Study of structural short order and surface changes of SiO₂ compounds

Abstract

Abstract. In this work dependence between structure, surface and reactivity of SiO 2 is investigated. Different samples are prepared with and without the presence of calcium cations and are characterized by different techniques. The FTIR frequency shifting of the bridging oxygen stretching vibration Si-O-Si and the binding energy shiftingof the Si2p and O1s photoelectron peaks have been observed and discussed. Results show the effect of presence of calcium on the structural change, surface and reactivity of SiO 2 aggregate. After reaction, a structural and SiO 2 surface changes occur, as the FTIR spectra illustrate depending on the presence of the calcium cations.

Bioglass‐based scaffolds coated with silver nanoparticles: Synthesis, processing and antimicrobial activity

“…Comparing both spectra, could be noticed that the band at 926 cm −1 , referent to silicon oxygen bending (Si–O), shifted to 911 cm −1 , and had the intensity increased after the Ag‐NPs incorporation. We attributed these changes to the formation of silanol groups (Si–OH, stretching vibration) on the glass ceramic surface (Aguilar‐Reyes, León‐Patiño, Villicaña‐Molina, Macías‐Andrés, & Lefebvre, 2017; Oufakir et al, 2018). It could also be noticed an additional band at 575 cm −1 in the spectrum of the scaffold coated with the Ag‐NPs correspondent to the bending mode of P–O, indicating the exposure of the phosphate groups of the glass–ceramic due the silicon degradation.…”