ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Lead-free alkali-modified fluoride-oxide glasses: structural, optical, and radiation shielding performance

R. Ramesh Krishnan, K. A. Naseer, M. I. Sayyed, Mohammed S. Alqahtani, and K. Marimuthu

Department of Physics, The Gandhigram Rural Institute - Deemed to be University, Gandhigram, India

E-mail: mari_ram2000@yahoo.com

Received: 6 April 2026  Accepted: 27 April 2026

Abstract:

The novelty of the study lies in the comparative analysis of alkali oxides and their corresponding fluoride counterparts as modifiers within a glass system. The melt quenching technique was employed to synthesize the glass composition; 49P₂O₅ + 20TeO₂ + 10MX + 10BaCO₃ + 10ZnF₂ + 1Sm₂O₃ (MX = Li₂CO₃, LiF, Na₂CO₃, NaF, K₂CO₃ and KF). The amorphous nature was confirmed by XRD analysis, and the optical properties, such as band gap, Urbach energy and band tail parameters, provides insights into the nature of the materials. Lower Urbach energy (∆E) values confirm the reduced disorderliness in the structure of the present glasses. The ionic and covalent nature of the glass was also examined. Radiation attenuation properties were evaluated using Phy-X software. At 0.5 cm thickness, all the prepared glasses exhibit full gamma-ray shielding at low energies (0.015–0.02 MeV), and the efficiency declines noticeably as energy increases. The TVL analysis reveals that the PTSBZ:KF sample offers optimal low-energy shielding, while the PTSBZ:NF glass sample exhibits superior attenuation at higher energies, highlighting energy-dependent performance. The results demonstrate that lower HVL, TVL, and MFP along with higher LAC and MAC values validate the present glasses as effective materials for radiation attenuation applications.

Keywords: Alkali-modified glasses; Radiation shielding; Urbach energy; Optical band gap; Mass attenuation coefficient (MAC)

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-026-04966-4

Chemical Papers 80 (8) 9507–9521 (2026)