Pressure-induced variations of medium-range order in B2O3 glasses

• Published in: Bulletin of materials science 2022-09, Vol.45 (4), p.190, Article 190
• Main Authors: Chakraborty, Soumee, Sivasubramanian, V, Singh, Manvendra Narayan, Upadhyay, Anuj, Sinha, Anil K, Ravindran, T R
• Format: Article
• Language: English
• Subjects: Borates; Boron; Boron oxides; Chemistry and Materials Science; Composition; Correlation; Engineering; Glass; Investigations; Lead oxides; Materials Science; Reduction; Stainless steel
• ISSN: 0973-7669; 0250-4707; 0973-7669
• DOI: 10.1007/s12034-022-02772-8

Lead-borate glasses manifest unique structure with lead oxide composition owing to their dual role of modifier and former. The medium-range signature from the first sharp diffraction peak (FSDP) in lead-borates exhibits substantial correlations due to the presence of superstructural units. Pressure plays an important role in altering bonding characteristics and hence structure in materials. To understand pressure-induced changes in the medium-range order (MRO) in lead-borate glasses, we have carried out high pressure X-ray diffraction studies in the FSDP region of these glasses up to 25 GPa. Two clear peaks, q 0 and q 1 are observed in all the modified glasses, below and above the position of the FSDP in pure B 2 O 3 glass. This shows that lead oxide alters the FSDP and causes changes in the network structure at the MRO. q 1 exhibits an increase under compression, resulting in a reduction in correlation lengths for all glass compositions. The initial steep decrease is accompanied by a lower rate of reduction at higher pressures. This shows that correlations arising from structural voids in the boron matrix exhibit similar decrease for various lead oxide compositions.