Insights into structural, thermal, physical, optical, and electrical properties of novel ZnO-doped lithium–titanium-phosphate glasses

This study investigates novel ZnO-doped lithium-titanium-phosphate glasses, synthesized via the melt-quenching method, and characterizes their physical, structural, thermal, optical, chemical, mechanical, and electrical properties, with a focus on the impact of varying ZnO content on these properties. An increase in ZnO content from 20 mol% to 27.27 mol% induces significant local structural changes, promoting enhanced network polymerization, density, and chemical durability, while concurrently reducing thermal stability and mechanical strength. EPR analysis confirmed that titanium remained in the Ti4+ state, while optical measurements revealed an increased band gap, attributed to the role of ZnO in preventing Ti4+ reduction and minimizing localized states. The electrical conductivity decreases with increasing ZnO content, with the highest value measured at 1.73 × 10-10 Ω-1 cm-1. High-ZnO glasses exhibit mainly electronic conductivity of 4.02 × 10-9 Ω-1 cm-1 at room temperature. The frequency-dependent conductivity follows Jonscher's power law, with the charge transport governed by a correlated barrier-hopping mechanism, remaining stable across temperatures and compositions.