Smartlab 3 kw

To investigate the phase composition of base and laser-modified materials, X-ray diffraction (XRD) technique was utilized. Both qualitative and quantitative analyses were performed. The whole powder pattern fitting method (WPPF) was used. The measurements were conducted with the diffractometer Smartlab 3 kW (Rigaku, Tokyo, Japan), equipped with Cu Kα (1.5406 Å) radiation source operated at 40 kV and 30 mA, on the as-lased surface without prior removal of surface roughness. A 2θ diffraction angle was 30–140°, and the scanning rate was 2°/min. The patterns used for the phase analysis were sourced from the International Centre for Diffraction Data database PDF-4 + 2021. The materials’ microstructures were analysed with the use of scanning electron microscopy (SEM) (Phenom ProX, Thermo Fisher Scientific, Waltham, MA, USA).

UV-Vis absorption spectrum was determined by a Shimadzu UV-2550 spectrophotometer. The fluorescence emission spectra were obtained using a Hitachi F-2700 spectrofluorophotometer. Fourier transform infrared (FT-IR) spectra were measured by Shimadzu Tracer-100 FT-IR Spectrometer. Morphological evaluation was carried out by scanning electron microscopy (ZEISS GeminiSEM 300). Energy dispersive X-ray spectroscopy (EDX) was carried out by Rigaku Smartlab 3 KW. Thermogravimetric analysis (TGA) was carried out by TA Q500. Fluorescence decay curves were obtained by Edinburgh FLS1000. Elemental compositions were detected by Thermo Scientific K-Alpha. BET surface area and the pore volume were obtained by Mike ASAP2460.

The absorption spectra of the samples were recorded using attenuated total reflection–Fourier transform infrared (FTIR) spectrometry (TENSOR II, Bruker, Karlsruhe, Germany) at a resolution of 4000–400 cm⁻¹ [31 (link)]. Scanning electron microscopy (SEM) (s-3400n, Hitachi, Tokyo, Japan) was used to study the morphology of the sample at 5 kV acceleration voltage. A polarizing microscope (BX41, Olympus, Tokyo, Japan) was used to observe the sample under cross-polarized light (200× magnification). The crystal structure of the sample was measured with an X-ray diffractometer (Smartlab 3KW, Rigaku, Tokyo, Japan) from 4° to 40° at a rate of 5°/min, with a step length of 0.02°. Thermogravimetric (TG) and derivative thermogravimetric (DTG) analyses were performed using a STA449-F5TAQ600 thermal analyzer (NETZSCH, Waldkraiburg, Germany) under a nitrogen flow of 20 mL/min. The sample (approximately 10 mg) was heated from 30 to 600 °C at a rate of 10 K/min. The adhesive properties of the modified starch samples were assessed using a Viscograph-E (Brabender, Duisburg, Germany) [32 (link)]. The particle size (zeta potential) of the sample was determined using a nano-zeta potential analyzer (Nano-ZS90, Malvern Panalytical, Malvern, UK). The measurements were performed using the samples prepared by dispersing starch nanocrystals in deionized water at 25 °C at a ratio of 0.01% w/v.