2.5. Characterization

TGA was carried out on the samples to evaluate their respective mass losses when subjected to successive heating. Thermogravimetric analysis was done using TGA Instrument Q500 V 6.7 (TA Instruments, New Castle, DE, USA) below flowing N₂/O₂ (60:40, v/v, mL/min). The heating was done from 25 to 800 °C at a heating rate of 10 °C/min.

The Fourier-transformed infrared spectra were acquired by the usage of a Thermo Nicolet 50 spectrophotometer equipped with a diamond Attenuated Total Reflection (ATR) crystal. The analysis was done from 500 to 4000 cm⁻¹ and the data was analyzed employing OMNIC 9.2.98 (Thermo Fisher Scientific, Gloucester, UK).

The FEI Nova NanoSem (Thermo Fisher Scientific, Gloucester, UK) scanning electron microscope was used to examine the morphology of the samples. Before the analysis, the samples were affixed with the aid of carbon tape onto a stainless steel stub and were sputter coated with a thin layer of Pt. The images were obtained using a probe at 3 mA and an accelerating voltage of 15 kV.

By using the aberration-corrected JEOL TEM (model JEM-1400, JEOL, Zurich, Switzerland) at 200 kV and analysis software ‘Gatan Digital Micrograph’, high-resolution high-angle annular darkish field TEM images were obtained for all the samples. The samples were drop cast on a 200-mesh carbon covered copper grid after they were dispersed in methanol and dried thereafter in ambient conditions.

The analysis was done using Zetasizer Ver. 7.10 (Malvern Panalytical Company, Malvern, UK), at a temperature of 25 °C, and 12 zeta runs were undertaken with the dispersant being distilled water. Data were analyzed using Zeta Potential Overlay Report ver. 2.1 (Malvern Panalytical Company, Malvern, UK).