ChemInform Abstract: Formation of LiBH₄ Hydrate with Dihydrogen Bonding.

Abstract

LiBH4·H2O, obtained by exposing LiBH4 to air with about 5% relative humidity at room temperature is characterized by powder XRD, IR transmission spectroscopy, and DFT calculations.

Nanosheet-like Lithium Borohydride Hydrate with 10 wt % Hydrogen Release at 70 °C as a Chemical Hydrogen Storage Candidate

“…results show a reduction in the bond strengths between B and H1, H3, and H4 for LiBH 4 •H 2 O relative to pristine LiBH 4 . Moreover, the bonding character between H δ− of BH 4 and H δ+ of H 2 O was also observed because there is a distinct bonding peak at −7.7 eV for the H1−H5 bonding curve, implying the formation of dihydrogen bonding, which is in excellent agreement with a previous report 26. The local bonding of H δ− and H δ+ is very favorable for the release of hydrogen from LiBH 4 •H 2 O because of their strong affinity.…”

“…24 Meanwhile, the absorbances corresponding to the O− H stretching mode and the H−O−H bending mode of water were also discernible at 3423 and 1634 cm −1 , respectively. 26 Panels d and e of Figure 1 display scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images of the resultant product, respectively. Unique 2D leaf-like nanosheet morphology was observed for the prepared LiBH 4 •H 2 O from Figure 1d,e, and the thickness of the nanosheets was estimated to be 20−30 nm.…”

“…Here, it is worth highlighting that such nanosheet-like morphology has not been reported previously, where LiBH 4 • H 2 O was prepared by direct exposure to water vapor or air with about 5% relative humidity. 26,27 The prepared LiBH 4 •H 2 O nanosheets were subjected to thermal decomposition in isothermal and nonisothermal modes to evaluate their dehydrogenation performance. The mass spectroscopy (MS, Figure 2a) data as a function of temperature revealed that hydrogen was the sole gaseous product during the thermally activated decomposition of the prepared LiBH 4 •H 2 O nanosheets, and hydrogen desorption started at 50 °C, which falls in the required temperature range for practical applications proposed by the U.S. Department of Energy.…”

Microhydration of BH4–: Dihydrogen Bonds, Structure, Stability, and Raman Spectra

“…20 Dihydrogen bonding in NaBH 4 •2H 2 O was confirmed by Filinchuk et al 21 through single-crystal X-ray diffraction and vibrational spectroscopy. Yamawaki et al 22 studied the amount of moisture adsorbed by LiBH 4 under 5% relative humidity, identified LiBH 4 •H 2 O formation, and confirmed the existence of dihydrogen bonds in LiBH 4 •H 2 O via powder X-ray diffraction and Rietveld analysis. Researchers have long focused on dihydrogen bonds in solution, 2,23 but specific investigations on borohydride in aqueous solution are rare.…”

A Comparison of the End of the Canton and Nagasaki Trade Control Systems

“…In this system, only thirty Chinese ships were allotted credentials granting them permission to enter Nagasaki each year. 22 From 1717 to 1726, warships belonged to Northern Kyushu's domains destroyed Chinese ships engaged in smuggling in northern Kyushu by the order of the shogunate. 23 After this, it became difficult for foreign ships and merchants to smuggle into Japan other than through Nagasaki.…”