D8 advance x ray

With the aim of observing the functional groups of PEO and fibroin incorporated in the matrices, the electrospun scaffolds were measured by attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy (VARIAN 640-IR, Varian Inc., Palo Alto, CA, USA). X-ray diffraction was performed using D8 Advance x-ray (Bruker, Billerica, MA, USA) diffractometer with a copper source (1.541 Å).

The crystalline structure of core/shell nanostructured Fe₃O₄/ZnO was characterized by X-ray diffraction (XRD) by using a Bruker D8 Advance X-ray diffractometer with Cu-Kα radiation (k = 1.5406 Å) at 2θ range of 10–70°. The X'pert Highscore Plus program was carried out to evaluate the grain size of the MNPs. The morphological characteristics, shape, and size of the MNPs and the core/shell nanostructure were observed through field emission scanning electron microscopy (FESEM; Hitachi S-4800) equipped with an energy dispersive X-ray spectrometer, and high-resolution transmission electron microscope (JEM 2100, JEOL). Fourier transform infrared (FTIR) spectroscopy (FTIR-GBC Cintra 40 Nicolet Nexus 670 FTIR), Raman spectra (XploRA, Horiba) and X-ray photoelectron spectroscopy measurement (Mutilab-2000 spectrometer with an Al Kα monochromatized source) were carried out to investigate the interaction between the Fe₃O₄ MNP core and ZnO shell. The optical properties of samples were characterized by UV-vis-NIR absorption spectroscopy (Hitachi U-4100) and HR photoluminescence system (IHR 500, Jobin Yvon) with an excitation wavelength of 350 nm. A commercial VSM (MicroSence EZ9) was used to observe the magnetic properties and saturation magnetization. Hysteresis loops were determined at an applied field of up to ±18 kOe at room temperature.

X-ray diffraction (XRD) was performed to obtain the crystal structure and phase purity of all the prepared samples using a Bruker D8 Advance X-ray diffractometer (Bruker, Karlsruhe, Germany) with a Cu-Ka radiation source (λ = 0.154056 nm). Transmission electron microscopy (TEM) and high-resolution TEM (HR-TEM) images were carried on a JEOL 2010F microscope (JEOL, Tokyo, Japan). The specific surface area and pore size distribution of the as-prepared samples were recorded with the measurement of nitrogen adsorption isotherm at 77 K using a Micromeritics ASAP 2020 analyzer (Micromeritics, Norcross, Georgia, USA). Electrical conductivity measurements were carried out on cylindrical pellets compressed from the powder samples at 30 MPa between two copper electrodes. The substrate area was restricted to 1 cm² while the thickness of the pellet was measured by a Vernier caliper. The value of resistivity was immediately measured by a JG-ST2258A resistivity tester (Jingge Electronic, Suzhou, Jiangsu, China) by inputting the thickness-area ratio as a parameter, followed by conversion to conductivity.

In situ high temperature X-ray powder diffraction studies were conducted using the Bruker D8 Advance X-ray diffractometer (40 KV, 40 mA) with Cu/Kα1 radiation (λ = 0.15406 nm). The patterns were recorded in an inert atmosphere in the 2θ range of 10 to 100° with a step size of 0.02° and a counting time of 0.33 s per step.
In situ high temperature Raman spectroscopic studies were carried out under a dry inert atmosphere using the LabRAM HR800 Raman spectrometer (Horiba Jobin Y’von, Paris, France) equipped with an ultraviolet pulse laser beam of 355 nm which was focused on the sample through a microprobe with a 4× objective lens. The average laser beam power on the sample was about 60 mW. It was equipped with a microscopic heating furnace (TS1500) (Linkam, Tadworth, UK) with a small temperature deviation of about ±1 K for investigating the microstructure of the sample at different temperatures. The platinum crucible which was applied to measure the high temperature experiment is protected by a patent [16 ]. A charge coupled device (CCD) detection system by an accumulated mode of 20 × 20 (20 times with 20 s each time) was used to collect Raman scattering light. The sample was held at the targeted temperature for 5 min before recording Raman spectra in order to ensure the sample reaches the targeted temperature and also avoids volatilization of the sample.

The XRD experiment was carried out by the D8 ADVANCE X-ray diffractometer manufactured by Bruker, Germany. Experimental conditions are tube pressure 40 kV, tube flow 200 μA, Cu target, diffraction width DS = SS = 1°, RS = 0.3 mm, scanning speed 2000 (d min⁻¹), scanning range 10°–80°.

The SEM images were performed using a field emission scanning electron microscope (SEM, Hitachi S4800, Chiyoda City, Japan) at an accelerating voltage of 15 kV. Photos were taken of different samples using a field emission transmission electron microscope (TEM, H-7650, Hitachi, Tokyo, Japan) at 150 kV. The structures were characterized by using a D8 Advance X-ray diffractometer equipped with Cu Kα radiation (XRD, λ = 0.154 nm, Bruker, Bremen, Germany). FTIR spectroscopy was performed by using an FTIR spectrometer (IR Tracer–100, Shimadzu, Nagoya, Japan) in the region of 4000~500 cm⁻¹. The Raman spectroscopy measurements were carried out using a Raman spectrometer (XploRA PLUS, Horiba, Japan) with a 514 nm laser. The nitrogen (N₂) adsorption–desorption isotherms of IGGO and the Fe₃O₄–urea–rGOAs were collected at 77 K on a Kubo × 1000 surface area and pore size analyzer (Beijing Builder, Beijing, China). The BET surface area (S_BET) was determined through the Brunauer–Emmett–Teller (BET) theory, and the pore volumes were processed through Barrett–Joyner–Halenda (BJH) models. The concentration of L2 in the gas stream was analyzed using a Fuli Analytical Instrument 9790 gas chromatograph equipped with a flame ionization detector (GC–FID, Chengde, China).