Skip to main content

Research Repository

See what's under the surface

Advanced Search

Degradation and Characterization of Resorbable Phosphate-Based Glass Thin-Film Coatings Applied by Radio-Frequency Magnetron Sputtering

Stuart, Bryan; Stuart, Bryan W.; Gimeno-Fabra, Miquel; Segal, Joel; Ahmed, Ifty; Grant, David M.

Authors

Bryan Stuart

Bryan W. Stuart

Miquel Gimeno-Fabra

Joel Segal

Ifty Ahmed

David M. Grant



Abstract

Quinternary phosphate-based glasses of up to 2.67 μm, deposited by radio-frequency magnetron sputtering, were degraded in distilled water and phosphate-buffered saline (PBS) to investigate their degradation characteristics. Magnetron- sputtered coatings have been structurally compared to their compositionally equivalent melt-quenched bulk glass counterparts. The coatings were found to have structurally variable surfaces to melt-quenched glass such that the respective bridging oxygen to nonbridging oxygen bonds were 34.2% to 65.8% versus 20.5% to 79.5%, forming metaphosphate (PO3)−(Q2) versus less soluble (P2O7)4− (Q1) and (PO4)3− (Q0), respectively. This factor led to highly soluble coatings, exhibiting a t1/2 degradation dependence in the first 2 h in distilled water, followed by a more characteristic linear profile because the subsequent layers were less soluble. Degradation was observed to preferentially occur, forming voids characteristic of pitting corrosion, which was confirmed by the use of a focused ion beam. Coating degradation in PBS precipitated a (PO3)−metaphosphate, an X-ray amorphous layer, which remained adherent to the substrate and seemingly formed a protective diffusion barrier, which inhibited further coating degradation. The implications are that while compositionally similar, sputter-deposited coatings and melt-quenched glasses are structurally dissimilar, most notably, with regard to the surface layer. This factor has been attributed to surface etching of the as-deposited coating layer during deposition and variation in the thermal history between the processes of magnetron sputtering and melt quenching.

Journal Article Type Article
Publication Date Dec 16, 2015
Journal ACS Applied Materials & Interfaces
Print ISSN 1944-8244
Electronic ISSN 1944-8252
Publisher American Chemical Society
Peer Reviewed Peer Reviewed
Volume 7
Issue 49
Pages 27362-27372
APA6 Citation Stuart, B. W., Stuart, B., Gimeno-Fabra, M., Segal, J., Ahmed, I., & Grant, D. M. (2015). Degradation and Characterization of Resorbable Phosphate-Based Glass Thin-Film Coatings Applied by Radio-Frequency Magnetron Sputtering. ACS Applied Materials and Interfaces, 7(49), 27362-27372. https://doi.org/10.1021/acsami.5b08957
DOI https://doi.org/10.1021/acsami.5b08957
Keywords Phosphate glass, Bioresorbable, Bioactive Thin Films, Osseointegration, Dissolution, Sputtering, PVD
Publisher URL http://pubs.acs.org/doi/10.1021/acsami.5b08957
Copyright Statement Copyright information regarding this work can be found at the following address: http://eprints.nottingh.../end_user_agreement.pdf
Additional Information This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in ACS Applied Materials and Interfaces, copyright © American Chemical Society after peer review. To access the final edited and published work see http://pubs.acs.org/doi/10.1021/acsami.5b08957.

Files

Pre-Proof-Degradation and Characterisation of Resorbable Thin Films (002).pdf (1.8 Mb)
PDF

Copyright Statement
Copyright information regarding this work can be found at the following address: http://eprints.nottingham.ac.uk/end_user_agreement.pdf





You might also like



Downloadable Citations

;