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The strontium (Sr) substitution plays critical roles in physical-chemical-biological properties of hydroxyapatite (HA) bioceramics due to the structural distortion induced by doping. Herein, the effects of Sr substitution on the structural distortion of HA were investigated systematically by Rietveld refinement and Raman spectroscopy. We compared the occupation possibility of Sr in the lattice and pointed out its preferred occupancy. The effects of doping on lattice parameters, bond length, bond angle and crystallite size were also studied. The evidence, that doping will give rise to the distorted structure, has been shown. In addition, the PO43−, Ca-PO4 and OH− vibrations were further studied to verify the structural evolution and distortion. This work may be helpful in further studying on the structure-property relationship of Sr substitution HA.

van der Waals materials have attracted much scientific and technological interest recently. In this study, We synthetized a novel van der Waals brown semitransparent semiconductor: InTeI single crystal, and characterized its structure and optical properties carefully. Single crystal diffraction results show a layered structure with the P21/c space group and 4.09 A interlayer distance at room temperature. UV–visible absorption and photoluminescence spectra reveal that the band gap of InTeI is ~2.219 eV. The photocurrents under an illumination wavelength of 500 nm and non-illuminated conditions indicate its potential applicability in the photovoltaic field. Our work may be benefit for the understanding of its practical applications in field emission devices and photodectors.

The effects of Mn-doping on the structural evolution of β-Tricalcium Phosphate were studied using X-ray powder diffraction with Rietveld refinement and Raman spectroscopy. The lattice parameters and unite cell volumes decrease with the increase of Mn-doping without changing their R3c space group. Ca(5) and Ca(4) sites could be substituted by Mn2+. The manganese substitution resulted in the structural instability and distortion, which also could generate the shift of Raman peaks. The broad band assigned to Ca–PO43− was changed from 272 cm−1 to 292 cm−1, which may indicate the decreasing of bond lengths between Ca(Mn) and PO43−. This work may benefit for the further study of the structure–property relationship of β-Tricalcium Phosphate.

We investigated the effects of structural evolution on the enhanced Hydrogen Evolution Reaction (HER) for Pd nanoparticles (NPs) @ 2H-MoS2 studying by a modified in-Situ electrochemical Raman spectroscopy. This novel technique dramatically reduces the influence of air bubbles on the electrode surface for Raman signal detecting. The in-Situ Raman results reveal that the terminal S-S is the true HER active sites. Pd NPs can promote the appearance of terminal S-S bonds earlier, make some bands shifting dramatically, make or break some chemical bonds of MoS2, which may relate to the enhanced HER.

Hydroxyapatite (HAP) is a promising biomaterial with various applications in the biomedical fields. Herein, nanorod-assembled porous microspheres of HAP/casein have been prepared using adenosine 5′-triphosphate disodium salt (Na2ATP) as a phosphorus source, calcium chloride as a calcium source in the presence of casein sodium salt as a template by the hydrothermal method. This method is simple, surfactant-free and environment-friendly. The effect of hydrothermal time on the morphology and crystal phase of the product was investigated. The as-prepared products were characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TG). The as-prepared HAP/casein nanorod-assembled porous microspheres have promising applications in the biomedical fields.

The structural, magnetic, and dielectric properties of Bi 1− x Ba x Fe 1− x Ti x O 3 ( x ≤0.25) ceramics are studied systematically. The symmetry of the unit cell for BiFeO 3 co-doping with Ba and Ti remains the space group of R3c . The addition of Ba and Ti increases the unit cell volume without changing the unit cell symmetry. The remnant magnetization decreases monotonically with increasing the doping content, which may originate from contraction in Fe–O–Fe bond and FeO 6 octahedron. Charge compensation occurs in BiFeO 3 with Ba and Ti co-doping, which may suppress the charge defects and decrease the magnetism. The substitution of Fe with smaller radial Ti ion supplies larger vibration space in FeO 6 octahedron, which may enhance the dielectric constant and decrease the dielectric loss significantly.

Magnesium phosphate is an alternative to well-known calcium phosphate biomaterials and an excellent candidate for biomedical applications due to its outstanding biocompatibility and biodegradability. However, to the best of our knowledge, the microwave-assisted hydrothermal rapid synthesis of magnesium phosphate hierarchical structures (MPHS) has not been reported. Herein, we report the microwave-assisted hydrothermal method for the rapid synthesis of MPHS using MgCl 2 ·6H 2 O and adenosine 5 ׳ -triphosphate disodium salt hydrate (Na 2 ATP) in aqueous solution in the absence of any surfactant. The effects of the microwave heating temperature and Na 2 ATP on the morphology of the products are investigated. This method is facile, rapid, surfactant-free and environmentally friendly. The as-synthesized products are characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric (TG) analysis.

At temperature range of 25–800 °C, in situ X-ray diffraction studies on Bi 0.8− x Pr x Ba 0.2 FeO 3 ( x ≤ 0.1) ceramics are performed. The unit cell symmetry remains unchanged, while temperature dependence of lattice parameters and unit-cell volumes vary. There are no phase decomposition and structural phase transition detected in the system, which indicate that Pr, Ba co-doping may stabilize the structure of BiFeO 3 ceramic. The unit cell thermal expansion and thermal expansion coefficients are positive. However, for sample with x = 0.1, i . e ., Bi 0.7 Pr 0.1 Ba 0.2 FeO 3 , the unit cell structural stability decreases, and the thermal expansion coefficient increases. The thermal expansion coefficients abnormal around the Neel temperature are observed, which may suggest a possible antiferromagnetic–paramagnetic transition. It is probably the explanation for their low thermal expansion coefficient during the heating process.

Calcium phosphates are important biomaterials for biomedical applications. Herein, we report microwave-assisted hydrothermal rapid synthesis of amorphous calcium phosphate (ACP) nanoparticles and hydroxyapatite (HAP) microspheres using cytidine 5′-triphosphate disodium salt as a phosphate source. This synthesis method does not need any surfactant and is very rapid (1 min at 150 °C). The pH value has a significant effect on the morphology and crystallinity of the product. Aggregated ACP nanoparticles, hierarchically nanostructured solid HAP microspheres and hollow HAP microspheres are obtained at pH 7.0, 5.0 and 4.3, respectively. The as-prepared products are characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric (TG) analysis.

The phase transformation for the growth processing of BiFeO 3 ceramics are in-situ studied using high temperature X-ray diffraction. The reaction equation and thermodynamic stability behavior in the sintering process are also discussed. Results show that Fe 2 O 3 does not react with Bi 2 O 3 until the phase transforms from the monoclinic into the cubic. Impurity phases Bi 25 FeO 39 and Bi 2 Fe 4 O 9 are the transient phases in the reaction sintering process. Meanwhile sintering temperature is inversely proportional to the heating rate, which may relate to the procedure of phase nucleation, decomposition and transformation.

Nanocomposites with magnetic iron oxide as the hollow core, silica as the middle shell and calcium silicate as the outer shell are the ideal agent for application in medical diagnosis and therapy. In this paper, by sol–gel coating the self-assembled nanoparticles of magnetic iron oxide with silica, then reacting with Ca(NO 3 ) 2 ·4H 2 O at 600 °C in inert N 2 atmosphere, the nanocomposite consisting of hollow-core-double-shell magnetic iron oxide/silica/calcium silicate has been successfully synthesized. The components of the hollow core, middle layer and outer layer are Fe 3 O 4 , SiO 2 , CaSiO 4 , respectively. The nanocomposite has a superparamagnetic behavior and good drug delivery performance, which are promising for the application in targeted drug delivery.

The temperature dependence of the crystal structure for Bi 1−2.5 x Pr 1.5 x Ba x FeO 3 ( x = 0.05, 0.1) polycrystallines is studied by X-ray powder diffraction with Rietveld refinements in the temperature range of 25–800 °C. A structural phase transition of Rhombohedral-to-Cubic occurs for Bi 0.875 Pr 0.075 Ba 0.05 FeO 3 sample in the temperature of 600–700 °C, which may relate to its unstable rhombohedra distorted structure with the space group R3c . The rarely decomposition of these samples indicates that the Pr, Ba co-doped make the BiFeO 3 ceramics more stable. The thermal expansion determined by the temperature dependence of the unit-cell lattice parameters and volumes for Bi 1−2.5 x Pr 1.5 x Ba x FeO 3 samples is also investigated, which shows an isotropic and positive behavior. The average thermal expansion coefficient decreases with the increasing x . We argue that the Cubic crystal structure with the high symmetrical of the space group Pm3m may be more stable for Bi 0.75 Pr 0.15 Ba 0.1 FeO 3 sample, which may explain the reason why no phase transition occurs and its lower thermal expansion efficiencies. An obvious change in the slope of the linear fitted lines between 300 °C and 400 °C suggests a possible antiferromagnetic–paramagnetic transition, which occurs around the Neel temperature of the Bi 1−2.5 x Pr 1.5 x Ba x FeO 3 samples.

The design and synthesis of calcium phosphates (CPs) nanostructures with high specific surface areas are significant for drug delivery systems. Herein, we report a simple surfactant-free sonochemical synthesis of carbonate apatite (CAP) nanorod bundles with a high specific surface area (183.39 m 2 g −1 ) using an aqueous solution of CaCl 2 ·2H 2 O and (NH 4 ) 2 HPO 4 . The effects of experimental parameters including reactant species, pH value, calcium ion concentration, reaction time on the specific surface area of the product were investigated. The products were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The as-prepared CAP nanorod bundles were explored as the drug nanocarrier, which exhibited a sustained drug release behavior in simulated body fluid.

Sodium polyacrylate modified Fe 3 O 4 magnetic microspheres (SPMFMs) formed by self-assembly of nanocrystals were synthesized by a solvothermal method in mixed solvents of ethylene glycol and water. The SPMFMs exhibited a quasi-superparamagnetic behavior, and the saturation magnetization reached as high as 81.6 emu/g. The potential applications of the SPMFMs in the magnetic resonance imaging (MRI), drug delivery and waste water treatment were investigated. The loading capacity of the SPMFMs for bovine hemoglobin was 95 mg/g, and 33% of the loaded bovine hemoglobin was released in a period of 75 h. The adsorption for methylene blue and fuchsin basic using the SPMFMs as the adsorbent in the waste water treatment was efficient and rapid (within 1 min). The SPMFMs after the adsorption of the organic pollutants could be recycled and reused effectively with a slightly reduced adsorption capacity.

Sb2Te3 nanobelts and nanosheets were synthesized by a hydrothermal method using SbCl3 and TeO2 as the antimony and tellurium source, hydrazine hydrate as a reducing reagent, polyvinyl alcohol as a surfactant and water as the solvent. The effects of experimental parameters on the product were investigated. The experiments indicated that the elemental Te formed during the reaction, acting as a reactive and self-sacrificial template for the formation of Sb2Te3 nanobelts. The morphology evolution from Sb2Te3 nanobelts to nanosheets with the prolonging hydrothermal time was observed. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), selected area electron diffraction (SAED), Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). The thermoelectric properties of the tablet samples of Sb2Te3 nanostructured powders with different morphologies prepared by a room-temperature pressurized method were investigated.

A commonly used method for the synthesis of one-dimensional (1-D) nanostructures of metal tellurides is to employ 1-D nanostructured elemental tellurium as a reactive and self-sacrificial (RSS) template which can participate in the reaction, convert into the designed products and disappear eventually without the additional steps to remove the template. Herein, we report a rapid microwave-assisted solvothermal method by employing Te nanotubes as the RSS template to prepare Cu(2 − X)Te single-crystalline nanowires with diameters of 100–200 nm and lengths of several micrometers. The products are characterized by XRD, SEM, TEM, EDS, SAED and FTIR. The electrical conductivity of the Cu(2 − X)Te nanowire tablet sample prepared by a room-temperature pressurized method is also investigated.