Spectroscopic Studies on Hydrazine-Boranes, Key Compounds for Chemical Hydrogen Storage

Hydrazine–boranes (H2NNH2·BH3 and H3B·NH2NH2·BH3) have been proposed for the storage of hydrogen, but these compounds have not created scope for extensive research works as ammonia– and methylamine–boranes have made these last decades. In the exciting research devoted to energy storage with environmentally friendly processes, hydrazine–borane, hydrazine–bisborane, and their simply substituted derivatives could provide a satisfactory response for hydrogen production and recyclability of the formed products. To date, knowledge of the physical and chemical properties of these compounds is still scarce. In this paper, the electronic structure of various hydrazine–boranes complexes is studied by ultraviolet-photoelectron spectroscopy (UV-PES), which is the experimental technique giving direct access to the energy of occupied molecular orbitals. Thus, UV-PE spectra were registered and first ionization energies were determined. Understanding of different types of interactions between nitrogen lone pairs and thei...