Pub Date : 2022-02-11DOI: 10.1142/s2251237322500010
Zhigang Li, Dou Zhang, Lei Zhang, C. Ruan, Qin Zhou, Y. Lian
Carbon onions (CNOs) are highly desirable in the field of electromagnetic wave absorption (EMWA) due to their onion-like structure, low density and excellent conductivity. Herein nickel encapsulated CNOs were fabricated by arc discharge and then transformed into hollow ones via annealing at 900∘C. The structure and EMWA performance of the hollow and nickel encapsulated CNOs were analyzed in detail to investigate the relationship of their EMWA properties and structure. The better EMWA properties of nickel encapsulated CNOs showed that the core–shell interface contributed more EMMA in comparison to the onion-like configuration.
{"title":"Comparison of the EMWA Performance of Nickel Cored and Hollow Carbon Onions","authors":"Zhigang Li, Dou Zhang, Lei Zhang, C. Ruan, Qin Zhou, Y. Lian","doi":"10.1142/s2251237322500010","DOIUrl":"https://doi.org/10.1142/s2251237322500010","url":null,"abstract":"Carbon onions (CNOs) are highly desirable in the field of electromagnetic wave absorption (EMWA) due to their onion-like structure, low density and excellent conductivity. Herein nickel encapsulated CNOs were fabricated by arc discharge and then transformed into hollow ones via annealing at 900∘C. The structure and EMWA performance of the hollow and nickel encapsulated CNOs were analyzed in detail to investigate the relationship of their EMWA properties and structure. The better EMWA properties of nickel encapsulated CNOs showed that the core–shell interface contributed more EMMA in comparison to the onion-like configuration.","PeriodicalId":16406,"journal":{"name":"Journal of Molecular and Engineering Materials","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44990553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-09DOI: 10.1142/s2251237321500027
Li Feng, Pengyu Wang, Hansen Yang, Zhuo Chen, S. Bo
A charge transfer dye with the D–[Formula: see text]–A structure was synthesized by Pd catalyzed Hartwig–Buchwald coupling and Knoevenagel condensation reaction, using N, N-dihexylbenzo[b]thiophen-6-amine as donor and 2-(3-cyano-4, 5, 5-trimethylfuran-2 (5H)-ylidene)malononitrile (TCF) as acceptor. The solvatochromic and pH switch properties of the as-synthesized dye were investigated through UV-vis absorption and fluorescence emission spectra. A positive solvatochromism of the dye in different polar solvents was observed along with a visible color change of the solution. By adding acid/base into the DMSO solution of the dye, the color as well as the absorption and emission spectra of the solution exhibited outstanding characteristics of pH switch.
{"title":"Solvatochromic and pH Switch Properties of a D–π–A Dye with benzo[b]thiophene as Donor Moiety","authors":"Li Feng, Pengyu Wang, Hansen Yang, Zhuo Chen, S. Bo","doi":"10.1142/s2251237321500027","DOIUrl":"https://doi.org/10.1142/s2251237321500027","url":null,"abstract":"A charge transfer dye with the D–[Formula: see text]–A structure was synthesized by Pd catalyzed Hartwig–Buchwald coupling and Knoevenagel condensation reaction, using N, N-dihexylbenzo[b]thiophen-6-amine as donor and 2-(3-cyano-4, 5, 5-trimethylfuran-2 (5H)-ylidene)malononitrile (TCF) as acceptor. The solvatochromic and pH switch properties of the as-synthesized dye were investigated through UV-vis absorption and fluorescence emission spectra. A positive solvatochromism of the dye in different polar solvents was observed along with a visible color change of the solution. By adding acid/base into the DMSO solution of the dye, the color as well as the absorption and emission spectra of the solution exhibited outstanding characteristics of pH switch.","PeriodicalId":16406,"journal":{"name":"Journal of Molecular and Engineering Materials","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47127178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-20DOI: 10.1142/s2251237321930011
Vikram G. Kamble, P. Mishra, Hassan A. Al Dabbas, H. Panda, Johnathan Bruce Fernandez
For a long time, Aluminum filled epoxies molds have been used in rapid tooling process. These molds are very economical when applied in manufacturing of low volume of plastic parts. To improve the thermal conductivity of the material, the metallic filler material is added to it and the glass fiber improves the wear resistance of the material. These two important parameters establish the life of composites. The present work reports on abrasive wear behavior of Aluminum modified epoxy and glass fiber composite with 5 wt.% and 10 wt.% of aluminum particles. Through pin on disc wear testing machine, we studied the wear behaviors of composites, and all these samples were fabricated by using hand layup process. Epoxy resin was used as matrix material which was reinforced with Glass fiber and Aluminum as filler. The composite with 5 wt.% and 10 wt.% of Al was cast with dimensions 100 × 100 × 6 mm. The specimens were machined to a size of 6 × 6 × 4 mm for abrasive testing. Abrasive tests were carried out for different grit paper sizes, i.e., 150, 320, 600 at different sliding distance, i.e., 20, 40, 60 m at different loads of 5, 10 and 15 N and at constant speed. The weight loss due to wear was calculated along with coefficient of friction. Hardness was found using Rockwell hardness machine. The SEM morphology of the worn out surface wear was analyzed to understand the wear mechanism. Results showed that the addition of Aluminum particles was beneficial for low abrasive conditions.
{"title":"Retraction: Abrasive Wear Performance of Aluminium Modified Epoxy-Glass Fiber Composites","authors":"Vikram G. Kamble, P. Mishra, Hassan A. Al Dabbas, H. Panda, Johnathan Bruce Fernandez","doi":"10.1142/s2251237321930011","DOIUrl":"https://doi.org/10.1142/s2251237321930011","url":null,"abstract":"For a long time, Aluminum filled epoxies molds have been used in rapid tooling process. These molds are very economical when applied in manufacturing of low volume of plastic parts. To improve the thermal conductivity of the material, the metallic filler material is added to it and the glass fiber improves the wear resistance of the material. These two important parameters establish the life of composites. The present work reports on abrasive wear behavior of Aluminum modified epoxy and glass fiber composite with 5 wt.% and 10 wt.% of aluminum particles. Through pin on disc wear testing machine, we studied the wear behaviors of composites, and all these samples were fabricated by using hand layup process. Epoxy resin was used as matrix material which was reinforced with Glass fiber and Aluminum as filler. The composite with 5 wt.% and 10 wt.% of Al was cast with dimensions 100 × 100 × 6 mm. The specimens were machined to a size of 6 × 6 × 4 mm for abrasive testing. Abrasive tests were carried out for different grit paper sizes, i.e., 150, 320, 600 at different sliding distance, i.e., 20, 40, 60 m at different loads of 5, 10 and 15 N and at constant speed. The weight loss due to wear was calculated along with coefficient of friction. Hardness was found using Rockwell hardness machine. The SEM morphology of the worn out surface wear was analyzed to understand the wear mechanism. Results showed that the addition of Aluminum particles was beneficial for low abrasive conditions.","PeriodicalId":16406,"journal":{"name":"Journal of Molecular and Engineering Materials","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48371723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-10DOI: 10.1142/S2251237321500015
Xiulin Yang, Defei Liu, S. Zhong, Xiaofeng Zhou, Kuo‐Wei Huang, Lain‐Jong Li, Z. Lai
Selective conversion of CO2 to formate with high current densities is highly desirable but still challenging. Copper hollow fibers with interconnected pore structures were fabricated via a facile method and used as a stand-alone cathode for highly efficient electrochemical reduction of CO2 to formate. Our studies revealed that delivering the reactant CO2 gas to the inner space of the hollow fiber could build up a higher CO2 partial pressure in the pores and presumably reduce the concentration of H[Formula: see text] from the electrolyte to effectively suppress the major competing reaction, hydrogen evolution reaction (HER), from 46.9% faradaic efficiency (FE) to 15.0%. A high selectivity for CO2 reduction to formate with a maximum FE of 77.1% was achieved with a high current density of 34.7[Formula: see text]mA cm[Formula: see text], which is one of the highest FEs on Cu-based materials. Mechanistic studies suggest that the abundant active sites along with the unique crystal facets induced by the high pressure of CO2 at the pore surface in the “gas in” mode are attributed to the superior electroactivity and selectivity for the CO2 reduction to formate. The Cu hollow fiber electrodes exhibit an outstanding long-term stability at high current density, showing great potential for large-scale practical applications.
高电流密度的CO2选择性转化为甲酸是非常理想的,但仍然具有挑战性。采用简单的方法制备了具有互连孔结构的铜中空纤维,并将其用作独立阴极,用于高效电化学还原CO2生成甲酸。我们的研究表明,将反应物CO2气体输送到中空纤维的内部空间可以在孔隙中建立更高的CO2分压,并可能降低电解质中H的浓度,从而有效地抑制主要的竞争反应——析氢反应(HER),法拉第效率(FE)从46.9%降至15.0%。在34.7 mA cm的高电流密度下,CO2还原生成甲酸的选择性最高达到77.1%,是cu基材料中FEs最高的材料之一。机理研究表明,在“气进”模式下,由于CO2高压在孔隙表面产生了丰富的活性位点和独特的晶体面,这是由于CO2还原生成甲酸的优越电活性和选择性所致。铜空心纤维电极在高电流密度下具有优异的长期稳定性,具有大规模实际应用的潜力。
{"title":"Selective Conversion of Carbon Dioxide to Formate with High Current Densities","authors":"Xiulin Yang, Defei Liu, S. Zhong, Xiaofeng Zhou, Kuo‐Wei Huang, Lain‐Jong Li, Z. Lai","doi":"10.1142/S2251237321500015","DOIUrl":"https://doi.org/10.1142/S2251237321500015","url":null,"abstract":"Selective conversion of CO2 to formate with high current densities is highly desirable but still challenging. Copper hollow fibers with interconnected pore structures were fabricated via a facile method and used as a stand-alone cathode for highly efficient electrochemical reduction of CO2 to formate. Our studies revealed that delivering the reactant CO2 gas to the inner space of the hollow fiber could build up a higher CO2 partial pressure in the pores and presumably reduce the concentration of H[Formula: see text] from the electrolyte to effectively suppress the major competing reaction, hydrogen evolution reaction (HER), from 46.9% faradaic efficiency (FE) to 15.0%. A high selectivity for CO2 reduction to formate with a maximum FE of 77.1% was achieved with a high current density of 34.7[Formula: see text]mA cm[Formula: see text], which is one of the highest FEs on Cu-based materials. Mechanistic studies suggest that the abundant active sites along with the unique crystal facets induced by the high pressure of CO2 at the pore surface in the “gas in” mode are attributed to the superior electroactivity and selectivity for the CO2 reduction to formate. The Cu hollow fiber electrodes exhibit an outstanding long-term stability at high current density, showing great potential for large-scale practical applications.","PeriodicalId":16406,"journal":{"name":"Journal of Molecular and Engineering Materials","volume":"1 1","pages":"2150001"},"PeriodicalIF":1.5,"publicationDate":"2021-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47116328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-01DOI: 10.1142/s2251237321500039
Bellal Sadouki, Hadj Benhebal, B. Benrabah, Abdelmalek Kharroubi
Thin films of Co-doped [Formula: see text]-MnO2 have been deposited on Pyrex glass substrates by the sol–gel dip-coating method with Co concentrations of 1, 3, 5 and 7 at.%. The deposited thin films were characterized for their structural, morphological, optical and electrical properties. The XRD spectra confirm that all the samples have tetragonal phase of [Formula: see text]-MnO2. FTIR spectra reveal the presence of Mn–O in all of the samples. AFM measurements indicate that the surfaces of films have been affected with cobalt content incorporation. Transmittance spectra of the undoped and Co-doped MnO2 thin films were recorded by a UV–vis spectrometer. Optical gap was found to be in the 2.60–2.51-eV scale. This decrease is due to the presence of manganese vacancies and/or oxygen defects. From the complex impedance measurements that show semicircular arcs at different cobalt contents, an equivalent parallel [Formula: see text] electrical circuit has been proposed.
{"title":"Effect of Co Doping on the Functional Properties of MnO2 Thin Films","authors":"Bellal Sadouki, Hadj Benhebal, B. Benrabah, Abdelmalek Kharroubi","doi":"10.1142/s2251237321500039","DOIUrl":"https://doi.org/10.1142/s2251237321500039","url":null,"abstract":"Thin films of Co-doped [Formula: see text]-MnO2 have been deposited on Pyrex glass substrates by the sol–gel dip-coating method with Co concentrations of 1, 3, 5 and 7 at.%. The deposited thin films were characterized for their structural, morphological, optical and electrical properties. The XRD spectra confirm that all the samples have tetragonal phase of [Formula: see text]-MnO2. FTIR spectra reveal the presence of Mn–O in all of the samples. AFM measurements indicate that the surfaces of films have been affected with cobalt content incorporation. Transmittance spectra of the undoped and Co-doped MnO2 thin films were recorded by a UV–vis spectrometer. Optical gap was found to be in the 2.60–2.51-eV scale. This decrease is due to the presence of manganese vacancies and/or oxygen defects. From the complex impedance measurements that show semicircular arcs at different cobalt contents, an equivalent parallel [Formula: see text] electrical circuit has been proposed.","PeriodicalId":16406,"journal":{"name":"Journal of Molecular and Engineering Materials","volume":"1 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44230749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-02-16DOI: 10.1142/s2251237321300011
M. Boutaleb, A. Tadjer
The doping of boron phosphide (BP) with manganese as magnetic impurity at different concentrations provides metallic ferromagnetic materials B[Formula: see text]MnxP at ([Formula: see text], 0.125, 0.0625). Their structural and electronic properties are calculated by the first-principle spin-density functional theory (DFT) within the framework of the Wu–Cohen generalized gradient approximation (WC-GGA). The DMSs BP originated from doping manganese contributed in SP3 hybridization of tetrahedral crystal field caused by the surrounding of four phosphorus anions. These compounds are not half-metallic but exhibit a poorly metallic ferromagnetic nature, the cause is due to the highly covalent chemical bond of BP. The B[Formula: see text]MnxP are metallic ferromagnetic materials and are not to be intended for spintronic industry.
{"title":"Metallic Ferromagnetic Property of Mn-Doped BP Semiconductors","authors":"M. Boutaleb, A. Tadjer","doi":"10.1142/s2251237321300011","DOIUrl":"https://doi.org/10.1142/s2251237321300011","url":null,"abstract":"The doping of boron phosphide (BP) with manganese as magnetic impurity at different concentrations provides metallic ferromagnetic materials B[Formula: see text]MnxP at ([Formula: see text], 0.125, 0.0625). Their structural and electronic properties are calculated by the first-principle spin-density functional theory (DFT) within the framework of the Wu–Cohen generalized gradient approximation (WC-GGA). The DMSs BP originated from doping manganese contributed in SP3 hybridization of tetrahedral crystal field caused by the surrounding of four phosphorus anions. These compounds are not half-metallic but exhibit a poorly metallic ferromagnetic nature, the cause is due to the highly covalent chemical bond of BP. The B[Formula: see text]MnxP are metallic ferromagnetic materials and are not to be intended for spintronic industry.","PeriodicalId":16406,"journal":{"name":"Journal of Molecular and Engineering Materials","volume":"1 1","pages":"2130001"},"PeriodicalIF":1.5,"publicationDate":"2021-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41417622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-10DOI: 10.1142/s2251237320500045
M. Soni, M. Saleem, A. Mishra
The well-known ferroelectric and dielectric materials based on barium titanate (BaTiO3) with the compositional formula Ba[Formula: see text]AEMxTiO3 [[Formula: see text] and AEM (alkaline earth metal) [Formula: see text] Ca and Sr] denoted as BTO, BCTO and BSTO are reported in this work. The solid-state reaction method was used to synthesize these titanates. The as-synthesized samples were characterized for structural elucidation via X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), Raman inelastic scattering, energy dispersive analysis of X-rays (EDAX) and field emission scanning electron microscopy (FESEM). In addition to this, the samples were studied for optical bandgap, dielectric constant, dielectric loss, ac conductivity and polarization ([Formula: see text]–[Formula: see text]) studies. The XRD data analysis revealed that all the samples have acquired a tetragonal structure (P4mm) and are single phased. The Rietveld refinement of Ba[Formula: see text]Ca[Formula: see text]TiO3 confirms XRD results. In FTIR spectra, the absorption modes appearing at about 400[Formula: see text]cm[Formula: see text] and 500[Formula: see text]cm[Formula: see text] are attributes of the vibration of Ti–O bonds and Ba–O bonds, confirming the formation of desired samples. The appearance of the Raman mode of vibration at about 310[Formula: see text]cm[Formula: see text] is an indication of the tetragonal phase. FESEM micrographs of Ba[Formula: see text]Ca[Formula: see text]TiO3 reveal grain growth in the range of about 1[Formula: see text][Formula: see text]m and its EDAX spectrum confirms the composition of the sample. The optical bandgap was found to be 3.35[Formula: see text]eV, 3.1[Formula: see text]eV and 2.65[Formula: see text]eV for pristine, Ca[Formula: see text]- and Sr[Formula: see text]-doped BaTiO3, respectively. Frequency-dependent dielectric studies infer the samples to be extremely good dielectrics in nature with very low loss values. Polarization against a field at 1000[Formula: see text]V witnesses the samples to exhibit low polarization effects with lossy character. The dielectric and [Formula: see text]–[Formula: see text] behavior of Ba[Formula: see text]Sr[Formula: see text]TiO3 was found exceptional among all the reported titanates.
{"title":"A-Site Substituted BaTiO3: Analysis of Structural, Optical, Ferroelectric and Dielectric Nature","authors":"M. Soni, M. Saleem, A. Mishra","doi":"10.1142/s2251237320500045","DOIUrl":"https://doi.org/10.1142/s2251237320500045","url":null,"abstract":"The well-known ferroelectric and dielectric materials based on barium titanate (BaTiO3) with the compositional formula Ba[Formula: see text]AEMxTiO3 [[Formula: see text] and AEM (alkaline earth metal) [Formula: see text] Ca and Sr] denoted as BTO, BCTO and BSTO are reported in this work. The solid-state reaction method was used to synthesize these titanates. The as-synthesized samples were characterized for structural elucidation via X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), Raman inelastic scattering, energy dispersive analysis of X-rays (EDAX) and field emission scanning electron microscopy (FESEM). In addition to this, the samples were studied for optical bandgap, dielectric constant, dielectric loss, ac conductivity and polarization ([Formula: see text]–[Formula: see text]) studies. The XRD data analysis revealed that all the samples have acquired a tetragonal structure (P4mm) and are single phased. The Rietveld refinement of Ba[Formula: see text]Ca[Formula: see text]TiO3 confirms XRD results. In FTIR spectra, the absorption modes appearing at about 400[Formula: see text]cm[Formula: see text] and 500[Formula: see text]cm[Formula: see text] are attributes of the vibration of Ti–O bonds and Ba–O bonds, confirming the formation of desired samples. The appearance of the Raman mode of vibration at about 310[Formula: see text]cm[Formula: see text] is an indication of the tetragonal phase. FESEM micrographs of Ba[Formula: see text]Ca[Formula: see text]TiO3 reveal grain growth in the range of about 1[Formula: see text][Formula: see text]m and its EDAX spectrum confirms the composition of the sample. The optical bandgap was found to be 3.35[Formula: see text]eV, 3.1[Formula: see text]eV and 2.65[Formula: see text]eV for pristine, Ca[Formula: see text]- and Sr[Formula: see text]-doped BaTiO3, respectively. Frequency-dependent dielectric studies infer the samples to be extremely good dielectrics in nature with very low loss values. Polarization against a field at 1000[Formula: see text]V witnesses the samples to exhibit low polarization effects with lossy character. The dielectric and [Formula: see text]–[Formula: see text] behavior of Ba[Formula: see text]Sr[Formula: see text]TiO3 was found exceptional among all the reported titanates.","PeriodicalId":16406,"journal":{"name":"Journal of Molecular and Engineering Materials","volume":"1 1","pages":"2050004"},"PeriodicalIF":1.5,"publicationDate":"2020-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48453380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-08DOI: 10.1142/s2251237320300028
K. Das, Soumyajit Roy
Multi-component hybrid materials are intriguing. They have the potential to act as a platform to manifest the properties of their components. In this review, we discuss the catalytic applications of few such hybrids that are based on oxometalates (OMs). Due to the structural flexibility and enormous properties, OMs are unrivaled in the field of catalysis. Thus, here we primarily focus on the synthesis and catalysis of such OM-based hybrids. The present overview shows that it is possible to improve the catalytic property of bare oxometalates and even that of their soft-matter state namely soft-oxometalates (SOMs) through rational choice of organic ligand and oxometalates.
{"title":"Oxometalate- and Soft-Oxometalate-Based Hybrid Materials: From Synthesis to Catalytic Applications","authors":"K. Das, Soumyajit Roy","doi":"10.1142/s2251237320300028","DOIUrl":"https://doi.org/10.1142/s2251237320300028","url":null,"abstract":"Multi-component hybrid materials are intriguing. They have the potential to act as a platform to manifest the properties of their components. In this review, we discuss the catalytic applications of few such hybrids that are based on oxometalates (OMs). Due to the structural flexibility and enormous properties, OMs are unrivaled in the field of catalysis. Thus, here we primarily focus on the synthesis and catalysis of such OM-based hybrids. The present overview shows that it is possible to improve the catalytic property of bare oxometalates and even that of their soft-matter state namely soft-oxometalates (SOMs) through rational choice of organic ligand and oxometalates.","PeriodicalId":16406,"journal":{"name":"Journal of Molecular and Engineering Materials","volume":"1 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2020-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47907416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-28DOI: 10.1142/s2251237320500057
S. Thiyagarajan, M. Vallejo, P. Ceron, C. Gómez-Solis, C. Wiechers, E. Montes, R. Navarro, M. Sosa
Lithium tetraborate (LTB) was doped with copper (0.1%) to enhance the LTB thermoluminescent (TL) properties. A graphene reducing atmosphere was used to increase the vacancies of oxygen in the crystalline structure. LTB:Cu [Formula: see text] PTFE (polytetrafluoroethylene) pellets were prepared by mixing the Li2B4O7:Cu with PTFE in a 4:1 ratio. The obtained materials were characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). Crystals of Li2B4O7 with the average size of 134[Formula: see text]nm were obtained. The presence of copper was confirmed by SEM. The TL response of LTB:Cu PTFE pellets was studied with [Formula: see text] radiation by using a [Formula: see text]Co source. TTL response shows a linear behavior depending on the radiation dose. The effect of annealing time on TL glow curve was analyzed from 2[Formula: see text]h to 10[Formula: see text]h by irradiating with X-rays. The effect of mass on the TL response was studied varying the mass of the sample from 10[Formula: see text]mg to 50[Formula: see text]mg. From various heating rate studies, it was observed that the TL intensity increased when heating rate was gradually increased. The kinetic parameters were calculated by using computer deconvolution methods. The dosimetric property results showed that this material could have good potential application in a radiation dosimeter for radiation therapy treatment in the medical field.
{"title":"Thermoluminescence of Cu-Doped Li2B4O7+PTFE Annealed by Graphene Exposed to X-Rays and Gamma Radiation","authors":"S. Thiyagarajan, M. Vallejo, P. Ceron, C. Gómez-Solis, C. Wiechers, E. Montes, R. Navarro, M. Sosa","doi":"10.1142/s2251237320500057","DOIUrl":"https://doi.org/10.1142/s2251237320500057","url":null,"abstract":"Lithium tetraborate (LTB) was doped with copper (0.1%) to enhance the LTB thermoluminescent (TL) properties. A graphene reducing atmosphere was used to increase the vacancies of oxygen in the crystalline structure. LTB:Cu [Formula: see text] PTFE (polytetrafluoroethylene) pellets were prepared by mixing the Li2B4O7:Cu with PTFE in a 4:1 ratio. The obtained materials were characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). Crystals of Li2B4O7 with the average size of 134[Formula: see text]nm were obtained. The presence of copper was confirmed by SEM. The TL response of LTB:Cu PTFE pellets was studied with [Formula: see text] radiation by using a [Formula: see text]Co source. TTL response shows a linear behavior depending on the radiation dose. The effect of annealing time on TL glow curve was analyzed from 2[Formula: see text]h to 10[Formula: see text]h by irradiating with X-rays. The effect of mass on the TL response was studied varying the mass of the sample from 10[Formula: see text]mg to 50[Formula: see text]mg. From various heating rate studies, it was observed that the TL intensity increased when heating rate was gradually increased. The kinetic parameters were calculated by using computer deconvolution methods. The dosimetric property results showed that this material could have good potential application in a radiation dosimeter for radiation therapy treatment in the medical field.","PeriodicalId":16406,"journal":{"name":"Journal of Molecular and Engineering Materials","volume":"1 1","pages":"2050005"},"PeriodicalIF":1.5,"publicationDate":"2020-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1142/s2251237320500057","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45484392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-03DOI: 10.1142/s2251237320300016
Matej Sebek, A. Elbana, A. Nemati, Jisheng Pan, Z. Shen, M. Hong, X. Su, N. Thanh, J. Teng
The inherent thinness of two-dimensional 2D materials limits their efficiency of light-matter interactions and the high loss of noble metal plasmonic nanostructures limits their applicability. Thus...
{"title":"Hybrid Plasmonics and Two-Dimensional Materials: Theory and Applications","authors":"Matej Sebek, A. Elbana, A. Nemati, Jisheng Pan, Z. Shen, M. Hong, X. Su, N. Thanh, J. Teng","doi":"10.1142/s2251237320300016","DOIUrl":"https://doi.org/10.1142/s2251237320300016","url":null,"abstract":"The inherent thinness of two-dimensional 2D materials limits their efficiency of light-matter interactions and the high loss of noble metal plasmonic nanostructures limits their applicability. Thus...","PeriodicalId":16406,"journal":{"name":"Journal of Molecular and Engineering Materials","volume":"08 1","pages":"2030001"},"PeriodicalIF":1.5,"publicationDate":"2020-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1142/s2251237320300016","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43243069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}