Amorphous films [BaTiO3 (BTO), SrTiO3 (STO), SrRuO3] on substrates and self-supported films (BTO and STO) were produced by controlling the film/substrate adhesion energy (level of clamping). The stress value in an as-deposited film depends on the clamping level, which defines the stress relief mode. In highly stressed films, the stress abatement is achieved via plastic transformation resulting in formation of “the strain-arranged structure of elastic domains.” Film fractures and delamination occur if the stress magnitude is too high and exceeds the elastic limit of the material. If the stress magnitude is low, the conditions favorable for nucleation and crystallization can arise. Stress in self-supported films is relieved mainly via shape change during film preparation, and the conditions favorable for nucleation and crystallization in annealed self-supported films arise more frequently.

Semiconductor quantum dots (QDs)-doped polystyrene (PS) microspheres with high luminescence were prepared using a self-assembly approach. Hydrophobic CdSe/ZnS QDs were first carboxylized by ligand exchange using mercaptocarboxylic acid. PS microspheres were separately encapsulated with polyethyleneimine via electrostatic interactions and then adsorbed with the carboxyl QDs to form QDs-doped microspheres. We then characterized the combinations using optical, electrical, and mechanical approaches and obtained the following findings: (i) microspheres can be fully coated by QD nanoparticles with a coverage rate of 1.0 pmole/cm2, in which QDs were evenly distributed on the surfaces; (ii) the anchored QDs exhibited similar optical property as they performed in isolated suspension; and (iii) the fluorescence of QDs-doped microspheres remained intact after stressed by ultrasound-induced cavitation, demonstrating the robustness of interactions between QDs and microspheres. The self-assembly approach developed in this study offered a facile and controllable strategy for preparation of QDs-encoded microparticles with high luminescence and stability.

The isocyanate-functionalized silica nanoparticles were chemically incorporated into the polyurethane (PU) during the synthesis of flexible PU foam from polypropylene glycol and toluene diisocyanate following the one-shot method with water as the blowing agent. Chemical incorporations of silica nanoparticles augmented hardness, initial modulus, and strength for tensile and compression loading. As results, shape fixity, shape recovery, and strain energy storage significantly increased with reduced hysteresis loss. It was found that the chemically incorporated silica particles effectively reinforce the PUs with improved dispersion and act as multifunctional cross-links, elastic energy storage, and relaxation retarder, which are beyond the conventional reinforcing filler. The maximum increases of dynamic properties and shape memory performances with 2% silica are an indication that the chemical incorporation is also limited by particle aggregations, though it appears at higher content than the simple blend.

Dielectric measurements (permittivity and hysteresis loop) of monocrystals of bis-thiourea pyridinium bromide inclusion compound have revealed for the first time ferroelectric properties of the studied samples. In the present article, a model of ferroelectric ordering on the basis of single-crystal x-ray diffraction data is described. In the low-temperature phase, the spontaneous polarization is directed along the a axis and ferroelectricity is of the mixed type (displacement and order-disorder component), whereas in the intermediate phase the spontaneous polarization is directed along the c axis and ferroelectricity is of the order-disorder type.

The unique set of mechanical properties found in rigid biological tissues, which combine high strength and stiffness with superior toughness, offer inspiration for the design of advanced functional structural materials with outstanding performance. This paper reports on the first utilization of one such biogenic material—siliceous sponge spicules, the skeletal elements of sponges (Poriphera)—as a unique naturally nanostructured template for vacuum deposition, while also reporting on the effects of the required chemical and thermal treatments for template preparation on the material’s microstructure and mechanical properties. The confined space within the central channel of spicules from the sponge Euplectella acts simultaneously as a nanotemplate and as a biogenic, optically transparent, glassy microchamber for the preparation of micrometer-sized clusters of fullerene-C60 through vacuum deposition onto the nanostructured surface. This biological material allows an unprecedented and unique microporous morphology of C60 particles to be obtained.

Molsidomine is one of the sydnonimine class of antianginal drugs that due to its structure exhibits both dipolar nature and aromatic properties. To select efficient carrier for the drug, unmodified and modified mesoporous silica materials were synthesized using phenyltriethoxysilane and 3-aminopropyltriethoxysilane via cocondensation and grafting routes. Synthesis of the mesoporous silica materials via cocondensation was carried out in the presence of D-glucose as pore-forming agent. Equilibrium isotherms for the adsorption of mesoionic compound molsidomine on the mesoporous silica materials were analyzed by the Langmuir, Freundlich, Redlich-Peterson and Langmuir–Freundlich (Sips) models. Langmuir model is found to be the best to explain the equilibrium data. Comparative study of the adsorption properties of the unmodified and modified mesoporous silica materials demonstrated that the phenyl-modified silica materials are the most efficient adsorbents for molsidomine. They exhibit the highest adsorption capacity and affinity in relation to the mesoionic compound.

In this research, we performed experimental investigations of the influence of copper presence on hardness of arsenic triselenide (As2Se3)–arsenic triiodide (AsI3) pseudobinary glasses. The samples belong to the group of chalcogenide glasses, that, when compared with oxide glasses, can be synthesized much more easily in a wide variety of compositions, allowing also fine-tuning of their properties. Here, presence of iodine (I) facilitates glass formation, whereas addition of copper (Cu) creates possibility for interesting optoelectronic properties. As it is important to study mechanical properties of materials with respect to their fabrication and manipulation, we report results of instrumented indentation testing (IIT) of bulk samples of Cux[(As2Se3)0.9(AsI3)0.1]100−x with x = 5, 10, 20, and 25 at.% of Cu. This technique enables fast determination of indentation hardness, hardness value according to Vickers and indentation modulus directly from the indentation load–displacement curves. It was shown that all these parameters increase linearly with the increase of copper content. Improvement of the mechanical properties justifies the addition of Cu into the glass matrix.

A new approach has been proposed to determine the interfacial toughness of soft-film hard-substrate systems based on wedge indentation experiments. In this approach, a comprehensive finite element study was undertaken to correct de Boer’s solutions, which were used to measure the wedge-indented interfacial toughness. Two-dimensional indentation simulations were first performed to systematically study the effects of the plastic properties of the films and the interfacial toughness itself on the correction factor for de Boer’s equations, which were used as closed-form solutions to evaluate the interfacial toughness. Further, three-dimensional simulations were used to investigate the effects of stress states on the interfacial toughness, which depends on the ratio of the indenter length to the film thickness. A universal correction expression for de Boer’s equations was obtained using a regression method. With this expression, a reverse algorithm was proposed to determine the interfacial toughness, and extensive numerical calculations were performed to verify that the present approach accurately evaluates the interfacial toughness. Finally, this new approach was applied to analyze the wedge indentation of low-k dielectric films, namely, methylsilsesquioxane and black diamond (BDTM) films, on a Si substrate.

Nickel nanoparticles (NNPs) synthesized by a modified polyol method using ethylene glycol as a reducing agent, palladium chloride as a nucleating agent, and polyvinylpyrrolidone (PVP) as a protective agent were investigated as a potential magnetic adsorbent for the purification of hexahistidine-tagged (His6-tagged) recombinant proteins. The synthesis resulted in nanoparticles having an average diameter of 68 ± 28 nm. The x-ray diffraction pattern confirmed the presence of nickel metal, as well as the presence of unreacted nickel (II) hydroxide Ni(OH)2. Magnetic characterization showed that a magnetization saturation of 39.3 electromagnetic unit (emu)/g at 20,000 Oersted (Oe) was reached rapidly and that the material exhibited ferromagnetic behavior. Protein purification results showed that the synthesized NNPs were highly selective for binding to a His6-tagged recombinant protein single-domain antibody ToxA5.1. In addition, NNPs were used for four adsorption cycles without significant binding capacity losses. These particles have shown great potential such as being easily synthesized, cost-effective, and highly selective magnetic adsorbents for the purification of His6-tagged recombinant proteins.

Gold nanoparticles (AuNPs) were biosynthesized using Bacillus megaterium, a common soil bacterium. Transmission electron microscopy images revealed that well-developed, spherical, homogeneous nanoparticles are formed extracellularly in reactions containing aqueous chloroaurate ions and conditioned medium at pH 4. Atomic force microscopy measurements showed that adhesion forces between biosynthesized AuNPs and breast cancer cells were almost six times greater than adhesion forces between biosynthesized AuNPs and normal breast cells. Furthermore, adhesion forces of biosynthesized AuNPs to breast cancer cells were three times greater than adhesion forces between chemically synthesized AuNPs and the same breast cancer cells. Finally, adhesion forces between biosynthesized AuNPs conjugated to breast-specific antibodies (AuNP-Ab conjugates), and breast cancer cells were almost five times greater than adhesion forces between unconjugated AuNPs and breast cancer cells. The implications of the results are discussed for the development of nanostructures for the targeted detection and treatment of breast cancer.

Deposition of ibuprofen (IBU) into ordered mesoporous silica SBA-15 was carried out to prepare controlled release nanodrug using supercritical carbon dioxide (scCO2) as solvent at 17 MPa and 310.15 K. The maximum drug loading of IBU/SBA-15 was as high as 41.96%. The characterization of the obtained materials was performed using x-ray diffractometry (XRD), scanning electron microscopy (SEM), and nitrogen (N2) adsorption-desorption isotherms; the results indicate that most adsorbed drugs were inside the nanoscale channels. The in vitro study shows that the time of complete (100%) release significantly decreases as drug-loading decreases. The interesting aspect is that the samples with similar drug loading display different release rates, which may be due to differences in the drug quantity adsorbed inside the pores. In addition, the modified Noyes-Whitney equation was used to model the release kinetics for all the samples and a good agreement was obtained between the model representation and experimental data. In addition, the solubility of IBU in scCO2was tested through a high-pressure view cell at the temperature range of 298.15–320.15 K and pressure range of 7–17 MPa. The experimental solubility data were well correlated using Chrastil’s equation as well as Mendez-Santiago and Teja’s equation.

Two-dimensional (2D) disordered copper 1,3,5-tricarboxylate film on copper foil was first reported in this paper. In the x-ray powder diffraction pattern of the as-prepared film, there were only two diffraction peaks exist in d value of 6.60 and 3.32 Å, which were correspond to the (400) and (800) diffractions of bulk HKUST-1, respectively. And the d value of 6.60 Å in bulk HKUST-1 is very close to the thickness of one-layered Cu2+ plus one-layered C9H3O63− (6.59 Å). The structure of as-prepared film was proved to be 2D disordered copper 1,3,5-tricarboxylate film. The periodical stacking of Cu2+ and C9H3O63−is perpendicular to the substrate. There is no periodic structure within the layer. Scanning electron microscopy, transmission electron microscope (TEM), high-resolution transmission electron microscope, infrared, Raman, and x-ray photoelectron spectrometer supported this result. This kind of disorder probably also existed in the reported HKUST-1 film that shows strong (400) diffraction in x-ray diffraction (XRD) pattern. This result probably explains why (400) diffraction in XRD pattern of reported synthesized HKUST-1 film is anomalously strong. This strategy is simple. No seed, no pretreated solvothermal mother liquors, and no specific functionalization are required.

Uniform PbS nanostructures with varied morphology have been synthesized by a surfactant-assisted reflux route. ZnS and CdS layers were successfully coated onto PbS nanocrystals by encapsulation or epitaxial growth. The nanocrystals were characterized by x-ray diffraction, (high-resolution) transmission electron microscopy, selected area electron diffraction, and scanning electron microscopy. The truncated cubic nanostructures displayed a symmetric emission band at about 860 nm. Diffuse reflectance infrared (IR) spectroscopy was measured to estimate the band gap. High temperature and high frequency measurements of impedance and permittivity taught that the samples were stable and showed collateral evidence of the existence of epitaxial layers. Measurements illustrate that the luminescent properties of semiconductor PbS nanostructures are closely related to their surface nature, and encapsulation can affect their electrical properties and photoluminescence performance greatly. The study may prove useful in developing high frequency IR sensors and light signal amplification devices.

KLa2Ti3O9.5 and KLa2Ti3O9.5:Er3+ nanocrystals were successfully synthesized using a hydrothermal method and a subsequent calcination treatment. The band gap (Eg) of the KLa2Ti3O9.5 nanocrystals was calculated to be about 2.56 eV by means of the reflectance diffusion technique. Under 980-nm excitation, the KLa2Ti3O9.5:Er3+ nanocrystals emitted intense green (2H11/2/4S3/2 → 4I15/2) and red (4F9/2 → 4I15/2) upconversion (UC) luminescence. In comparison with pure KLa2Ti3O9.5, the KLa2Ti3O9.5:Er3+ nanocrystals exhibited a higher activity for water splitting into H2 under simulated solar light irradiation. We suggest that the enhancement of photocatalytic activity is related to the Brunauer-Emmett-Teller (BET) surface area and UC luminescence of KLa2Ti3O9.5:Er3+.

Thermoelectric (TE) devices, both TE generators (TEGs) and TE coolers (TECs), have short service lives as TE materials undergo degradation from sublimation, oxidation and reactions in corrosive environments at high temperatures. We have investigated four high-temperature polymers (HTPs) as candidates for TE element coatings and/or TE device fillers to minimize or prevent this degradation. Two of these HTPs have shown good thermal stability in the 400–500 °C temperature range. The coatings were initially applied to bismuth telluride (Bi2Te3)-based TE materials that are used for commercial power generation devices specified for operation up to 250 °C. The HTPs protect the Bi2Te3 from both weight loss and weight gain up to 500 °C. This is clearly outside the optimum TE operation range of Bi2Te3 materials, but demonstrates the ability of the HTP coatings to protect the Bi2Te3 materials at least up to 250 °C. The properties that HTP materials demonstrated during the examination of suitability of their use for TE element coatings and/or TE device fillers using Bi2Te3are expected to hold good for higher operating temperature TE materials also.