Quanta 400 feg

Morphology of cryogel samples was evaluated using scanning electron microscopy (SEM, FEI Quanta 400FEG) under secondary electrons mode. Collagen/nanoHA scaffolds with and without OPS were attached with Araldite^TM to an aluminum sample holder. Samples were then sputter-coated with palladium-gold alloy (Bal–Tec—SCD 050). Image analysis through ImageJ software (Wayne Rasband) was used to determine the scaffolds porous size range. The pore diameter for each sample was determined as:
Where D and A were respectively, the pore diameter and the area of the circular projection of the pore in the image. The total number of pores analyzed for each material was over 200.
Mercury intrusion porosimetry method (Quantachrome Poremaster model No. 60) was used to evaluate total surface area, apparent density, and theoretical total porosity of all materials. The referred equipment allowed the detection of open pores in the range of 0.004–15.04 μm. Each scaffold was entered by mercury at high pressure, and data were obtained using Quantachrome Poremaster software.

The extinction and absorption spectra of solution samples were measured on a Hitachi U-3501 ultraviolet/visible/NIR spectrophotometer. The general images of the film morphology were obtained using an FEI Quanta 400 field emission scanning electron microscope (FESEM, FEI, Quanta 400 FEG) operated at 10 keV. X-ray diffraction measurements were performed with a Bruker D8 Advance Davinci powder X-ray diffractometer using a CuK_α source. TEM imaging was performed on an FEI Tecnai Spirit microscope operating at 120 kV.

X-ray diffraction (XRD) patterns were recorded on an X-ray diffractometer (Bruker, Bremen, Germany) with Cu-Kα radiation (λ = 1.5406 Å) over a 2θ angle range of 10–80°. X-ray photoelectron spectroscopy (XPS) were collected on a K-alpha X-ray photoelectron spectrometer (Thermo ESCALAB 250Xi, Carlsbad, CA, USA) with monochromatic Al Kα (hv = 1486.6 eV) from an X-ray source operating at 15 kV and 10 mA. All binding energies were referenced to the C 1s peak at 284.6 eV. The morphology of the photocatalysts were investigated via a scanning electron microscope (SEM, FEI Quanta 400 FEG), which was equipped with energy dispersive spectroscopy (EDS). High-resolution transmission electron microscopy (HRTEM) images were measured using a FEI Tecnai G2 F20 (HRTEM, FEI, Hillsboro, OR, USA), with an accelerating voltage of 200 kV. UV–visible diffuse reflectance spectra (UV–vis DRS) of the samples were measured on a UV–visible spectrophotometer (UV-2600, SHIMADZU, Kyoto, Japan) over the range of 200–800 nm using BaSO₄ as a reference. The binding energy was calibrated with reference to the C1 s peak at 284.8 eV.