Glassy and glass-ceramic materials based on V₂O₅-P₂O₅ have been identified as highly promising cathode materials for rechargeable Li-ion, Na-ion, and all-solid-state batteries. These materials offer a compelling combination of high safety, exceptional energy density, and extended cycling life, making them highly promising¹. In addition, such materials are also recognized as effective catalysts in oxidation reactions². Furthermore, it has been acknowledged that the microstructural properties, electrical conductivity, and electrochemical properties of V₂O₅-P₂O₅-based glasses can be significantly improved through thermally controlled crystallization³. In light of this, this study aims to synthesize a glass with a nominal composition of 70V₂O₅-20Nb₂O₅-10P₂O₅ and investigate the influence of controlled crystallization at different temperatures and durations on the electrical and catalytic properties. The parent glass is prepared via the melt-quenching technique, and its thermal behavior is examined through differential thermal analysis (DTA). The samples subjected to controlled crystallization are qualitatively and quantitatively analyzed using powder X-ray diffraction (PXRD), while (micro)structural properties are assessed using scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and infrared attenuated total reflectance spectroscopy (IR-ATR). Electrical transport is investigated by solid-state impedance spectroscopy (SS-IS) across a wide frequency (0.01 Hz to 1 MHz) and temperature range (–90 °C to 240 °C). The catalytic activity of prepared samples is tested in oxidation reactions of stearic acid and is monitored using TG-IR system. The findings of this research demonstrate a remarkable enhancement in electrical conductivity through thermal treatment of the parent glass, with the sample heat-treated at 380 °C exhibiting the highest conductivity of 1.58 × 10^–3 S/cm @30 °C. Furthermore, these materials exhibit promising catalytic properties, unveiling new avenues for their application.

ACKNOWLEDGMENTS
This work is supported by the Croatian Science Foundation under the projects IP-2018-01-5425 and DOK-2021-02-9665.

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