Synthesis and use of pyrazine and quinone based cathode materials in lithium and zinc batteries

Menart, Svit (author), Pirnat, Klemen (mentor)

Despite the rapid expansion of the organic cathode materials field, we still a face shortage of materials obtained through simple synthesis that exhibit stable cycling and high energy density. The large-scale deployment of battery technology is driving the research towards the use of more sustainable and less scarce anode materials, with zinc metal being recognized as one of the most promising alternatives. The thesis focuses on the development of novel organic cathode materials with increased energy density derived from facile synthesis procedures, which were applied in lithium and zinc batteries. Apart from the performance evaluation, we show additional in-depth analysis of the redox reaction and degradation mechanisms with the use of ex-situ FT-IR spectroscopy, ex-situ SEM analysis, and three-electrode cyclic voltammetry experiments. The first part of the thesis is dedicated to small organic cathode materials derived from the reaction between aromatic diamines and sodium rhodizonate or hexaketocyclohexane octahydrate. In lithium battery configuration the derived materials showed high energy density (up to 860 Wh kg$^{-1}$) and excellent cycling stability (up to 82 % capacity retention after 400 cycles at 50 mAg$^{-1}$). Although the high energy density (up to 280 Wh kg$^{-1}$) was retained in zinc battery configuration employing aqueous electrolytes, the cycling stability was compromised with the best-performing material showing 88 % capacity retention after 100 cycles at 100 mAg$^{-1}$. The second part of the thesis encompasses the development of novel Schiff base polymers. The design of materials mitigated the use of redox inactive linkers, which limit the capacity of the polymer cathode materials. We explored a Schiff base polymer derived from reaction between 2,5-dihydroxybenzene-1,4-dicarbaldehyde (DHDC) and 2,6-diaminoanthraquinone. The synthesized polymer SBP1 exhibited a maximum capacity of 240 mAhg$^{-1}$ and stable performance in lithium battery with a capacity retention of 83 % after 140 cycles at 50 mAg$^{-1}$.

• Language: English
• Keywords: lithium battery, zinc battery, cathode, pyrazine, quinone
• Work type: Doctoral dissertation
• Typology: 2.08 - Doctoral Dissertation
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Year: 2024
• PID: 20.500.12556/RUL-164933
• COBISS.SI-ID: 218503427
• Publication date in RUL: 18.11.2024

Secondary language

• Language: Slovenian
• Title: Sinteza in uporaba pirazinskih in kinonskih katodnih materialov v litijevih in cinkovih akumulatorjih

Abstract

Kljub hitremu razvoju področja organskih katodnih materialov se še vedno soočamo s pomanjkanjem materialov, pridobljenih s preprosto sintezo, ki omogočajo stabilno delovanje in visoko energijsko gostoto. Zaradi vedno večjih potreb po shranjevanju energije se raziskave usmerjajo v uporabo bolj trajnostnih katodnih materialov in bolj dostopnih anodnih materialov, pri čemer je kovinski cink prepoznan kot ena izmed najbolj obetavnih alternativ. Doktorsko delo se osredotoča na razvoj novih organskih katodnih materialov za uporabo v litijevih in cinkovih akumulatorjih, ki so pridobljeni z enostavnimi sinteznimi postopki in omogočajo povečano energijsko gostoto. Poleg ovrednotenja delovanja materialov v akumulatorjih predstavljamo tudi poglobljeno analizo redoks in degradacijskih mehanizmov, pridobljenih z ex situ FT-IR spektroskopijo, ex-situ SEM analizo in troelektrodno ciklično voltametrijo. V prvem delu doktorskega dela smo se posvetili sintezi majhnih organskih katodnih materialov, ki so pridobljeni s kondenzacijsko reakcijo med aromatskimi diamini in natrijevim rodizonatom oz. heksaketocikloheksan oktahidratom. V litijevem akumulatorju so materiali dosegli visoke energijske gostote (do 860 Wh kg$^{-1}$) in visoke stabilnosti dolgoročnega polnjenja/praznjenja z do 82-% ohranitvijo kapacitete po 400 ciklih pri 50 mAg$^{-1}$. Sintetizirani materiali so visoke energijske gostote ohranili tudi v vodnih cinkovih akumulatorjih (do 280 Wh kg$^{-1}$), a so po drugi strani pokazali slabšo dolgoročno stabilnost, saj je najboljši material po 100 ciklih pri 100 mAg$^{-1}$ ohranil 88 % kapacitete. Drugi del doktorskega dela zajema razvoj novih organskih katodnih polimernih materialov na osnovi Shiffovih baz. Z našim pristopom smo želeli omejiti uporabo redoks neaktivnih veznih členov, ki zmanjšujejo kapaciteto katodnih materialov. Raziskali smo polimer na osnovi Schiffovih baz, ki smo ga sintetizirali z uporabo enostavne kondenzacijske reakcije med komercialno dobavljivim 2,5-dihidroksibenzen-1,4-dikarboksaldehidom (DHDC) in 2,6-diaminoantrakinonom. Sintetizirani polimer SBP1 je dosegel najvišjo kapaciteto 240 mAhg$^{-1}$ (Cteo. = 289 mAhg$^{-1}$, 4 e$^-$) in izkazal stabilno delovanje v litijevem akumulatorju s 83-% ohranitvijo kapacitete po 140 ciklih pri 50 mAg$^{-1}$.

• Keywords: litijev akumulator, cinkov akumulator, katoda, pirazini, kinoni