Advanced temperature-programmed desorption study on hydrogen evolution and thermal decomposition of KBH4 through comparison of powder bulk and thin film experiments

In this study, thermal decomposition behaviors of powder bulk and thin film KBH 4 samples are investigated by using a temperature-programmed desorption (TPD) method and compared through multi-mass analysis of desorbing chemical species and their fragments. It is then demonstrated that the TPD method is capable of providing some insight into not only the thermal decomposition and H 2 releasing mechanisms of KBH 4 , but also its chemical composition and quality. Specifically, as a result, there are found some byproducts of B 2 H 6 and/or possible polyboron hydrides (B n H 4 n – m ) in the thermal decomposition besides H 2 generation, depending on the chemical composition and quality of KBH 4 and the resultant decomposition temperature.