Effect of controlled crystallization on polaronic transport in phosphate‐based glass‐ceramics

Znanstveni rad - Izvorni znanstveni rad

• Autor: Luka Pavić; MBZ: 312881
• Autor: Juraj Nikolić; MBZ: 360406
• Autor: Manuel P. F. Graça
• Autor: Benilde F. O. Costa
• Autor: Manuel A. Valente
• Autor: Željko Skoko; MBZ: 236445
• Autor: Ana Šantić; MBZ: 236704
• Autor: Andrea Moguš- Milanković; MBZ: 78861
• Autorova ustanova: Sveučilište u Zagrebu; Prirodoslovno-matematički fakultet; (Fizički odsjek)
• Znanstveno / umjetničko područje, polje i grana: PRIRODNE ZNANOSTI; Fizika
• Znanstveno / umjetničko područje, polje i grana: PRIRODNE ZNANOSTI; Kemija

Sažetak (engleski)

The effect of induced crystallization on changes in electrical transport of two types of glass‐ceramics, pure polaron conductive 40Fe2O3‐60P2O5 (F40) (mol%) and predominantly polaronic 5Li2O‐5ZnO‐40P2O5‐50WO3 (Li‐50W) (mol%) was investigated. F40 glass‐ceramics produced at low heat‐treatment temperatures contain single‐phase Fe3(P2O7)2 whereas at higher temperatures two more phases Fe4(P2O7)3 and Fe(PO3)3 are formed. Structural modifications strongly depend on the crystallization temperature and time. The appearance of crystalline phases studied by Mössbauer spectroscopy exhibits changes in Fe2+/Fetot ratio in crystalline/glassy phases. The detailed analysis of different iron sites allows their correlation with changes in electrical conductivity as crystallization progresses. Depending on the course of crystallization, the contribution of each phase to the overall conductivity is determined by the frequency dependence of Zʺ(ω) and Mʺ(ω). DC conductivity shows a sharp decrease as Fe3(P2O7)2 phase appears and consequently glass matrix remains impoverished in Fe2+‐Fe3+ pairs. In the multiphase systems prepared at higher crystallization temperatures, the overall electrical conductivity increases although the continuous grain boundaries along different crystalline grains play a limiting factor. In contrast, the slight conductivity change in Li‐ 50W glass‐ceramics upon crystallization is a result of remaining W5+‐W6+ pairs in the residual glassy phase. Independence of electrical transport on Li+ ions confirms predominantly polaronic transport in Li‐50W glass‐ceramics.

• Ključne riječi (engleski): Glass ceramics; Induced crystallization; Iron phosphate glass; Mössbauer spectroscopy; Polaronic transport; Structural 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 Applied Glass Science
• Brojčani podaci: vol. 11, br. 1, str. 97-111
• p-ISSN: 2041-1286
• e-ISSN: 2041-1294
• DOI: https://doi.org/10.1111/ijag.13618
• URN:NBN: urn:nbn:hr:217:140991
• Datum objave publikacije: 2020
• URL dokumenta: https://ceramics.onlinelibrary.wiley.com/doi/abs/10.1111/ijag.13618
• Vrsta resursa: Tekst
• Prava pristupa: Otvoreni pristup
• Javna napomena: Received: 31 May 2019. Revised: 1 August 2019. Accepted: 22 August 2019.
• Datum i vrijeme pohrane: 2020-08-18 20:40:29