Sodium–tungsten–titanium phosphate glasses: an investigation of the structure, chemical endurance, and kinetic characteristics

Many technologies have applied sodium ions’ solid electrolytes, ranging from batteries to chemical sensors. This study investigated phosphate glasses featuring electrolyte developed through the 20Na 2 O–(50 − x )Na 2 WO 4 – x TiO 2 –30P 2 O 5 system (with 0 ≤ x ≤ 25 mol%), with the melt-quenching approach employed. For the estimation of the activation energy, differential scanning calorimetry was utilized, whereby crystallization ( E c ) was relied upon. E c = 144.77 kJ/mol characterized the glass ( x = 5). The determination of the crystallization mechanism was possible through the Avrami parameter ( n ), which was found to be approximately ≈ 2; therefore, the crystallization mechanism was expected to be a periodic landscape that is one-dimensional in nature. The bonds forming the glasses’ framework were shown to be established through the PO 4 units, as revealed by Raman spectroscopy. TiO 2 insertion into the framework of glass resulted in new bond formation, namely P–O–Ti and/or Ti–O–Ti. Shifting the Na 2 WO 4 mol% to TiO 2 mol% resulted in the structural units’ transformation into Q 2 , Q 1 , and finally Q 0 units. Through the durability analysis, the results confirmed that the explored glasses’ dissolution is reliant upon their composition, which is of a glassy nature. There is an increase in durability when Na 2 WO 4 is replaced by TiO 2 .