Microwave Exfoliated Few-Layered Graphene Cathode for Aluminum Batteries
Petnikota, Shaikshavali; Dos Reis, Glaydson Simões; Kayakool, Fathima Ali; Vadali, Venkata Satya Siva Srikanth; Välikangas, Juho; Lassi, Ulla; Thyrel, Mikael (2024-08-14)
American chemical society
14.08.2024
Petnikota, S., Simões Dos Reis, G., Kayakool, F. A., Vadali, V. S. S. S., Välikangas, J., Lassi, U., & Thyrel, M. (2024). Microwave exfoliated few-layered graphene cathode for aluminum batteries. ACS Applied Energy Materials, 7(16), 6862–6872. https://doi.org/10.1021/acsaem.4c00444.
https://creativecommons.org/licenses/by/4.0/
© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.
https://creativecommons.org/licenses/by/4.0/
© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.
https://creativecommons.org/licenses/by/4.0/
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:oulu-202408265584
https://urn.fi/URN:NBN:fi:oulu-202408265584
Tiivistelmä
Abstract
Microwave-exfoliated few-layered graphene (meFLG) with oxygen, hydroxyl, and sulfate impurities is tested as a cathode material in aluminum batteries (ABs). The O and S impurities bonded to C atoms are found collectively weighing 2.9–4.7 at. % (4.1–6.9 wt %). meFLG as a cathode in AB pouches delivered stable discharge capacities around 100 mAh/g at 0.1 A/g current rate over 500 cycles, despite high irreversible capacities noticed for the first few cycles. Side reactions of the impurities with the electrolyte species are found to be responsible for the initial high irreversible capacities. The effect of the impurities became negligible when meFLG cycled at higher current rates starting from 1.0 A/g, but initial energy storage capacities and cyclic behavior varied with the voltage window. Postcycling chemical analysis of the electrode matrix revealed that anion species (AlCl4–) of the electrolyte are found covalently bonded to the impurities, while cation species are found intact even after 500 cycles of continuous charge–discharges. We therefore recommend careful characterization of the impurities before using FLG-related materials as aluminum battery cathode materials. Removing the impurities before the electrode fabrication will help meFLG outperform its class of materials because it shows excellent rate capability even with the impurities.
Microwave-exfoliated few-layered graphene (meFLG) with oxygen, hydroxyl, and sulfate impurities is tested as a cathode material in aluminum batteries (ABs). The O and S impurities bonded to C atoms are found collectively weighing 2.9–4.7 at. % (4.1–6.9 wt %). meFLG as a cathode in AB pouches delivered stable discharge capacities around 100 mAh/g at 0.1 A/g current rate over 500 cycles, despite high irreversible capacities noticed for the first few cycles. Side reactions of the impurities with the electrolyte species are found to be responsible for the initial high irreversible capacities. The effect of the impurities became negligible when meFLG cycled at higher current rates starting from 1.0 A/g, but initial energy storage capacities and cyclic behavior varied with the voltage window. Postcycling chemical analysis of the electrode matrix revealed that anion species (AlCl4–) of the electrolyte are found covalently bonded to the impurities, while cation species are found intact even after 500 cycles of continuous charge–discharges. We therefore recommend careful characterization of the impurities before using FLG-related materials as aluminum battery cathode materials. Removing the impurities before the electrode fabrication will help meFLG outperform its class of materials because it shows excellent rate capability even with the impurities.
Kokoelmat
- Avoin saatavuus [41246]
Ellei muuten mainita, aineiston lisenssi on https://creativecommons.org/licenses/by/4.0/