Exploring the Effect of V2O5 and Nb2O5 Content on the Structural, Thermal, and Electrical Characteristics of Sodium Phosphate Glasses and Glass–Ceramics

Znanstveni rad - Izvorni znanstveni rad

• Autor: Sara Marijan
• Autor: Teodoro Klaser
• Autor: Marija Mirosavljević
• Autor: Petr Mošner
• Autor: Ladislav Koudelka
• Autor: Željko Skoko
• Autor: Jana Pisk
• Autor: Luka Pavić
• Autorova ustanova: Sveučilište u Zagrebu; Prirodoslovno-matematički fakultet; (Fizički odsjek)
• Znanstveno / umjetničko područje, polje i grana: PRIRODNE ZNANOSTI; Fizika

Sažetak (engleski)

Na-V-P-Nb-based materials have gained substantial recognition as cathode materials in high-rate sodium-ion batteries due to their unique properties and compositions, comprising both alkali and transition metal ions, which allow them to exhibit a mixed ionic–polaronic conduction mechanism. In this study, the impact of introducing two transition metal oxides, V2O5 and Nb2O5, on the thermal, (micro)structural, and electrical properties of the 35Na2O-25V2O5-(40 − x)P2O5 − xNb2O5 system is examined. The starting glass shows the highest values of DC conductivity, σDC, reaching 1.45 × 10−8 Ω−1 cm−1 at 303 K, along with a glass transition temperature, Tg, of 371 °C. The incorporation of Nb2O5 influences both σDC and Tg, resulting in non-linear trends, with the lowest values observed for the glass with x = 20 mol%. Electron paramagnetic resonance measurements and vibrational spectroscopy results suggest that the observed non-monotonic trend in σDC arises from a diminishing contribution of polaronic conductivity due to the decrease in the relative number of V4+ ions and the introduction of Nb2O5, which disrupts the predominantly mixed vanadate–phosphate network within the starting glasses, consequently impeding polaronic transport. The mechanism of electrical transport is investigated using the model-free Summerfield scaling procedure, revealing the presence of mixed ionic–polaronic conductivity in glasses where x < 10 mol%, whereas for x ≥ 10 mol%, the ionic conductivity mechanism becomes prominent. To assess the impact of the V2O5 content on the electrical transport mechanism, a comparative analysis of two analogue series with varying V2O5 content (10 and 25 mol%) is conducted to evaluate the extent of its polaronic contribution.

• Ključne riječi (engleski): phosphate glasses; phosphate glass–ceramics; (micro)structure–property relationship; PXRD; SEM-EDS; EPR; vibrational spectroscopy; impedance spectroscopy; electrical properties
• Jezik: engleski
• Vrsta publikacije: Znanstveni rad - Izvorni znanstveni rad
• Status objave: Objavljen
• Vrsta recenzije: Recenziran - međunarodna recenzija
• Verzija publikacije: Objavljena verzija rada (izdavačev PDF)
• Naslov časopisa: International Journal of Molecular Sciences
• Brojčani podaci: vol. 25, br. 5, 3005
• e-ISSN: 1422-0067
• DOI: https://doi.org/10.3390/ijms25053005
• URN:NBN: urn:nbn:hr:217:370725
• Datum objave publikacije: 2024-03-05
• Projekt: Šifra: IP-2018-01-5425; Naziv (hrvatski): Detaljan uvid u mehanizme polaronske i ionske vodljivosti u oksidnoj staklo-(keramici); Kratica: POLAR-ION-GLASS; Voditelj: Ana Šantić; Pravna nadležnost: Hrvatska; Financijer: Hrvatska zaklada za znanost; Linija financiranja: Research Projects
• URL dokumenta: https://www.mdpi.com/1422-0067/25/5/3005
• Vrsta resursa: Tekst
• Prava pristupa: Otvoreni pristup
• Javna napomena: © 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). Received: 16 February 2024. Revised: 28 February 2024. Accepted: 1 March 2024. Published: 5 March 2024.
• Datum i vrijeme pohrane: 2024-07-24 10:31:33