Nicolet is50 spectrophotometer

The complex thermal analysis of the precursor dried gel was recorded using a Shimadzu DTG-60 equipment (Shimadzu Corporation, Kyoto, Japan), in air, up to the temperature of 650 °C, with a heating rate of 10 °C/min. The morphology achieved in all stages was studied by scanning electron microscopy (SEM) with an FEI Quanta Inspect F microscope (FEI Company, Hillsboro, OR, USA) equipped with an energy-dispersive X-ray spectroscopy (EDX) probe. A Thermo Scientific Nicolet iS50 spectrophotometer (Thermo Fisher Scientific, Waltham, MA, USA) was used for studying the chemical bonding and grouping within materials through Fourier-transform infrared spectroscopy (FTIR), the wavenumber ranging between 400 and 4000 cm⁻¹, with 4 cm⁻¹ resolution. A Shimadzu XRD 6000 diffractometer (Shimadzu Corporation, Kyoto, Japan) was employed for analyzing the phase composition of the intermediate powder and final target through X-ray diffraction (XRD), while a PANalytical Empyrean diffractometer (Malvern Panalytical, Royston, UK) was operated at grazing incidence in the case of the coated samples, both with Ni-filtered Cu, Kα radiation (λ = 1.54 Å), 2θ ranging between 10 and 80°, with a scan speed of 2°/min.

The FT-IR spectroscopy spectra of the HE extracts were acquired using a Thermo Fisher Scientific (Waltham, MA, USA) Nicolet iS50 spectrophotometer. The analysis encompassed a range of 400 to 4000 cm⁻¹, with a resolution of 4 cm⁻¹. To ensure uniformity and reliability, the sample underwent a preparation step where it was mixed with 400 mg of KBr and then subsequently subjected to grinding and tableting processes.

The surface morphology of the samples was investigated by immersing them in the aggressive solution for 24 h without/with 0.4 g L⁻¹ GG.
FTIR analysis was carried out using a Thermo Scientific (Indianapolis, IN, USA) Nicolet iS50 spectrophotometer equipped with an attenuated total reflectance (ATR) accessory (Indianapolis, IN, USA). The FTIR spectra were obtained at a spectral resolution of 4 cm⁻¹ with 256 co-added scans over the range from 3600 cm⁻¹ to 800 cm⁻¹. SEM-EDS analysis was carried out by using a JEOL scanning electron microscope at 2000× magnification. Atomic force microscopy (AFM) topography images were obtained using a NanoIR2 Anasys device (Santa Barbara, CA, USA). AFM images were performed in tapping mode using a 75 kHz resonance frequency (cantilever with a spring constant of 3 N m⁻¹), scan rate 0.5 Hz, and resolution of 300 pts in the x and y directions. The average roughness (R_a) and the root-means-square (R_q) were determined on the surface area of 10 × 10 μm².

The samples and KBr were mixed in a mortar with a mass ratio of about 1:100. Then, the Col. V sample and Col. I were pressed into a uniform transparent sheet with a hydraulic instrument. The light transmittance of the biofilm and the Col. I were measured at a wavelength of 400-4000 cm⁻¹ with a NICOLET iS 50 spectrophotometer (Thermo, USA), with a scanning resolution and a scanning time of 4 cm⁻¹ and 100 s, respectively.