The vibrational spectra of orthoboric acid and its thermal decomposition products

Broadhead, Peter; Newman, G.A.

doi:10.1016/0022-2860(71)87074-6

Cited by 40 publications

(15 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Four main characteristic IR peaks are found in these samples: 3200e3400 cm À1 for OeH stretch, 1460 cm À1 and 1200 cm À1 for BeO stretch, and 780 cm À1 for BeO bend, which are consistent with FT-IR characteristics of boric acid and metaboric acid (Fig. 5) [35]. Moreover, in the cases of H 2 O/AB ¼ 1.28 and 2.57, there exist other IR characteristic peaks: 2335 cm À1 for BeH stretch, 1620 cm À1 for NeH bend, as well as 1053 cm À1 and 1160 cm À1 for BeH torsion (Fig.…”

Section: Analysis Of the Hydrolysatesupporting

confidence: 81%

“…In addition, mixture of boric acid and metaboric acid are the dominant boron oxide products. However, if emitted heat of reaction could be well managed not to evaporate water but to decompose the boric acid and metaboric acid to form born trioxide (B 2 O 3 ) [34,35], it is possible to achieve a 100% conversion predicted as Eq. (4).…”

Section: Analysis Of the Hydrolysatementioning

confidence: 99%

See 1 more Smart Citation

Hydrogen production from hydrolysis of ammonia borane with limited water supply

Chou

Lee

Chen

2012

International Journal of Hydrogen Energy

View full text Add to dashboard Cite

Section: Analysis Of the Hydrolysatesupporting

confidence: 81%

Section: Analysis Of the Hydrolysatementioning

confidence: 99%

Hydrogen production from hydrolysis of ammonia borane with limited water supply

Chou

Lee

Chen

2012

International Journal of Hydrogen Energy

View full text Add to dashboard Cite

“…This argument does not apply to v-B 2 O 3 :OH, for which there is no evidence for interstitial water molecules. 32,44,45 In this glass, the hydrolysis of BO-B bonds is rapid even under normal conditions. Furthermore, we find it unlikely that hydronium ions constitute the prevalent form of the protonrelated electron-trapping center in low-OH silica.…”

Section: E Interstitial Hydronium Ionsmentioning

confidence: 93%

“…This shift increases from 100 cm Ϫ1 in the ␣-HBO 2 to 200-380 cm Ϫ1 in the v-B 2 O 3 :OH glass. 32,44,45 This suggests progressive weakening of hydrogen bonds. The broadening of the OH band in ''wet'' glasses indicates a distribution of the OH-O bond lengths and strengths.…”

Section: A the Structure Of V-b 2 O 3 :Ohmentioning

confidence: 99%

Electron trapping and hydrogen atoms in oxide glasses

Shkrob

Tadjikov

Chemerisov

et al. 1999

The Journal of Chemical Physics

View full text Add to dashboard Cite

Absence of recombination of neighboring H atoms in highly purified solid parahydrogen: Electron spin resonance, electron-nuclear double resonance, and electron spin echo studies Transient nucleation in oxide glasses: The effect of interface dynamics and subcritical cluster population Trapped hydrogen atoms generated in 3 MeV ␤-radiolysis of B 2 O 3 :OH glass below 140 K were studied using electron paramagnetic resonance ͑EPR͒. Two types of trapped H atoms were present in this glass; one was an interstitial atom located in a void between several BOB fragments, another was the atom trapped in a cage between two B 3 O 6 ͑boroxol͒ rings connected by hydrogen bonds. The geometry of the trapping site was determined using electron spin echo envelope modulation ͑ESEEM͒ spectroscopy. Time-resolved pulsed EPR was used to observe mobile H atoms at 300-500 K. The lifetimes ͑10-100 s͒ of the H atoms were controlled by ϳ10 18 cm Ϫ3 of metastable spin centers. The H atoms migrated with diffusion constant of 1.5ϫ10 7 cm 2 /s ͑activation energy of 0.13-0.16 eV͒, mean residence time at the site of 4-5 ns, and mean jump length of 0.56 nm ͑at 300 K͒. This site-to-site migration causes rapid spin relaxation due to modulation of magnetic interactions, such as dipole-dipole interaction of the unpaired electron of the H atom with 10 B and 11 B nuclei. Though there was no observed H/D kinetic isotope effect on the decay/diffusion of the hydrogen atoms, there was a significant isotope effect on their radiolytic yield (␣Ϸ1.5-1.6). This effect is comparable to the one observed in SiO 2 :OH and aqueous acid glasses. This similarity suggests that in the room-temperature ''wet'' SiO 2 and B 2 O 3 glasses, mobile H atoms are generated via electron trapping at the proton͑s͒ associated with threefold coordinated oxygen ͑-OH 2 ϩ and/or ϾOH ϩ centers͒. Semiempirical MNDO simulations were used to estimate energetics of such electron trapping reactions. ͓S0021-9606͑99͒52335-0͔

show abstract

“…The initial dry sample spectrum shows a broad shoulder peak at 1260 cm -1 . This peak might be due to a small amount of boron oxide (B 2 O 3 ) formed locally upon extreme drying [28,42]. However, this peak disappears immediately as soon as the coating is exposed to humid environment, indicating its transformation into boric acid [42][43][44].…”

Section: Spectroscopic Investigation Of the Adsorbed Molecules On Bormentioning

confidence: 94%

Origin of Ultra-Low Friction of Boric Acid: Role of Vapor Adsorption

2015

View full text Add to dashboard Cite

Boric acid is a lamellar solid lubricant that can give an ultra-low friction coefficient. The origin of this ultra-low friction of boric acid was investigated using tribology and spectroscopy techniques in inert, humid, and organic vapor conditions. It was found that boric acid itself experiences high friction and catastrophic surface wear when rubbed with a stainless steel ball in dry nitrogen or oxygen environments, but it gives very low friction (l = 0.06) in humid and acetone vapor environments. Short-chain alcohol vapors (ethanol and n-pentanol) did not show these ultra-low friction values. Vibrational spectroscopy indicates that the lubricating vapors do not adsorb on the basal plane of the boric acid crystal but likely adsorb onto the edge sites of the lamella. The alcohol molecules impinging from the gas phase readily react with the boric acid to form a high vapor pressure molecule that desorbs from the surface. The ''unlocking'' of the highenergy edge sites by adsorbed acetone and water vapor appears to be needed for the lamella to shear along the basal plane direction.

show abstract

The vibrational spectra of orthoboric acid and its thermal decomposition products

Cited by 40 publications

References 17 publications

Hydrogen production from hydrolysis of ammonia borane with limited water supply

Hydrogen production from hydrolysis of ammonia borane with limited water supply

Electron trapping and hydrogen atoms in oxide glasses

Origin of Ultra-Low Friction of Boric Acid: Role of Vapor Adsorption

Contact Info

Product

Resources

About