Thermogravimetry (TG) is regarded as one of the most powerful techniques to investigate the fundamental characteristics of inorganic compounds. For a certain compound, information on the temperature-vs-mass relationship leads to a deep understanding of thermal behaviors as well as interactions with the surrounding atmosphere. Nevertheless, the interpretation would not be straightforward only with TG, when multiple gas species are involved in the thermal behaviors. Then, TG combined with a gas analyzer will effectively work. The combination of thermobalance and quadrupole mass spectrometer (Q-MS), the so-called “TG-MS,” is commercially available, but this technique has the following drawbacks relating to Q-MS: (i) poor quantitative accuracy in the gas amounts, (ii) the complexity caused by fragmentations of gas molecules in the ionization process, (iii) strict limitations of the measuring atmosphere due to the necessity of differential evacuation. For detailed studies on inorganic materials, an alternative analytical method that is capable of quantitative gas analyses under various atmospheres is highly desirable to compensate for the drawbacks of TG-MS.
The authors have recently designed and developed a novel system, “TG-GC,” which employs gas chromatography (GC) as a gas analyzer instead of Q-MS. As mentioned, TG-GC has several advantages, making this system a complementary tool to conventional TG-MS. In this article, we will show a basic concept and the capability of TG-GC. Then, some case studies with the use of TG-GC will be reviewed.