Journal of Physics and Chemistry of Solids最新文献_第8页

A steel mesh coated cobalt tungstate microflowers as efficient binder-free electrodes for supercapacitors and oxygen evolution reactions

IF 4.3 3区材料科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Journal of Physics and Chemistry of Solids

Pub Date : 2025-01-19 DOI: 10.1016/j.jpcs.2025.112579

Neha C. Patil , Umesh V. Shembade , Mayuri G. Magadum , Jaywant V. Mane , Dnyandevo N. Zambare , Tanaji R. Bhosale , Annasaheb V. Moholkar , Sandeep B. Wategaonkar

This research successfully synthesized cobalt tungstate (CoWO₄) microflowers on flexible steel mesh (CoW-SM) using the successive ionic layer adsorption and reaction (SILAR) technique for water splitting and energy storage applications. The physicochemical characterization revealed an amorphous structure with a non-uniform, microflower-like (MFs) morphology, which siginifies the better electrochemical performance. Further, X-ray photoelectron spectroscopy (XPS) analysis confirmed the formation of high-purity CoWO₄ Fs. Additionally, the specific surface area (SSA) was determined using N₂ adsorption/desorption, with the optimized sample exhibiting an SSA of 35.4 m²/g and an average pore diameter of 3.24 nm. In contrast to physiochemical analysis, the electrochemical and electrocatalytic investigations were conducted using a three-electrode system. As a result, the (CoWO₄) CoW–C electrode demonstrated exceptional performance, achieving a maximum capacitance (Cs) of 697 F/g and a capacity of 87 mAh/g at a current density of 5 mA/cm². Furthermore, the CoW–C electrode exhibited superior electrocatalytic properties in 1 M KOH, with a low Tafel slope (94 mV/dec), a small overpotential (220 mV), and a high electrochemically active surface area (ECSA) of 78 cm², alongside excellent durability over 5 hours. Therefore, these findings highlight the significant potential of the synthesized CoWO₄ MFs for high-performance supercapacitors and water-splitting applications.

{"title":"A steel mesh coated cobalt tungstate microflowers as efficient binder-free electrodes for supercapacitors and oxygen evolution reactions","authors":"Neha C. Patil , Umesh V. Shembade , Mayuri G. Magadum , Jaywant V. Mane , Dnyandevo N. Zambare , Tanaji R. Bhosale , Annasaheb V. Moholkar , Sandeep B. Wategaonkar","doi":"10.1016/j.jpcs.2025.112579","DOIUrl":"10.1016/j.jpcs.2025.112579","url":null,"abstract":"<div><div>This research successfully synthesized cobalt tungstate (CoWO<sub>4</sub>) microflowers on flexible steel mesh (CoW-SM) using the successive ionic layer adsorption and reaction (SILAR) technique for water splitting and energy storage applications. The physicochemical characterization revealed an amorphous structure with a non-uniform, microflower-like (MFs) morphology, which siginifies the better electrochemical performance. Further, X-ray photoelectron spectroscopy (XPS) analysis confirmed the formation of high-purity CoWO<sub>4</sub> Fs. Additionally, the specific surface area (SSA) was determined using N<sub>2</sub> adsorption/desorption, with the optimized sample exhibiting an SSA of 35.4 m<sup>2</sup>/g and an average pore diameter of 3.24 nm. In contrast to physiochemical analysis, the electrochemical and electrocatalytic investigations were conducted using a three-electrode system. As a result, the (CoWO<sub>4</sub>) CoW–C electrode demonstrated exceptional performance, achieving a maximum capacitance (Cs) of 697 F/g and a capacity of 87 mAh/g at a current density of 5 mA/cm<sup>2</sup>. Furthermore, the CoW–C electrode exhibited superior electrocatalytic properties in 1 M KOH, with a low Tafel slope (94 mV/dec), a small overpotential (220 mV), and a high electrochemically active surface area (ECSA) of 78 cm<sup>2</sup>, alongside excellent durability over 5 hours. Therefore, these findings highlight the significant potential of the synthesized CoWO<sub>4</sub> MFs for high-performance supercapacitors and water-splitting applications.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"200 ","pages":"Article 112579"},"PeriodicalIF":4.3,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101684","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}

引用次数: 0

Analysis of the suppression of the ferroelectric-paraeletric transition and its Curie's temperature in a doped host-structure niobate

IF 4.3 3区材料科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Journal of Physics and Chemistry of Solids

Pub Date : 2025-01-18 DOI: 10.1016/j.jpcs.2025.112578

M.A.L. Nobre , F.R. Praxedes , U.F. Kaneko , F.F. Ivashita , A. Paesano Jr. , S. Lanfredi

Fe-doped potassium-strontium niobate solid solution with centrosymmetric space group was engineered from ferroelectric KSr₂Nb₅O₁₅ host-structure, a classical structure with non-centrosymmetric space-group. A single-phase and crystalline solid solution was prepared via solid state reaction after mechanical mixture of oxides via High Energy Ball Milling. Structural properties of this non-stoichiometric solid solution were investigated by X-ray Diffraction, Raman spectroscopy, X-ray Absorption spectroscopy and Mössbauer spectroscopy. The analyses showed non-isovalent Fe³⁺ cations bi-site substitution on the Nb⁵⁺ cations octahedral sites. The development of a non-ferroelectric state (centrosymmetric) was observed from niobium substitution by Fe³⁺, suppressing ferroelectric-paraelectric phase transition. Further, the absence of Curie's temperature with a non-ferroelectric state was characterized by high-temperature Dielectric spectroscopy, from room temperature up to 965 K. Non-stoichiometric KSr₂(FeNb₄)O_15-δ exhibited semiconductor character with negative temperature coefficient. Centrosymmetric space group and covalent character niobium oxygen bond stemming induction of non-polar ferroelectric configuration are discussed.

{"title":"Analysis of the suppression of the ferroelectric-paraeletric transition and its Curie's temperature in a doped host-structure niobate","authors":"M.A.L. Nobre , F.R. Praxedes , U.F. Kaneko , F.F. Ivashita , A. Paesano Jr. , S. Lanfredi","doi":"10.1016/j.jpcs.2025.112578","DOIUrl":"10.1016/j.jpcs.2025.112578","url":null,"abstract":"<div><div>Fe-doped potassium-strontium niobate solid solution with centrosymmetric space group was engineered from ferroelectric KSr<sub>2</sub>Nb<sub>5</sub>O<sub>15</sub> host-structure, a classical structure with non-centrosymmetric space-group. A single-phase and crystalline solid solution was prepared via solid state reaction after mechanical mixture of oxides via High Energy Ball Milling. Structural properties of this non-stoichiometric solid solution were investigated by X-ray Diffraction, Raman spectroscopy, X-ray Absorption spectroscopy and Mössbauer spectroscopy. The analyses showed non-isovalent Fe<sup>3+</sup> cations bi-site substitution on the Nb<sup>5+</sup> cations octahedral sites. The development of a non-ferroelectric state (centrosymmetric) was observed from niobium substitution by Fe<sup>3+</sup>, suppressing ferroelectric-paraelectric phase transition. Further, the absence of Curie's temperature with a non-ferroelectric state was characterized by high-temperature Dielectric spectroscopy, from room temperature up to 965 K. Non-stoichiometric KSr<sub>2</sub>(FeNb<sub>4</sub>)O<sub>15-δ</sub> exhibited semiconductor character with negative temperature coefficient. Centrosymmetric space group and covalent character niobium oxygen bond stemming induction of non-polar ferroelectric configuration are discussed.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"199 ","pages":"Article 112578"},"PeriodicalIF":4.3,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099506","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}

引用次数: 0

Morphological and surface chemical composition disorder induced efficient oxygen evolution and supercapacitor processes into Co3O4 nanostructures

IF 4.3 3区材料科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Journal of Physics and Chemistry of Solids

Pub Date : 2025-01-18 DOI: 10.1016/j.jpcs.2025.112577

Abdul Jaleel Laghari , Umair Aftab , Muhammad Ishaque Abro , Antonia Infantes-Molina , Zafar Hussain Ibupoto

In this study, a high-efficiency electrode material based on Co₃O₄ was designed. The electrochemical properties were enhanced when orange peel extract was added during the synthesis of Co₃O₄ using modified hydrothermal process. When electrolyzed with 1 M KOH, 10 mL of orange peel extract mediated Co₃O₄ (sample 2) exhibited 310 mV overpotential at 20 mA/cm² and a Tafel slope of 75 mVdec⁻¹. Tests conducted on sample 2 based on Co₃O₄ over a period of 30 h indicated that it was highly durable at different current densities. Among three electrode cells set up in 3 M KOH electrolytic solution, sample 2 of Co₃O₄ displayed a higher specific capacitance of 2021.88 F/g and a higher energy density of 44.93 Wh/Kg at 1.25 A/g. Using sample 2 of Co₃O₄ as an anode material, the ASC device demonstrated a specific capacitance of 1144.0 F/g and an energy density of 24.95 Wh/Kg at 1.25 A/g. Additionally, the specific capacitance retention percentage during 30,000 GCD cycles at 1.25 A/g and the columbic efficiency were estimated to be about 98.6 %. The improved electrochemical activity of sample 2 of Co₃O₄ may be attributed to reduced optical band gaps, altered particle shapes, reduced particle sizes, and abundant oxygen vacancies. Because of its eco-friendly and low-cost characteristics, orange peel extract could be an excellent alternative option for the design of next generation electrode materials for high performance.

{"title":"Morphological and surface chemical composition disorder induced efficient oxygen evolution and supercapacitor processes into Co3O4 nanostructures","authors":"Abdul Jaleel Laghari , Umair Aftab , Muhammad Ishaque Abro , Antonia Infantes-Molina , Zafar Hussain Ibupoto","doi":"10.1016/j.jpcs.2025.112577","DOIUrl":"10.1016/j.jpcs.2025.112577","url":null,"abstract":"<div><div>In this study, a high-efficiency electrode material based on Co<sub>3</sub>O<sub>4</sub> was designed. The electrochemical properties were enhanced when orange peel extract was added during the synthesis of Co<sub>3</sub>O<sub>4</sub> using modified hydrothermal process. When electrolyzed with 1 M KOH, 10 mL of orange peel extract mediated Co<sub>3</sub>O<sub>4</sub> (sample 2) exhibited 310 mV overpotential at 20 mA/cm<sup>2</sup> and a Tafel slope of 75 mVdec<sup>−1</sup>. Tests conducted on sample 2 based on Co<sub>3</sub>O<sub>4</sub> over a period of 30 h indicated that it was highly durable at different current densities. Among three electrode cells set up in 3 M KOH electrolytic solution, sample 2 of Co<sub>3</sub>O<sub>4</sub> displayed a higher specific capacitance of 2021.88 F/g and a higher energy density of 44.93 Wh/Kg at 1.25 A/g. Using sample 2 of Co<sub>3</sub>O<sub>4</sub> as an anode material, the ASC device demonstrated a specific capacitance of 1144.0 F/g and an energy density of 24.95 Wh/Kg at 1.25 A/g. Additionally, the specific capacitance retention percentage during 30,000 GCD cycles at 1.25 A/g and the columbic efficiency were estimated to be about 98.6 %. The improved electrochemical activity of sample 2 of Co<sub>3</sub>O<sub>4</sub> may be attributed to reduced optical band gaps, altered particle shapes, reduced particle sizes, and abundant oxygen vacancies. Because of its eco-friendly and low-cost characteristics, orange peel extract could be an excellent alternative option for the design of next generation electrode materials for high performance.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"199 ","pages":"Article 112577"},"PeriodicalIF":4.3,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099505","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}

引用次数: 0

The role of layer charge on saponite functionalization with a cationic alcoxysilane investigated by physicochemical and electrochemical characterization

IF 4.3 3区材料科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Journal of Physics and Chemistry of Solids

Pub Date : 2025-01-17 DOI: 10.1016/j.jpcs.2025.112566

Anselme Junior Tagne , Liva Dzene , Laure Michelin , Ludovic Josien , Séverinne Rigolet , Gustave Kenne Dedzo , Emmanuel Ngameni

The influence of layer charges of synthetic saponite on its functionalization by a cationic organosilane was investigated for the first time to the best of our knowledge. Saponites of varying layer charges (M^z ⁺ _x/z [Mg₆][Si_8-xAl_x]O₂₀(OH)₄nH₂O, with x = 0.25, 0.5, 1.0 and 2.0) were successfully synthesized by controlled substitution of Si by Al and functionalized by the cationic organosilane (Trimethyl [3-(trimethoxysilyl)propyl] ammonium chloride). The organic compound was mainly located in the interlayer space as indicated by the increase of the d₀₀₁-values of saponite samples after modification. The process was certainly driven by the replacement of the interlayer cations by the cationic alcoxysilane. The optimal grafted amount was obtained with the layer charge 1.0, representing the best compromise between the amount of exchangeable cation and layers’ swelling. The layer charge was also found to structure the alcoxysilane orientation in the interlayer space. Electrochemical characterizations revealed the significant capacity of unmodified saponites to accumulate cations as the layers charge increased. The modified saponites showed poor accumulation of cations and thus suggested that the immobilized alcoxysilanes were not exchangeable. This result demonstrated the effective grafting of the organic compound and highlighted the determinant role of layer charges in the functionalization process.

{"title":"The role of layer charge on saponite functionalization with a cationic alcoxysilane investigated by physicochemical and electrochemical characterization","authors":"Anselme Junior Tagne , Liva Dzene , Laure Michelin , Ludovic Josien , Séverinne Rigolet , Gustave Kenne Dedzo , Emmanuel Ngameni","doi":"10.1016/j.jpcs.2025.112566","DOIUrl":"10.1016/j.jpcs.2025.112566","url":null,"abstract":"<div><div>The influence of layer charges of synthetic saponite on its functionalization by a cationic organosilane was investigated for the first time to the best of our knowledge. Saponites of varying layer charges (M<sup>z</sup> <sup>+</sup> <sub>x/z</sub> [Mg<sub>6</sub>][Si<sub>8-x</sub>Al<sub>x</sub>]O<sub>20</sub>(OH)<sub>4</sub>nH<sub>2</sub>O, with x = 0.25, 0.5, 1.0 and 2.0) were successfully synthesized by controlled substitution of Si by Al and functionalized by the cationic organosilane (Trimethyl [3-(trimethoxysilyl)propyl] ammonium chloride). The organic compound was mainly located in the interlayer space as indicated by the increase of the d<sub>001</sub>-values of saponite samples after modification. The process was certainly driven by the replacement of the interlayer cations by the cationic alcoxysilane. The optimal grafted amount was obtained with the layer charge 1.0, representing the best compromise between the amount of exchangeable cation and layers’ swelling. The layer charge was also found to structure the alcoxysilane orientation in the interlayer space. Electrochemical characterizations revealed the significant capacity of unmodified saponites to accumulate cations as the layers charge increased. The modified saponites showed poor accumulation of cations and thus suggested that the immobilized alcoxysilanes were not exchangeable. This result demonstrated the effective grafting of the organic compound and highlighted the determinant role of layer charges in the functionalization process.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"199 ","pages":"Article 112566"},"PeriodicalIF":4.3,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099517","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}

引用次数: 0

Composite of carboxylized graphene oxide with nanosilica for shale plugging

IF 4.3 3区材料科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Journal of Physics and Chemistry of Solids

Pub Date : 2025-01-17 DOI: 10.1016/j.jpcs.2025.112574

Xinying Cui , Chengwen Wang , Weian Huang , Shifeng Zhang , Haiqun Chen , Bo Wu

Carboxylized graphene oxide (GO-COOH)-silica (SiO₂) composite (GO-COOH/SiO₂) was synthesized in two-steps, and can be applied as plugging additive during drilling operations of shale strata. In the synthetic rout, improved carboxylation method was adopted to have more carboxyl groups grafted on graphene oxide, and nanosilica was synthesized by sol–gel/emulsion technique. The preparation of GO-COOH/SiO₂ composite was achieved by dispersing SiO₂ nanoparticles in GO-COOH solution. XRD and Raman spectroscopy showed that the interlayer spacing of GO-COOH/SiO₂ was 1.36 nm, which was higher than that of GO (0.84 nm) and GO-COOH (0.92 nm). According to SEM and TEM, particle size of synthesized SiO₂ sphere was estimated to be 150 nm, and there were more grown SiO₂ spheres than wrapped SiO₂ particles in the GO-COOH/SiO₂. The more carboxyl groups offers more nano SiO₂ distributed points. Compared to single nanosilica material, the SiO₂ particles in the composite was more evenly distributed and agglomeration was reduced. Plugging properties test results indicated that GO-COOH/SiO₂ composite had better sealing performance than SiO₂, GO and GO-COOH. To evaluate influence of GO-COOH/SiO₂ addition on water-based drilling fluid properties, comparative tests were conducted. The experimental results revealed that introduction of GO-COOH/SiO₂ can reduce filtration loss and enhance plugging capability and thermal tolerance of water-based drilling fluid. Therefore, GO-COOH/SiO₂ can act as a promising nanoplugging additive for shale formation.

{"title":"Composite of carboxylized graphene oxide with nanosilica for shale plugging","authors":"Xinying Cui , Chengwen Wang , Weian Huang , Shifeng Zhang , Haiqun Chen , Bo Wu","doi":"10.1016/j.jpcs.2025.112574","DOIUrl":"10.1016/j.jpcs.2025.112574","url":null,"abstract":"<div><div>Carboxylized graphene oxide (GO-COOH)-silica (SiO<sub>2</sub>) composite (GO-COOH/SiO<sub>2</sub>) was synthesized in two-steps, and can be applied as plugging additive during drilling operations of shale strata. In the synthetic rout, improved carboxylation method was adopted to have more carboxyl groups grafted on graphene oxide, and nanosilica was synthesized by sol–gel/emulsion technique. The preparation of GO-COOH/SiO<sub>2</sub> composite was achieved by dispersing SiO<sub>2</sub> nanoparticles in GO-COOH solution. XRD and Raman spectroscopy showed that the interlayer spacing of GO-COOH/SiO<sub>2</sub> was 1.36 nm, which was higher than that of GO (0.84 nm) and GO-COOH (0.92 nm). According to SEM and TEM, particle size of synthesized SiO<sub>2</sub> sphere was estimated to be 150 nm, and there were more grown SiO<sub>2</sub> spheres than wrapped SiO<sub>2</sub> particles in the GO-COOH/SiO<sub>2</sub>. The more carboxyl groups offers more nano SiO<sub>2</sub> distributed points. Compared to single nanosilica material, the SiO<sub>2</sub> particles in the composite was more evenly distributed and agglomeration was reduced. Plugging properties test results indicated that GO-COOH/SiO<sub>2</sub> composite had better sealing performance than SiO<sub>2</sub>, GO and GO-COOH. To evaluate influence of GO-COOH/SiO<sub>2</sub> addition on water-based drilling fluid properties, comparative tests were conducted. The experimental results revealed that introduction of GO-COOH/SiO<sub>2</sub> can reduce filtration loss and enhance plugging capability and thermal tolerance of water-based drilling fluid. Therefore, GO-COOH/SiO<sub>2</sub> can act as a promising nanoplugging additive for shale formation.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"200 ","pages":"Article 112574"},"PeriodicalIF":4.3,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143101672","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}

引用次数: 0

Demonstrating the substitutional doping of erbium (Er) in BiFeO3 nanoparticles for the enhanced solar-driven photocatalytic activity

IF 4.3 3区材料科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Journal of Physics and Chemistry of Solids

Pub Date : 2025-01-16 DOI: 10.1016/j.jpcs.2025.112573

S. Bharathkumar , Sakar Mohan , Hector Valdes , S. Balakumar

This study reports the synthesis of erbium (Er)-doped bismuth ferrite (BiFeO₃/BFO) nanoparticles at varying molar concentrations (5, 10, and 15 %) using a sol-gel method. X-ray diffraction (XRD) analysis reveals a structural transformation from rhombohedral to orthorhombic upon Er³⁺ doping, confirming the successful incorporation of Er³⁺ ions into the BFO lattice. High-resolution transmission electron microscopy (HRTEM) images show that Er-doping leads to a reduction in particle size and a modification of the surface morphology. The bandgap of the Er-doped BFO samples decreases from 2.34 to 2.15 eV with increasing Er content, attributed to the formation of new Er 4f energy levels within the band structure. The magnetic properties of the samples also improve with increasing Er concentration. Photoluminescence (PL) spectra show reduced PL intensity for the 10 % Er-doped BFO sample, indicating a decrease in recombination rates, while electrochemical impedance spectroscopy (EIS) reveals a reduction in charge transfer resistance. Among the samples, the 10 % Er-doped BFO photocatalyst exhibits the highest photocatalytic efficiency. This enhanced activity is attributed to two key factors: efficient separation and migration of photogenerated charge carriers, and a reduced recombination rate of electron-hole pairs, both driven by the rare-earth doping in BFO. Radical trapping experiments further identify hydroxyl (OH•) radicals as the primary species responsible for photocatalytic degradation. This study provides valuable insights into the tunability of BFO's bandgap energy and photocatalytic properties through Er doping.

{"title":"Demonstrating the substitutional doping of erbium (Er) in BiFeO3 nanoparticles for the enhanced solar-driven photocatalytic activity","authors":"S. Bharathkumar , Sakar Mohan , Hector Valdes , S. Balakumar","doi":"10.1016/j.jpcs.2025.112573","DOIUrl":"10.1016/j.jpcs.2025.112573","url":null,"abstract":"<div><div>This study reports the synthesis of erbium (Er)-doped bismuth ferrite (BiFeO<sub>3</sub>/BFO) nanoparticles at varying molar concentrations (5, 10, and 15 %) using a sol-gel method. X-ray diffraction (XRD) analysis reveals a structural transformation from rhombohedral to orthorhombic upon Er<sup>3+</sup> doping, confirming the successful incorporation of Er<sup>3+</sup> ions into the BFO lattice. High-resolution transmission electron microscopy (HRTEM) images show that Er-doping leads to a reduction in particle size and a modification of the surface morphology. The bandgap of the Er-doped BFO samples decreases from 2.34 to 2.15 eV with increasing Er content, attributed to the formation of new Er 4f energy levels within the band structure. The magnetic properties of the samples also improve with increasing Er concentration. Photoluminescence (PL) spectra show reduced PL intensity for the 10 % Er-doped BFO sample, indicating a decrease in recombination rates, while electrochemical impedance spectroscopy (EIS) reveals a reduction in charge transfer resistance. Among the samples, the 10 % Er-doped BFO photocatalyst exhibits the highest photocatalytic efficiency. This enhanced activity is attributed to two key factors: efficient separation and migration of photogenerated charge carriers, and a reduced recombination rate of electron-hole pairs, both driven by the rare-earth doping in BFO. Radical trapping experiments further identify hydroxyl (OH•) radicals as the primary species responsible for photocatalytic degradation. This study provides valuable insights into the tunability of BFO's bandgap energy and photocatalytic properties through Er doping.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"199 ","pages":"Article 112573"},"PeriodicalIF":4.3,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099519","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}

引用次数: 0

Platinum on nitrogen-doped Mn2O3–NiO as a bifunctional electrocatalyst for air cathodes

IF 4.3 3区材料科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Journal of Physics and Chemistry of Solids

Pub Date : 2025-01-15 DOI: 10.1016/j.jpcs.2025.112575

Ana Mladenović , Yasemin Aykut , Dušan Mladenović , Diogo M.F. Santos , Ayşe Bayrakçeken , Gulin S.P. Soylu , Biljana Šljukić

Designing and developing oxygen electrode bifunctional electrocatalysts to be used in rechargeable metal-air batteries is crucial for their efficient operation. Herein, Mn₂O₃–NiO is synthesised by two different co-precipitation and solid-state reaction methods, and nitrogen is doped into these binary oxides. Subsequently, platinum (Pt) is grafted onto the binary oxide supports, undoped and N-doped, and materials’ structure, texture, surface morphology, and elemental composition/state are examined using XRD, N₂-sorption, TEM, and XPS analysis, respectively. The as-prepared materials were further examined for bifunctional catalysis of oxygen reduction/evolution reactions (ORR/OER). The best-performing Pt/N–Mn₂O₃–NiO (S1) electrocatalyst showed Tafel slope values of 77 and 219 mV dec⁻¹ for ORR and OER, respectively, a number of electrons exchanged during ORR of 3.61 and a diffusion-limited current density of −4.86 mA cm⁻², and finally, the lowest ΔE of 0.92 V. Demonstrated catalytic activity along with the high stability observed during the accelerated stress test make Pt/N–Mn₂O₃–NiO a promising bifunctional ORR/OER electrocatalyst for rechargeable metal-air batteries.

{"title":"Platinum on nitrogen-doped Mn2O3–NiO as a bifunctional electrocatalyst for air cathodes","authors":"Ana Mladenović , Yasemin Aykut , Dušan Mladenović , Diogo M.F. Santos , Ayşe Bayrakçeken , Gulin S.P. Soylu , Biljana Šljukić","doi":"10.1016/j.jpcs.2025.112575","DOIUrl":"10.1016/j.jpcs.2025.112575","url":null,"abstract":"<div><div>Designing and developing oxygen electrode bifunctional electrocatalysts to be used in rechargeable metal-air batteries is crucial for their efficient operation. Herein, Mn<sub>2</sub>O<sub>3</sub>–NiO is synthesised by two different co-precipitation and solid-state reaction methods, and nitrogen is doped into these binary oxides. Subsequently, platinum (Pt) is grafted onto the binary oxide supports, undoped and N-doped, and materials’ structure, texture, surface morphology, and elemental composition/state are examined using XRD, N<sub>2</sub>-sorption, TEM, and XPS analysis, respectively. The as-prepared materials were further examined for bifunctional catalysis of oxygen reduction/evolution reactions (ORR/OER). The best-performing Pt/N–Mn<sub>2</sub>O<sub>3</sub>–NiO (S1) electrocatalyst showed Tafel slope values of 77 and 219 mV dec<sup>−1</sup> for ORR and OER, respectively, a number of electrons exchanged during ORR of 3.61 and a diffusion-limited current density of −4.86 mA cm<sup>−2</sup>, and finally, the lowest ΔE of 0.92 V. Demonstrated catalytic activity along with the high stability observed during the accelerated stress test make Pt/N–Mn<sub>2</sub>O<sub>3</sub>–NiO a promising bifunctional ORR/OER electrocatalyst for rechargeable metal-air batteries.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"199 ","pages":"Article 112575"},"PeriodicalIF":4.3,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099090","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}

引用次数: 0

Computational modeling of non-fullerene donor based on indacenodithiophene with amplified optoelectronic attributes for organic solar cells

IF 4.3 3区材料科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Journal of Physics and Chemistry of Solids

Pub Date : 2025-01-14 DOI: 10.1016/j.jpcs.2025.112571

Adeel Mubarik , Faiza Shafiq , Muhammad Bilal , Nasir Rasool , Ali Raza Ayub , Mostafa A.I. Abdelmotaleb

Over the past decade, organic solar cells (OSCs) using electron-acceptor and electron-donor materials have demonstrated significant potential in advanced optoelectronic applications. We developed seven new organic donor molecules (ID1−ID7) based on highly fused indacenodithiophene by modifying the end group of a reference molecule. Using Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT) with the MPW1PW91 functional, CPCM solvation model, and 6-311G(d,p) basis set, we evaluated the molecules' absorption, excitation, and oscillator strengths. The study assessed key properties, including HOMO/LUMO energy levels, energy gap (E_g), density of states (DOS), dipole moment, transition density matrix (TDM), molecular electrostatic potential (MEP), open-circuit voltage (V_OC), binding energy (E_b), and power conversion efficiency (PCE). The results showed that the new compounds outperformed the reference IDR in photophysical, photovoltaic, and electrical properties. Notably, ID4 excelled with the lowest E_g (1.74 eV), highest λ_max (874 nm), lowest E_x (1.4179 eV), best PCE (15.48 %), high FF (0.90), normalized V_OC (48.73), and absolute V_OC (1.26). These compounds, with their strong electron and hole transport mobilities, are promising for commercial applications. Further research into their properties could enhance the development of efficient photovoltaic organic materials.

{"title":"Computational modeling of non-fullerene donor based on indacenodithiophene with amplified optoelectronic attributes for organic solar cells","authors":"Adeel Mubarik , Faiza Shafiq , Muhammad Bilal , Nasir Rasool , Ali Raza Ayub , Mostafa A.I. Abdelmotaleb","doi":"10.1016/j.jpcs.2025.112571","DOIUrl":"10.1016/j.jpcs.2025.112571","url":null,"abstract":"<div><div>Over the past decade, organic solar cells (OSCs) using electron-acceptor and electron-donor materials have demonstrated significant potential in advanced optoelectronic applications. We developed seven new organic donor molecules (ID1−ID7) based on highly fused indacenodithiophene by modifying the end group of a reference molecule. Using Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT) with the MPW1PW91 functional, CPCM solvation model, and 6-311G(d,p) basis set, we evaluated the molecules' absorption, excitation, and oscillator strengths. The study assessed key properties, including HOMO/LUMO energy levels, energy gap (<em>E</em><sub><em>g</em></sub>), density of states (DOS), dipole moment, transition density matrix (TDM), molecular electrostatic potential (MEP), open-circuit voltage (<em>V</em><sub><em>OC</em></sub>), binding energy (<em>E</em><sub><em>b</em></sub>), and power conversion efficiency (PCE). The results showed that the new compounds outperformed the reference IDR in photophysical, photovoltaic, and electrical properties. Notably, ID4 excelled with the lowest <em>E</em><sub><em>g</em></sub> (1.74 eV), highest <em>λ</em><sub>max</sub> (874 nm), lowest <em>E</em><sub><em>x</em></sub> (1.4179 eV), best PCE (15.48 %), high FF (0.90), normalized <em>V</em><sub><em>OC</em></sub> (48.73), and absolute <em>V</em><sub><em>OC</em></sub> (1.26). These compounds, with their strong electron and hole transport mobilities, are promising for commercial applications. Further research into their properties could enhance the development of efficient photovoltaic organic materials.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"199 ","pages":"Article 112571"},"PeriodicalIF":4.3,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099515","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}

引用次数: 0

Broadband dielectric spectroscopy on dry Poly(vinyl alcohol)/Poly(vinylidene fluoride) blends reinforced with nano - Graphene platelets at combined pressure and temperature

IF 4.3 3区材料科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Journal of Physics and Chemistry of Solids

Pub Date : 2025-01-13 DOI: 10.1016/j.jpcs.2025.112570

Eirini Kolonelou, Anthony N. Papathanassiou

Poly(vinyl alcohol)/Poly(vinylidene fluoride) blends at mass ratio 3:1 with Nano - Graphene Platelet fillers constitute mechanically and thermally stable systems, which are used for developing piezoelectric devices. Blends host a fraction of water molecules absorbed by the poly(vinyl alcohol) phase. Dc conductivity and dielectric relaxation occur via fluctuation induced tunneling of electrons. Electric charge transport is affected by the glass transition of the polymer matrix and the rotational and translational dynamics of absorbed water molecules. In the present work, absorbed water was subtracted by annealing and pumping and, subsequently, dry blends were characterized by employing Broadband Dielectric Spectroscopy at combined temperature and pressure states. Conductivity and relaxation obey fluctuation induced tunneling temperature dependencies. The corresponding activation energies and activation volumes reveal the role of absorbed polar water molecules on the tunneling current for macroscopic or localized electron transport.

{"title":"Broadband dielectric spectroscopy on dry Poly(vinyl alcohol)/Poly(vinylidene fluoride) blends reinforced with nano - Graphene platelets at combined pressure and temperature","authors":"Eirini Kolonelou, Anthony N. Papathanassiou","doi":"10.1016/j.jpcs.2025.112570","DOIUrl":"10.1016/j.jpcs.2025.112570","url":null,"abstract":"<div><div>Poly(vinyl alcohol)/Poly(vinylidene fluoride) blends at mass ratio 3:1 with Nano - Graphene Platelet fillers constitute mechanically and thermally stable systems, which are used for developing piezoelectric devices. Blends host a fraction of water molecules absorbed by the poly(vinyl alcohol) phase. Dc conductivity and dielectric relaxation occur via fluctuation induced tunneling of electrons. Electric charge transport is affected by the glass transition of the polymer matrix and the rotational and translational dynamics of absorbed water molecules. In the present work, absorbed water was subtracted by annealing and pumping and, subsequently, dry blends were characterized by employing Broadband Dielectric Spectroscopy at combined temperature and pressure states. Conductivity and relaxation obey fluctuation induced tunneling temperature dependencies. The corresponding activation energies and activation volumes reveal the role of absorbed polar water molecules on the tunneling current for macroscopic or localized electron transport.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"199 ","pages":"Article 112570"},"PeriodicalIF":4.3,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099520","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}

引用次数: 0

NiVX (X=Si & Ge) Heuslerene: A ferromagnetic semiconductor for thermoelectric and spintronics applications through DFT study

IF 4.3 3区材料科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Journal of Physics and Chemistry of Solids

Pub Date : 2025-01-13 DOI: 10.1016/j.jpcs.2025.112564

S. Monika, G. Suganya, G. Kalpana

The impact of ferromagnetic semiconductors on enhancing the thermoelectric properties of materials was investigated using novel Heuslerene (2D) NiVX (X = Si and Ge). In this study, both bulk and 2D nanosheets of NiVX (X = Si and Ge) were analyzed using the Quantum Espresso code with the ultrasoft pseudopotential approximation. A transition in lattice from FCC in the bulk form to hexagonal in the 2D nanosheets was observed, attributed to the change in dimensionality. The effects of confinement were examined through band structure and density of states, revealing that the nearly half-metallic ferromagnetic behavior of bulk NiVX (X = Si and Ge) transforms into ferromagnetic semiconductor behavior in the 2D nanosheets, with an intrinsic integer magnetic moment of 1.0 μ_B. The mechanical and thermodynamic stability of both bulk and 2D forms of NiVX (X = Si and Ge) was assessed, confirming their robustness.Thermoelectric properties were calculated and compared for bulk and 2D forms using the BoltzTrap code. The 2D nanosheets demonstrated significantly higher ZT values than their bulk counterparts, driven by an enhanced Seebeck coefficient and reduced electronic thermal conductivity. These findings highlight the superior thermoelectric performance of the 2D nanosheets.The combined ferromagnetic and thermoelectric properties of 2D NiVSi and NiVGe underscore their potential as versatile materials for future thermoelectric and spintronic applications.

{"title":"NiVX (X=Si & Ge) Heuslerene: A ferromagnetic semiconductor for thermoelectric and spintronics applications through DFT study","authors":"S. Monika, G. Suganya, G. Kalpana","doi":"10.1016/j.jpcs.2025.112564","DOIUrl":"10.1016/j.jpcs.2025.112564","url":null,"abstract":"<div><div>The impact of ferromagnetic semiconductors on enhancing the thermoelectric properties of materials was investigated using novel Heuslerene (2D) NiVX (X = Si and Ge). In this study, both bulk and 2D nanosheets of NiVX (X = Si and Ge) were analyzed using the Quantum Espresso code with the ultrasoft pseudopotential approximation. A transition in lattice from FCC in the bulk form to hexagonal in the 2D nanosheets was observed, attributed to the change in dimensionality. The effects of confinement were examined through band structure and density of states, revealing that the nearly half-metallic ferromagnetic behavior of bulk NiVX (X = Si and Ge) transforms into ferromagnetic semiconductor behavior in the 2D nanosheets, with an intrinsic integer magnetic moment of 1.0 μ<sub>B</sub>. The mechanical and thermodynamic stability of both bulk and 2D forms of NiVX (X = Si and Ge) was assessed, confirming their robustness.Thermoelectric properties were calculated and compared for bulk and 2D forms using the BoltzTrap code. The 2D nanosheets demonstrated significantly higher ZT values than their bulk counterparts, driven by an enhanced Seebeck coefficient and reduced electronic thermal conductivity. These findings highlight the superior thermoelectric performance of the 2D nanosheets.The combined ferromagnetic and thermoelectric properties of 2D NiVSi and NiVGe underscore their potential as versatile materials for future thermoelectric and spintronic applications.</div></div>","PeriodicalId":16811,"journal":{"name":"Journal of Physics and Chemistry of Solids","volume":"199 ","pages":"Article 112564"},"PeriodicalIF":4.3,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143099521","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}

引用次数: 0