Hydrogen bonding interactions of H2O and SiOH on a boroaluminosilicate glass corroded in aqueous solution

Abstract

Hydrogen bonding interactions play an important role in many chemical and physical processes occurring in bulk liquids and at interfaces. In this study, hydrous species (H 2 O and Si-OH) on nano-porous alteration layers (gels) formed on a boroaluminosilicate glass called International Simple Glass corroded in aqueous solutions at pH 7 and pH 9, and initially saturated with soluble siliconcontaining species were analyzed using linear and non-linear vibrational spectroscopy in combination with molecular dynamics simulations. The simulation results revealed various possible types of hydrogen bonds among these hydrous species in nanoconfinement environments with their populations depending on pore-size distribution. The nano-porous gels formed on corroded glass surfaces enhance hydrogen bond strength between hydrous species as revealed by attenuated total reflectance infrared spectroscopy. Sum frequency generation spectroscopy showed some significant differences in hydrogen bonding interactions on alteration layers formed at pH 7 and pH 9. The glass dissolution under the leaching conditions used in this study has been known to be ten times faster at pH 7 in comparison to that at pH 9 due to unknown reasons. The simulation and experimental results obtained in this study indicate that the water mobility in the gel formed at pH 9 could be slower than that in the gel formed at pH 7, and as a result, the leaching rate at pH 9 is slower than that at pH 7.npj Materials Degradation (2020) 4:1 ; https://doi.

Remarkable damage in talc caused by electron beam irradiation with a dose of up to 1000 kGy: lattice shrinkage in the Z- and Y-axis and corresponding intrinsic microstructural transformation process speculation

“…According to the Sadtler Handbook of Infrared Spectra, 42,43 nitrite's (-O-N]O) characteristic stretching bands mainly appear near to 1650-1620 and 1320-1300 cm À1 , and nitrate's (O-NO 2 ) characteristic stretching bands mainly appear near to 1640-1610 and 1290-1280 cm À1 , and are very strong in intensity. Besides the NO x group, H 2 O normally exists in samples or KBr particles, which has two characteristic vibrations near to 3450 and 1635 cm À1 , 8,33,44,45 close to those observed in spectra. Thus, these two extra peaks might be assigned to H 2 O or the NO x group.…”

Chemical durability of borosilicate pharmaceutical glasses: Mixed alkaline earth effect with varying [MgO]/[CaO] ratio

“…A clean gold surface with mirror finish was utilized as a reference. Based on the complex refractive index for another borosilicate glass, international simple glass (ISG), 35 the characteristic penetration depth ( d p ) at which the IR intensity decreases to 36.8% is estimated to be ~600 nm in the Si–O–Si stretching region (1030–1100 cm −1 ). Thus, the effective probe depth can be assumed to be 3 × d p , which is ~1.8 μm.…”

A Study on the Interfacial Compatibility, Microstructure and Physico-Chemical Properties of Polyimide/Organically Modified Silica Nanocomposite Membrane

“…These images could also be supported by the 29 Si NMR data in Figure 3. Figure 3a for the pure silica sample is dominated by the Q 4 site which also indicates the presence of very less number of available hydroxyl groups that would undergo interaction with -COOH groups of PAA, whereas a higher number of hydroxyl groups in Figure 3b,c are available which can lead to the improved compatibilized composites with reduced particle sizes due to the strong hydrogen bonding interactions between -COOH groups of PAA and -OH groups of the GPMS-modified sample [27]. Also, the organic segment in GPMS can play a significant role in enhancing compatibility.…”

“…It is well-known that hydroxyl groups of silanol (Si-OH) undergo reactions with acid groups of polyamic acid (PAA) [16][17][18][19][20][21][22][23][24]27]. So far, most of the interactions have been interpreted from the final imidized composites only using FT-IR and improved thermomechanical properties.…”