The thermal decomposition analysis was carried out using
DTA-TG apparatus (Shimadzu, model DTG – 60H). Nitrogen was
used as the carrier gas with a flow rate of 100 mL/min. The temperature
program used for the TGA was as follows: the samples were
heated from ambient temperature to a final temperature of
1000 C at a rate of 10 C/min. A sample mass of around 5 mg
was used for each test.