13460-50-9Relevant articles and documents
Tuning the structural stability of LiBH4 through boron-based compounds towards superior dehydrogenation
Cai, Weitong,Chen, Juner,Liu, Liying,Yang, Yuanzheng,Wang, Hui
, p. 1171 - 1180 (2018)
The remarkable destabilization effects of H3BO3, HBO2, and B2O3 on dehydrogenation of LiBH4 are revealed in this work. The effectiveness of destabilizing the structural stability is in the order of H3BO3 > HBO2 > B2O3. Besides, through optimizing the molar ratio of LiBH4 and H3BO3 and milling treatment, the destabilization effect, especially for dehydrogenation kinetics, is further enhanced. For example, at a temperature as low as 110 °C, 5.8 wt% hydrogen can be liberated in seconds from 2LiBH4-H3BO3 prepared through pre-milling. The investigation reveals that each of the LiBH4-H3BO3, LiBH4-HBO2 and LiBH4-B2O3 systems undergo multiple dehydrogenation stages corresponding to different destabilization mechanisms. The reaction at lower temperature is ascribed to the H+?H- coupling mechanism which should be enhanced by the [OH]-?[BH4]- interaction mode. Pre-milling treatment of LiBH4 and H3BO3 also promotes the H+?H- interaction which may have originated from the increasing contact area as a result of the fine particles, and therefore probably reduced the reaction activation energy. Consequently, it gives rise to the superior dehydrogenation performance of lower temperature, rapid kinetics, pure hydrogen and high capacity, which are required for off-board hydrogen energy vehicle application.
INFRARED AND RAMAN SPECTRA OF ORTHOROMBIC, MONOCLINIC AND CUBIC METABORIC ACID AND THEIR RELATION TO THE STRENGTH OF THE HYDROGEN BOND PRESENT
Bertoluzza, Alessandro,Monti, Patrizia,Battaglia, Maria Angela,Bonora, Sergio
, p. 123 - 136 (1980)
Infrared and Raman spectra of the three forms of metaboric acid (orthorombic, monoclinic and cubic) are presented and discussed.The behaviour of the asymmetric stretching vibration νOH and of the in-plane and out-of-plane deformations δOH and γOH shows that hydrogen bonds of different strengths are present in the three forms of metaboric acid, in accordance with X-ray diffraction measurements.This phenomenon is explained in a qualitative way by a valence bond treatment of the structural centres present in the three forms of metaboric acid.The remaining vibrational modes are related to the analogous modes present in borates and polyborates of known structure.
Tanaka, Haruhiko,Ohshima, Satoshi,Ichiba, Sumio,Negita, Hisao
, p. 37 - 42 (1981)
Influence of multiphonon and cross relaxations on 3P0 and 1D2 emission levels of Pr3+ doped borosilicate glasses for broad band signal amplification
Naresh,Ham, Byoung S.
, p. 321 - 330 (2016/01/20)
We discuss non-radiative relaxations of visible-near infrared (Vis-NIR) emissions originating from 3P0 and 1D2 levels of Pr3+ glasses. Thermal stability of host lithium aluminium borosilicate (LABS) glass is estimated from thermogravimetric and differential thermal analysis. The structural analysis of host LABS glass through Fourier transform infrared and Raman spectral profiles provide an insight to understand the effect of OH content and phonon energy on luminescence characteristics of Pr3+ ions. Visible emission spectrum of Pr3+ glass is composed of two prominent emission bands at 493 nm (3P0 → 3H4) and 605 nm (1D2 → 3H4) when excited by 448 nm. In NIR region a narrow emission band at 1.06 μm (1D2 → 3F3) and ultra-broad emission band at 1.49 μm (1D2 → 1G4) are observed for 488 nm excitation. For these emission transitions, emission decay curves are measured and analysed. The lifetime shortening due to non-radiative energy transfer is explained by multiphonon interactions and cross-relaxation routes, and later verified by Dexter's model. Electric dipole-dipole mechanism is identified to be responsible for ion-ion interactions intervening in 3P0 and 1D2 states of Pr3+ causing quenching in emission intensities and lifetimes. The large absorption and stimulated emission cross-sections of Pr3+ ions around 1.49 μm suggests suitability of a host material operating for broadband signal amplifications at low-loss optical telecommunication windows. Besides, emission parameters like stimulated emission cross-section (σemi), effective band width (Δλeff) are calculated for 1.49 μm (1D2 → 1G4) of Pr3+ doped silicate based glasses.
Synthesis of scandium orthoborate powders
Tkachenko,Fedorov,Kuznetsov,Voronov,Lavrishchev,Shukshin,Yarotskaya,Kononova
, p. 171 - 175 (2008/10/09)
Two polymorphs of scandium orthoborate, ScBO3, are synthesized by adding aqueous ammonia to aqueous solutions of scandium nitrate and boric acids and calcining the resulting precipitates. Dehydration of the precipitates reaches completion below
