarization of 21.4 μC/cm<sup>2</sup>. PFUND studies evidenced that polarization of 3b@MWCNTs LC-IS followed the rate of pulse and the delay at 40 °C and 42 °C with 2V of bias voltage. In contrast, 3c@MWCNTs LC-IS mild reorientation was seen at 2.4V and 7V with breakdown at 10V and polarization didn't follow rate of pulse and delay at any applied voltages. From the reported research work a new pathway has been opened for further exploration of electro-optical properties of various LC molecules, and can serve as a reference to improve electrical and optical properties of LC-IS systems for advanced display applications.</div></div>","PeriodicalId":432,"journal":{"name":"Solid State Sciences","volume":"163 ","pages":"Article 107905"},"PeriodicalIF":3.4,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Phase formation in the GdPO4-YPO4 system has been studied. The samples were synthesized under hydrothermal conditions at a temperature of 503 K and a pressure of approximately 10 MPa for 28 days of isothermal holding. The results of thermal treatment of the obtained samples at 1473 and 1673 K and the results of thermal treatment of GdPO4 at 1873 K are presented. It is shown that in the system, solid solutions Gd1-xYxPO4 are formed based on phases with monoclinic structure GdPO4 and xenotime structure YPO4. The range of existence of two solid solutions at temperatures 503–1473 K lies in the range of compositions from x≈0.20 to x≈0.40. At a temperature of 1673 K, the formation of a phase with anhydrite structure is observed at x≈0.26, and the beginning of transformation of GdPO4 from monoclinic to xenotime structure. Using Knudsen effusion mass spectrometry (KEMS), the qualitative and quantitative composition of the vapor over the (1-x)GdPO4-xYPO4 system has been determined, which consists of a mixture of PO, PO2, and O2. The enthalpy value of the vaporization reaction and the standard formation enthalpies for the GdPO4 and YPO4, as well as the activity of P4O10 in the condensed phase of the (1-x)GdPO4-xYPO4 system, were determined in the temperature range 1650–1850 K.
{"title":"Phase formation under hydrothermal conditions and thermodynamics properties in the GdPO4-YPO4 system","authors":"M.O. Enikeeva , O.V. Proskurina , S.I. Lopatin , V.V. Gusarov","doi":"10.1016/j.solidstatesciences.2025.107899","DOIUrl":"10.1016/j.solidstatesciences.2025.107899","url":null,"abstract":"<div><div>Phase formation in the GdPO<sub>4</sub>-YPO<sub>4</sub> system has been studied. The samples were synthesized under hydrothermal conditions at a temperature of 503 K and a pressure of approximately 10 MPa for 28 days of isothermal holding. The results of thermal treatment of the obtained samples at 1473 and 1673 K and the results of thermal treatment of GdPO<sub>4</sub> at 1873 K are presented. It is shown that in the system, solid solutions Gd<sub>1-<em>x</em></sub>Y<sub><em>x</em></sub>PO<sub>4</sub> are formed based on phases with monoclinic structure GdPO<sub>4</sub> and xenotime structure YPO<sub>4</sub>. The range of existence of two solid solutions at temperatures 503–1473 K lies in the range of compositions from <em>x</em>≈0.20 to <em>x</em>≈0.40. At a temperature of 1673 K, the formation of a phase with anhydrite structure is observed at <em>x</em>≈0.26, and the beginning of transformation of GdPO<sub>4</sub> from monoclinic to xenotime structure. Using Knudsen effusion mass spectrometry (KEMS), the qualitative and quantitative composition of the vapor over the (1-<em>x</em>)GdPO<sub>4</sub>-<em>x</em>YPO<sub>4</sub> system has been determined, which consists of a mixture of PO, PO<sub>2</sub>, and O<sub>2</sub>. The enthalpy value of the vaporization reaction and the standard formation enthalpies for the GdPO<sub>4</sub> and YPO<sub>4</sub>, as well as the activity of P<sub>4</sub>O<sub>10</sub> in the condensed phase of the (1-<em>x</em>)GdPO<sub>4</sub>-<em>x</em>YPO<sub>4</sub> system, were determined in the temperature range 1650–1850 K.</div></div>","PeriodicalId":432,"journal":{"name":"Solid State Sciences","volume":"163 ","pages":"Article 107899"},"PeriodicalIF":3.4,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lutetium aluminum garnet single crystals doped with different concentrations of Eu (0.5, 1.0, 5.0, 10.0, 15.0 %) were grown using the floating zone method, and their optical and scintillation properties were investigated. Several sharp peaks due to 4f-4f transitions of Eu3+ ions were observed at 580–710 nm in photoluminescence (PL) and scintillation spectra, and the PL and scintillation decay times were estimated to be 2.9–3.8 ms. We measured the pulse height spectra under γ-ray irradiation from 137Cs (662 keV) using the setup for scintillators with slow decay times, and the light yields of the samples were estimated. The 5.0 % Eu-doped lutetium aluminum garnet sample showed the highest light yield of 30,000 photons/MeV among the samples.
{"title":"Scintillation properties of Eu3+ doped Lu3Al5O12 single crystals","authors":"Toshiaki Kunikata , Kenichi Watanabe , Hiromi Kimura , Kai Okazaki , Takumi Kato , Daisuke Nakauchi , Noriaki Kawaguchi , Takayuki Yanagida","doi":"10.1016/j.solidstatesciences.2025.107902","DOIUrl":"10.1016/j.solidstatesciences.2025.107902","url":null,"abstract":"<div><div>Lutetium aluminum garnet single crystals doped with different concentrations of Eu (0.5, 1.0, 5.0, 10.0, 15.0 %) were grown using the floating zone method, and their optical and scintillation properties were investigated. Several sharp peaks due to 4f-4f transitions of Eu<sup>3+</sup> ions were observed at 580–710 nm in photoluminescence (PL) and scintillation spectra, and the PL and scintillation decay times were estimated to be 2.9–3.8 ms. We measured the pulse height spectra under γ-ray irradiation from <sup>137</sup>Cs (662 keV) using the setup for scintillators with slow decay times, and the light yields of the samples were estimated. The 5.0 % Eu-doped lutetium aluminum garnet sample showed the highest light yield of 30,000 photons/MeV among the samples.</div></div>","PeriodicalId":432,"journal":{"name":"Solid State Sciences","volume":"163 ","pages":"Article 107902"},"PeriodicalIF":3.4,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143611595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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