Speciation of hydrogen in silica glass by 1H MAS NMR

The H-bearing species in silica glass melted quartz powder in hydrogen atmosphere have been investigated using high-resolution 1H magicangle spinning nuclear magnetic resonance (1H MAS NMR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy and quadrupole mass spectrometry. The results show that molecular H2, hydroxyl (OH) groups and hydride (SiH) groups are present in the glass. The physically dissolved molecular H2 is represented by a broad NMR peak with the effects of strong H–H magnetic dipolar interactions. Isolated OH groups and hydrogen bonding OH groups in silica glass have been distinguished by the chemical shift of the 1H NMR spectrum. The influence of E’ center on the 1H MAS NMR spectrum are also analyzed.