Magnesium insertion and related structural changes in spinel-type manganese oxides

Robba, Ana (avtor), Tchernychova, Elena (avtor), Bitenc, Jan (avtor), Randon-Vitanova, Anna (avtor), Dominko, Robert (avtor)

Commercial LiMn$_2$O$_4$ powder was used as the base material for probing magnesiation, cycling behavior, and structural stability/changes in (Mg$_x$Li$_{1-x}$)Mn$_2$O$_4$ spinel cathodes in aqueous Mg(NO$_3$)$_2$ and non-aqueous Mg(TFSI)$_2$/diglyme and Mg(Mg(HFIP)$_2$ − 2Al(HFIP)$_3$/diglyme electrolytes. Each of the samples was delithiated and, then, magnesiated electrochemically in the corresponding electrolyte. The electrochemical activity of the cathode cycled in aqueous electrolyte showed high reversibility during the oxidation process; however, large polarization and a relatively fast capacity fading were the culprits of the system. Cycling in Mg(TFSI)2/diglyme electrolyte solution resulted in much lower initial specific capacity compared to an aqueous counterpart, as well as a much faster failure. On the other hand, cycling in Mg(HFIP)$_2$ − 2Al(HFIP)$_3$/diglyme electrolyte solution demonstrated excellent cycling performance with very low polarization in the first cycles. The observed voltages for this system were near theoretical values for the Mg insertion. Although the electrochemical measurements suggest reversible magnesiation, detailed structural and analytical STEM investigation revealed the differences in the atomic structure and Mn valence of all three cathode samples upon cycling. The electrolytes’ influence on the structural rearrangement during Mg insertion is discussed for each of the three systems.

• Jezik: Angleški jezik
• Ključne besede: spinel, manganese, lithium, magnesium, TEM, electrochemistry
• 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: 2021
• Št. strani: 12 str.
• Številčenje: Vol. 11, iss. 8, art. 984
• PID: 20.500.12556/RUL-135999
• UDK: 544.1:544.6
• ISSN pri članku: 2073-4352
• DOI: 10.3390/cryst11080984
• COBISS.SI-ID: 78444291
• Datum objave v RUL: 06.04.2022

Gradivo je del revije

• Naslov: Crystals
• Skrajšan naslov: Crystals
• Založnik: MDPI
• ISSN: 2073-4352
• COBISS.SI-ID: 36677893

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.
• Začetek licenciranja: 19.08.2021

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: spinel, mangan, litij, magnezij, TEM, elektrokemija

Projekti

• Financer: ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
• Številka projekta: P2-0393
• Naslov: Napredni materiali za nizkoogljično in trajnostno družbo

• Financer: Drugi - Drug financer ali več financerjev
• Program financ.: Honda R&D Europe