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Materials, Volume 10, Issue 11 (November 2017)

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Cover Story (view full-size image) The cover image depicts the results of a new approach to model particle–wall interactions that [...] Read more.
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Open AccessArticle Analysis of the Shear Behavior of Stubby Y-Type Perfobond Rib Shear Connectors for a Composite Frame Structure
Materials 2017, 10(11), 1340; https://doi.org/10.3390/ma10111340
Received: 27 October 2017 / Revised: 14 November 2017 / Accepted: 14 November 2017 / Published: 22 November 2017
Cited by 1 | PDF Full-text (5301 KB) | HTML Full-text | XML Full-text
Abstract
Shear connectors are used in steel beam–concrete slabs of composite frame and bridge structures to transfer shear force according to design loads. The existing Y-type perfobond rib shear connectors are designed for girder slabs of composite bridges. Therefore, the rib and transverse rebars
[...] Read more.
Shear connectors are used in steel beam–concrete slabs of composite frame and bridge structures to transfer shear force according to design loads. The existing Y-type perfobond rib shear connectors are designed for girder slabs of composite bridges. Therefore, the rib and transverse rebars of the conventional Y-type perfobond rib shear connectors are extremely large for the composite frames of building structures. Thus, this paper proposes stubby Y-type perfobond rib shear connectors, redefining the existing connectors, for composite frames of building structures; these were used to perform push-out tests. These shear connectors have relatively small ribs compared to the conventional Y-type perfobond rib shear connectors. To confirm the shear resistance of these stubby shear connectors, we performed an experiment by using transverse rebars D13 and D16. The results indicate that these shear connectors have suitable shear strength and ductility for application in composite frame structures. The shear strengths obtained using D13 and D16 were not significantly different. However, the ductility of the shear connectors with D16 was 45.1% higher than that of the shear connectors with D13. Full article
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Open AccessArticle Environmentally Friendly Compatibilizers from Soybean Oil for Ternary Blends of Poly(lactic acid)-PLA, Poly(ε-caprolactone)-PCL and Poly(3-hydroxybutyrate)-PHB
Materials 2017, 10(11), 1339; https://doi.org/10.3390/ma10111339
Received: 2 November 2017 / Revised: 17 November 2017 / Accepted: 20 November 2017 / Published: 22 November 2017
Cited by 1 | PDF Full-text (9068 KB) | HTML Full-text | XML Full-text
Abstract
Ternary blends of poly(lactic acid) (PLA), poly(3-hydroxybutyrate) (PHB) and poly(ε-caprolactone) (PCL) with a constant weight percentage of 60%, 10% and 30% respectively were compatibilized with soybean oil derivatives epoxidized soybean oil (ESO), maleinized soybean oil (MSO) and acrylated epoxidized soybean oil (AESO). The
[...] Read more.
Ternary blends of poly(lactic acid) (PLA), poly(3-hydroxybutyrate) (PHB) and poly(ε-caprolactone) (PCL) with a constant weight percentage of 60%, 10% and 30% respectively were compatibilized with soybean oil derivatives epoxidized soybean oil (ESO), maleinized soybean oil (MSO) and acrylated epoxidized soybean oil (AESO). The potential compatibilization effects of the soybean oil-derivatives was characterized in terms of mechanical, thermal and thermomechanical properties. The effects on morphology were studied by field emission scanning electron microscopy (FESEM). All three soybean oil-based compatibilizers led to a noticeable increase in toughness with a remarkable improvement in elongation at break. On the other hand, both the tensile modulus and strength decreased, but in a lower extent to a typical plasticization effect. Although phase separation occurred, all three soybean oil derivatives led somewhat to compatibilization through reaction between terminal hydroxyl groups in all three biopolyesters (PLA, PHB and PCL) and the readily reactive groups in the soybean oil derivatives, that is, epoxy, maleic anhydride and acrylic/epoxy functionalities. In particular, the addition of 5 parts per hundred parts of the blend (phr) of ESO gave the maximum elongation at break while the same amount of MSO and AESO gave the maximum toughness, measured through Charpy’s impact tests. In general, the herein-developed materials widen the potential of ternary PLA formulations by a cost effective blending method with PHB and PCL and compatibilization with vegetable oil-based additives. Full article
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Open AccessArticle Auxeticity of Yukawa Systems with Nanolayers in the (111) Crystallographic Plane
Materials 2017, 10(11), 1338; https://doi.org/10.3390/ma10111338
Received: 31 October 2017 / Revised: 16 November 2017 / Accepted: 17 November 2017 / Published: 22 November 2017
Cited by 4 | PDF Full-text (5084 KB) | HTML Full-text | XML Full-text
Abstract
Elastic properties of model crystalline systems, in which the particles interact via the hard potential (infinite when any particles overlap and zero otherwise) and the hard-core repulsive Yukawa interaction, were determined by Monte Carlo simulations. The influence of structural modifications, in the form
[...] Read more.
Elastic properties of model crystalline systems, in which the particles interact via the hard potential (infinite when any particles overlap and zero otherwise) and the hard-core repulsive Yukawa interaction, were determined by Monte Carlo simulations. The influence of structural modifications, in the form of periodic nanolayers being perpendicular to the crystallographic axis [111], on auxetic properties of the crystal was investigated. It has been shown that the hard sphere nanolayers introduced into Yukawa crystals allow one to control the elastic properties of the system. It has been also found that the introduction of the Yukawa monolayers to the hard sphere crystal induces auxeticity in the [ 11 1 ¯ ] [ 112 ] -direction, while maintaining the negative Poisson’s ratio in the [ 110 ] [ 1 1 ¯ 0 ] -direction, thus expanding the partial auxeticity of the system to an additional important crystallographic direction. Full article
(This article belongs to the Special Issue Auxetic Materials 2017)
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Open AccessFeature PaperArticle In-Doped ZnO Hexagonal Stepped Nanorods and Nanodisks as Potential Scaffold for Highly-Sensitive Phenyl Hydrazine Chemical Sensors
Materials 2017, 10(11), 1337; https://doi.org/10.3390/ma10111337
Received: 26 October 2017 / Revised: 17 November 2017 / Accepted: 18 November 2017 / Published: 21 November 2017
Cited by 1 | PDF Full-text (3540 KB) | HTML Full-text | XML Full-text
Abstract
Herein, we report the growth of In-doped ZnO (IZO) nanomaterials, i.e., stepped hexagonal nanorods and nanodisks by the thermal evaporation process using metallic zinc and indium powders in the presence of oxygen. The as-grown IZO nanomaterials were investigated by several techniques in order
[...] Read more.
Herein, we report the growth of In-doped ZnO (IZO) nanomaterials, i.e., stepped hexagonal nanorods and nanodisks by the thermal evaporation process using metallic zinc and indium powders in the presence of oxygen. The as-grown IZO nanomaterials were investigated by several techniques in order to examine their morphological, structural, compositional and optical properties. The detailed investigations confirmed that the grown nanomaterials, i.e., nanorods and nanodisks possess well-crystallinity with wurtzite hexagonal phase and grown in high density. The room-temperature PL spectra exhibited a suppressed UV emissions with strong green emissions for both In-doped ZnO nanomaterials, i.e., nanorods and nanodisks. From an application point of view, the grown IZO nanomaterials were used as a potential scaffold to fabricate sensitive phenyl hydrazine chemical sensors based on the I–V technique. The observed sensitivities of the fabricated sensors based on IZO nanorods and nanodisks were 70.43 μA·mM−1·cm−2 and 130.18 μA·mM−1·cm−2, respectively. For both the fabricated sensors, the experimental detection limit was 0.5 μM, while the linear range was 0.5 μM–5.0 mM. The observed results revealed that the simply grown IZO nanomaterials could efficiently be used to fabricate highly sensitive chemical sensors. Full article
(This article belongs to the Special Issue Zinc Oxide Nanostructures: Synthesis and Characterization)
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Open AccessArticle Multifunctional Carbon Aerogels Derived by Sol–Gel Process of Natural Polysaccharides of Different Botanical Origin
Materials 2017, 10(11), 1336; https://doi.org/10.3390/ma10111336
Received: 18 October 2017 / Revised: 3 November 2017 / Accepted: 17 November 2017 / Published: 21 November 2017
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Abstract
In this manuscript, we describe the results of our recent studies on carbon aerogels derived from natural starches. A facile method for the fabrication of carbon aerogels is presented. Moreover, the complete analysis of the carbonization process of different starch aerogels (potato, maize,
[...] Read more.
In this manuscript, we describe the results of our recent studies on carbon aerogels derived from natural starches. A facile method for the fabrication of carbon aerogels is presented. Moreover, the complete analysis of the carbonization process of different starch aerogels (potato, maize, and rice) was performed using thermogravimetric studies combined with a detailed analysis of evolved decomposition products. The prepared carbon aerogels were studied in terms of their morphology and electrical properties to relate the origin of starch precursor with final properties of carbon materials. The obtained results confirmed the differences in carbon aerogels’ morphology, especially in materials’ specific surface areas, depending on the botanical origin of precursors. The electrical conductivity measurements suggest that carbon aerogels with the best electrical properties can be obtained from potato starch. Full article
(This article belongs to the Special Issue Novel Electrochemical Materials for Energy Storage and Conversion)
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Open AccessFeature PaperArticle Time-Resolved Photoluminescence Microscopy for the Analysis of Semiconductor-Based Paint Layers
Materials 2017, 10(11), 1335; https://doi.org/10.3390/ma10111335
Received: 29 September 2017 / Revised: 9 November 2017 / Accepted: 18 November 2017 / Published: 21 November 2017
Cited by 1 | PDF Full-text (8828 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In conservation, science semiconductors occur as the constituent matter of the so-called semiconductor pigments, produced following the Industrial Revolution and extensively used by modern painters. With recent research highlighting the occurrence of various degradation phenomena in semiconductor paints, it is clear that their
[...] Read more.
In conservation, science semiconductors occur as the constituent matter of the so-called semiconductor pigments, produced following the Industrial Revolution and extensively used by modern painters. With recent research highlighting the occurrence of various degradation phenomena in semiconductor paints, it is clear that their detection by conventional optical fluorescence imaging and microscopy is limited by the complexity of historical painting materials. Here, we illustrate and prove the capabilities of time-resolved photoluminescence (TRPL) microscopy, equipped with both spectral and lifetime sensitivity at timescales ranging from nanoseconds to hundreds of microseconds, for the analysis of cross-sections of paint layers made of luminescent semiconductor pigments. The method is sensitive to heterogeneities within micro-samples and provides valuable information for the interpretation of the nature of the emissions in samples. A case study is presented on micro samples from a painting by Henri Matisse and serves to demonstrate how TRPL can be used to identify the semiconductor pigments zinc white and cadmium yellow, and to inform future investigations of the degradation of a cadmium yellow paint. Full article
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Open AccessArticle Underlying Physics of Conductive Polymer Composites and Force Sensing Resistors (FSRs). A Study on Creep Response and Dynamic Loading
Materials 2017, 10(11), 1334; https://doi.org/10.3390/ma10111334
Received: 26 October 2017 / Revised: 9 November 2017 / Accepted: 15 November 2017 / Published: 21 November 2017
Cited by 1 | PDF Full-text (14017 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Force Sensing Resistors (FSRs) are manufactured by sandwiching a Conductive Polymer Composite (CPC) between metal electrodes. The piezoresistive property of FSRs has been exploited to perform stress and strain measurements, but the rheological property of polymers has undermined the repeatability of measurements causing
[...] Read more.
Force Sensing Resistors (FSRs) are manufactured by sandwiching a Conductive Polymer Composite (CPC) between metal electrodes. The piezoresistive property of FSRs has been exploited to perform stress and strain measurements, but the rheological property of polymers has undermined the repeatability of measurements causing creep in the electrical resistance of FSRs. With the aim of understanding the creep phenomenon, the drift response of thirty two specimens of FSRs was studied using a statistical approach. Similarly, a theoretical model for the creep response was developed by combining the Burger’s rheological model with the equations for the quantum tunneling conduction through thin insulating films. The proposed model and the experimental observations showed that the sourcing voltage has a strong influence on the creep response; this observation—and the corresponding model—is an important contribution that has not been previously accounted. The phenomenon of sensitivity degradation was also studied. It was found that sensitivity degradation is a voltage-related phenomenon that can be avoided by choosing an appropriate sourcing voltage in the driving circuit. The models and experimental observations from this study are key aspects to enhance the repeatability of measurements and the accuracy of FSRs. Full article
(This article belongs to the Section Advanced Composites)
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Open AccessArticle Residual Endodontic Filling Material after Post Space Preparation: A Confocal Microscopic Study
Materials 2017, 10(11), 1333; https://doi.org/10.3390/ma10111333
Received: 13 September 2017 / Revised: 9 November 2017 / Accepted: 16 November 2017 / Published: 21 November 2017
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Abstract
This laboratory study assessed removability of endodontic alkaline cements and resin sealers using coronal cross-sectional slices of roots with single canals. Materials were labelled with 0.1% (w/w) sodium fluorescein prior to mixing so that confocal microscopy could be used
[...] Read more.
This laboratory study assessed removability of endodontic alkaline cements and resin sealers using coronal cross-sectional slices of roots with single canals. Materials were labelled with 0.1% (w/w) sodium fluorescein prior to mixing so that confocal microscopy could be used to quantify material remaining on the walls of post spaces, to assess cleanliness. Roots of extracted teeth were prepared using rotary NiTi instruments then obturated using lateral condensation with gutta percha and epoxy resin sealers (AH-Plus™ or Zirmix™), or were filled by injecting mineral trioxide aggregate (MTA) cement (GC Nex™ MTA or MTAmix™) or a hard-setting calcium hydroxide cement (Supercal™). Brown (#3) ParaPost™ drills were used at 600 rpm with a torque setting of 3 N cm−1 for 2 min to remove 5 mm of the root filling. Roots were embedded and coronal slices examined by confocal microscopy, with the perimeter of the drill channel divided into clean, unclean and non-accessible regions. The choice of material affects cleanliness, with MTA being the most difficult and calcium hydroxide cement the easiest to remove. With epoxy resin-based sealers, almost half of the accessible canal walls remained coated with remnants of sealer after post space preparation. Full article
(This article belongs to the Special Issue Dental Biomaterials 2017)
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Open AccessArticle Solution Growth of Two-Dimensional Bi2Se3 Nanosheets for Two-Color All-Optical Switching
Materials 2017, 10(11), 1332; https://doi.org/10.3390/ma10111332
Received: 27 October 2017 / Revised: 14 November 2017 / Accepted: 18 November 2017 / Published: 21 November 2017
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Abstract
Two-dimensional Bi2Se3 nanosheets with hexagonal shape are synthesized by a solution synthetic route. The Bi2Se3 nanosheets are 120 nm in edge width and 7 nm in thickness. The size of the Bi2Se3 nanosheets can
[...] Read more.
Two-dimensional Bi2Se3 nanosheets with hexagonal shape are synthesized by a solution synthetic route. The Bi2Se3 nanosheets are 120 nm in edge width and 7 nm in thickness. The size of the Bi2Se3 nanosheets can be controlled by choosing different kinds of reducing agents including hydroxylamine and ethylenediamine. Subsequently, we demonstrate a configuration of two-color all-optical switching based on plasma channels effect using the as-synthesized Bi2Se3 nanosheets as an optical media. The signal light can be modulated as two states including dot and ring shape by changing the intensity of control light. The modulated signal light exhibits excellent spatial propagation properties. As a type of interesting optical material, ultrathin two-dimensional Bi2Se3 nanosheets might provide an effective option for photoelectric applications. Full article
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Open AccessCommunication Warm Pre-Strain: Strengthening the Metastable 304L Austenitic Stainless Steel without Compromising Its Hydrogen Embrittlement Resistance
Materials 2017, 10(11), 1331; https://doi.org/10.3390/ma10111331
Received: 12 October 2017 / Revised: 13 November 2017 / Accepted: 17 November 2017 / Published: 21 November 2017
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Abstract
Plastic pre-strains were applied to the metastable 304L austenitic stainless steel at both room temperature (20 °C) and higher temperatures (i.e., 50, 80 and 100 °C), and then the hydrogen embrittlement (HE) susceptibility of the steel was evaluated by cathodically hydrogen-charging and tensile
[...] Read more.
Plastic pre-strains were applied to the metastable 304L austenitic stainless steel at both room temperature (20 °C) and higher temperatures (i.e., 50, 80 and 100 °C), and then the hydrogen embrittlement (HE) susceptibility of the steel was evaluated by cathodically hydrogen-charging and tensile testing. The 20 °C pre-strain greatly strengthened the steel, but simultaneously significantly increased the HE susceptibility of the steel, since α′ martensite was induced by the pre-strain, causing the pre-existence of α′ martensite, which provided “highways” for hydrogen to transport deep into the steel during the hydrogen-charging. Although the warm pre-strains did not strengthen the steel as significantly as the 20 °C pre-strain, they retained the HE resistance of the steel. This is because the higher temperatures, particularly 80 and 100 °C, suppressed the α′ martensite transformation during the pre-straining. Pre-strain at a temperature slightly higher than room temperature has a potential to strengthen the metastable 304L austenitic stainless steel without compromising its initial HE resistance. Full article
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Open AccessArticle Facile Control of the Porous Structure of Larch-Derived Mesoporous Carbons via Self-Assembly for Supercapacitors
Materials 2017, 10(11), 1330; https://doi.org/10.3390/ma10111330
Received: 26 October 2017 / Revised: 16 November 2017 / Accepted: 17 November 2017 / Published: 20 November 2017
Cited by 1 | PDF Full-text (3784 KB) | HTML Full-text | XML Full-text
Abstract
Mesoporous carbons have been successfully synthesized via self-assembly using larch-based resins as precursors and triblock copolymers as soft templates. The porous structure of mesoporous carbons can be tailored by adjusting the ratio of hydrophilic/hydrophobic (EO/PO) units owing to interfacial curvature. Interestingly, the porous
[...] Read more.
Mesoporous carbons have been successfully synthesized via self-assembly using larch-based resins as precursors and triblock copolymers as soft templates. The porous structure of mesoporous carbons can be tailored by adjusting the ratio of hydrophilic/hydrophobic (EO/PO) units owing to interfacial curvature. Interestingly, the porous structures show a distinct change from vortex-like to worm-like pores, to stripe-like pores, and to ordered two-dimensional hexagonal pores as the ratio of hydrophilic/hydrophobic units increases, indicating the significant effect of EO/PO ratio on the porous structure. The mesoporous carbons as supercapacitor electrodes exhibit superior electrochemical capacitive performance and a high degree of reversibility after 2000 cycles for supercapacitors due to the well-defined mesoporosity of the carbon materials. Meanwhile, the superior carbon has a high specific capacitance of 107 F·g−1 in 6 M KOH at a current density of 10 A·g−1. Full article
(This article belongs to the Section Porous Materials)
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Open AccessCommunication Morphology and Mechanical Properties of Polyimide Films: The Effects of UV Irradiation on Microscale Surface
Materials 2017, 10(11), 1329; https://doi.org/10.3390/ma10111329
Received: 25 October 2017 / Revised: 17 November 2017 / Accepted: 17 November 2017 / Published: 20 November 2017
Cited by 1 | PDF Full-text (2654 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
As an attractive dielectric material, polyimide has been widely used in the field of electronics, aerospace, and automobiles due to its useful mechanical properties and good chemical resistance. UV irradiation was considered to be the main factor related to the damage and failure
[...] Read more.
As an attractive dielectric material, polyimide has been widely used in the field of electronics, aerospace, and automobiles due to its useful mechanical properties and good chemical resistance. UV irradiation was considered to be the main factor related to the damage and failure of polyimide. Here the effects of UV irradiation on the surface morphology and microscale mechanical properties of polyimide films are characterized by atomic force microscopy (AFM). The surface roughness of the UV-irradiated samples developed and the mechanical properties degraded with the radiation dose increased. For comparison, uniaxial tensile test was performed to obtain the macroscale Young’s modulus of polyimide film. The UV-irradiated damaging depth was simulated with finite element method (FEM). Full article
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Open AccessArticle Tuning the Photoluminescence of Graphene Quantum Dots by Photochemical Doping with Nitrogen
Materials 2017, 10(11), 1328; https://doi.org/10.3390/ma10111328
Received: 28 September 2017 / Revised: 31 October 2017 / Accepted: 14 November 2017 / Published: 20 November 2017
Cited by 2 | PDF Full-text (1577 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Nitrogen-doped graphene quantum dots (NGQDs) were synthesized by irradiating graphene quantum dots (GQDs) in an NH3 atmosphere. The photoluminescence (PL) properties of the GQDs and the NGQDs samples were investigated. Compared with GQDs, a clear PL blue-shift of NGQDs could be achieved
[...] Read more.
Nitrogen-doped graphene quantum dots (NGQDs) were synthesized by irradiating graphene quantum dots (GQDs) in an NH3 atmosphere. The photoluminescence (PL) properties of the GQDs and the NGQDs samples were investigated. Compared with GQDs, a clear PL blue-shift of NGQDs could be achieved by regulating the irradiating time. The NGQDs obtained by irradiation of GQDs for 70 min had a high N content of 15.34 at % and a PL blue-shift of about 47 nm. This may be due to the fact that photochemical doping of GQDs with nitrogen can significantly enhance the contents of pyridine-like nitrogen, and also effectively decrease the contents of oxygen functional groups of NGQDs, thus leading to the observed obvious PL blue-shift. Full article
(This article belongs to the Special Issue Luminescent Materials 2017)
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Open AccessArticle Structural, Electrical, Magnetic and Resistive Switching Properties of the Multiferroic/Ferroelectric Bilayer Thin Films
Materials 2017, 10(11), 1327; https://doi.org/10.3390/ma10111327
Received: 5 October 2017 / Revised: 3 November 2017 / Accepted: 15 November 2017 / Published: 20 November 2017
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Abstract
Bi0.8Pr0.2Fe0.95Mn0.05O3/Bi3.96Gd0.04Ti2.95W0.05O12 (BPFMO/BGTWO) bilayer thin films with Multiferroic/Ferroelectric (MF/FE) structures were deposited onto Pt(111)/Ti/SiO2/Si(100) substrates by using the sol-gel method with rapid thermal
[...] Read more.
Bi0.8Pr0.2Fe0.95Mn0.05O3/Bi3.96Gd0.04Ti2.95W0.05O12 (BPFMO/BGTWO) bilayer thin films with Multiferroic/Ferroelectric (MF/FE) structures were deposited onto Pt(111)/Ti/SiO2/Si(100) substrates by using the sol-gel method with rapid thermal annealing. The BPFMO/BGTWO thin films exhibited well-saturated ferromagnetic and ferroelectric hysteresis loops because of the electro-magnetic coupling induced by the MF/FE structure. The remnant magnetization (2Mr) and remnant polarization (2Pr) were 4.6 emu/cm3 and 62 μC/cm2, respectively. Moreover, the bipolar I-V switching curves of BPFMO/BGTWO bilayer thin films resistive random access memory (RRAM) devices were discussed, and investigated for LRS/HRS. Full article
(This article belongs to the Special Issue Stretchable and Flexible Electronic Materials & Devices)
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Open AccessArticle Novel Montmorillonite/TiO2/MnAl-Mixed Oxide Composites Prepared from Inverse Microemulsions as Combustion Catalysts
Materials 2017, 10(11), 1326; https://doi.org/10.3390/ma10111326
Received: 30 October 2017 / Revised: 17 November 2017 / Accepted: 17 November 2017 / Published: 19 November 2017
Cited by 1 | PDF Full-text (3100 KB) | HTML Full-text | XML Full-text
Abstract
A novel design of combustion catalysts is proposed, in which clay/TiO2/MnAl-mixed oxide composites are formed by intermixing exfoliated organo-montmorillonite with oxide precursors (hydrotalcite-like in the case of Mn-Al oxide) obtained by an inverse microemulsion method. In order to assess the catalysts’
[...] Read more.
A novel design of combustion catalysts is proposed, in which clay/TiO2/MnAl-mixed oxide composites are formed by intermixing exfoliated organo-montmorillonite with oxide precursors (hydrotalcite-like in the case of Mn-Al oxide) obtained by an inverse microemulsion method. In order to assess the catalysts’ thermal stability, two calcination temperatures were employed: 450 and 600 °C. The composites were characterized with XRF (X-ray fluorescence), XRD (X-ray diffraction), HR SEM (high resolution scanning electron microscopy, N2 adsorption/desorption at −196 °C, and H2 TPR (temperature programmed reduction). Profound differences in structural, textural and redox properties of the materials were observed, depending on the presence of the TiO2 component, the type of neutralization agent used in the titania nanoparticles preparation (NaOH or NH3 (aq)), and the temperature of calcination. Catalytic tests of toluene combustion revealed that the clay/TiO2/MnAl-mixed oxide composites prepared with the use of ammonia showed excellent activity, the composites obtained from MnAl hydrotalcite nanoparticles trapped between the organoclay layers were less active, but displayed spectacular thermal stability, while the clay/TiO2/MnAl-mixed oxide materials obtained with the aid of NaOH were least active. The observed patterns of catalytic activity bear a direct relation to the materials’ composition and their structural, textural, and redox properties. Full article
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