Authors: WEIGUANG CHEN, UMIT BILGE DEMIRCI
Abstract: Thermogravimetric analysis (TGA) is a powerful technique for screening boranes envisaged for chemical hydrogen storage. The demonstration is based on the use of six metal (II) chlorides (MCl$_{2})$ (with M as 3d-metal or d$^{8}$-metal) as destabilizing agents of solid-state hydrazine borane (N$_{2}$H$_{4}$BH$_{3})$. On the basis of TGA profiles combined with derivative thermogravimetric (DTG) curves, it is shown that: e.g. (1) CuCl$_{2}$ is an inefficient dopant whereas it is efficient towards ammonia borane (NH$_{3}$BH$_{3})$; (2) one of the best destabilization results is achieved with N$_{2}$H$_{4}$BH$_{3}$ doped by 10 wt{\%} CuCl$_{2}$-NiCl$_{2}$, the sample decomposing from 30 $^{\circ}$C with greatly mitigated amounts of gaseous by-products; (3) in a few cases, the destabilization extent is so important that the doped samples could be envisaged as energetic materials. Above all, the present report shows the importance of TGA-DTG in the field of boron- and nitrogen-containing materials and the proposed protocol could be used by other groups so that literature-based comparisons are more relevant.
Keywords: Hydrazine borane, metal chloride, screening, thermogravimetric analysis, thermolysis
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