Synthesis and characterization of a new high-entropy oxide based on rare-earth elements (Dy,Y,Yb,Nd,Pr)O$_{1.5\pm\delta}$ prepared by citrate–nitrate combustion synthesis

Skalar, Tina (avtor), Levičar, Maks (avtor), Marinšek, Marjan (avtor), Genorio, Boštjan (avtor), Ptáček, Petr (avtor), Blahut, Jan (avtor), Sokola, Patrik (avtor)

High-entropy oxides represent a modern class of materials with broad applicability, in which the configurational entropy of multiple equimolar cations stabilises single-phase structures with unique defect chemistry and tunable functional properties. In the proposed work, a novel rare-earth high-entropy oxide with the composition (Dy,Y,Yb,Nd,Pr)O$_{1.5\pm\delta}$ was synthesized via citrate–nitrate combustion synthesis, followed by calcination in the temperature range 600-1100 °C. Thermogravimetry coupled with mass spectrometry revealed multi-stage decomposition and carbon removal, defining the temperatures required for complete oxidation of carbonaceous residues. High-temperature and ambient XRD analyses confirmed the formation of a single-phase cubic oxide with progressive crystallite growth from ∼10 to 40 nm upon calcination. Optical reflectance measurements showed a semiconducting band gap from 2.26 to 2.39 eV and Urbach energies that reflect changes in structural disorder during calcination. SEM/EDS analyses demonstrated the formation of homogeneous nanocrystals, with surface areas up to 31 m$^2$g$^{−1}$. The study provides a detailed description of phase evolution, defect chemistry, and disorder formation in a combustion-derived rare-earth high-entropy oxide with potential applications in the semiconductor industry.

• Jezik: Angleški jezik
• Ključne besede: high-entropy ceramics, combustion synthesis, thermal analysis, band gap
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FKKT - Fakulteta za kemijo in kemijsko tehnologijo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2026
• Št. strani: 11 str.
• Številčenje: Vol. , iss.
• PID: 20.500.12556/RUL-181380
• UDK: 620.1
• ISSN pri članku: 0272-8842
• DOI: 10.1016/j.ceramint.2026.03.405
• COBISS.SI-ID: 274021891
• Datum objave v RUL: 03.04.2026

Gradivo je del revije

• Naslov: Ceramics international
• Skrajšan naslov: Ceram. int.
• Založnik: Elsevier
• ISSN: 0272-8842
• COBISS.SI-ID: 5822215

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: keramika z visoko entropijo, zgorevalna sinteza, termična analiza, pasovna vrzel

Projekti

• Financer: ARIS - Javna agencija za znanstvenoraziskovalno in inovacijsko dejavnost Republike Slovenije
• Številka projekta: P1-0175
• Naslov: Napredna anorganska kemija

• Financer: ARIS - Javna agencija za znanstvenoraziskovalno in inovacijsko dejavnost Republike Slovenije
• Številka projekta: I0-0022
• Naslov: Mreža raziskovalnih infrastrukturnih centrov Univerze v Ljubljani (MRIC UL)