2.3.4. Infrared Spectroscopy (IR)

Samples were freeze-dried and pressed into a transparent pellet with KBr, Infrared spectra of particles and raw materials were collected in the range of 400–4000 cm−<sup>1</sup> on Nicolet™ iS™ 10 FT-IR Spectrometer (Thermo Fisher Scientific, Waltham, MA, USA) at a 4 cm−<sup>1</sup> resolution and 16 scans.
