Stoichiometrically optimized e<inf>g</inf> orbital occupancy of Ni-Co oxide catalysts for Li-air batteries

Authors: Karunarathne, S., Kannangara, Y.Y., Ratwani, C.R., Sandaruwan, C., Wijesinghe, W.P.S.L., Kamali, A.R. and Abdelkader, A.M.

Journal: Nanoscale

Volume: 16

Issue: 16

Pages: 7937-7950

eISSN: 2040-3372

ISSN: 2040-3364

DOI: 10.1039/d4nr00518j

Abstract:

Li-air battery (LAB) technology is making continuous progress toward its theoretical capacity, which is comparable to gasoline. However, the sluggish reaction at the cathode is still a challenge. We propose a simple strategy to optimize the surface eg occupancy by adjusting the stoichiometric ratios of transition metal-based spinel structures through a controlled hydrothermal synthesis. Three distinct stoichiometries of Ni-Co oxides were used to demonstrate the direct correlation between stoichiometry and catalytic performance. The groundsel flower-like structure having a 1 : 1.4 Ni : Co atomic ratio with high surface area, high defect density, and an abundance of Ni3+ at the surface with semi-filled eg orbitals was found to benefit the structure promoting high catalytic activities in aqueous and aprotic media. The assembled LAB cells employing this cathode demonstrate an exceptional lifespan, operating for 3460 hours and completing 173 cycles while achieving the highest discharge capacity of 13 759 mA h g−1 and low charging overpotentials. The key to this prolonged performance lies in the full reversibility of the cell, attributed to its excellent OER performance. A well-surface adsorbed, amorphous LiO2/Li2O2 discharge product is found to possess high diffusivity and ease of decomposition, contributing significantly to the enhanced longevity of the cell.

https://eprints.bournemouth.ac.uk/39766/

Source: Scopus

Stoichiometrically optimized eg orbital occupancy of Ni-Co oxide catalysts for Li-air batteries.

Authors: Karunarathne, S., Kannangara, Y.Y., Ratwani, C.R., Sandaruwan, C., Wijesinghe, W.P.S.L., Kamali, A.R. and Abdelkader, A.M.

Journal: Nanoscale

Volume: 16

Issue: 16

Pages: 7937-7950

eISSN: 2040-3372

DOI: 10.1039/d4nr00518j

Abstract:

Li-air battery (LAB) technology is making continuous progress toward its theoretical capacity, which is comparable to gasoline. However, the sluggish reaction at the cathode is still a challenge. We propose a simple strategy to optimize the surface eg occupancy by adjusting the stoichiometric ratios of transition metal-based spinel structures through a controlled hydrothermal synthesis. Three distinct stoichiometries of Ni-Co oxides were used to demonstrate the direct correlation between stoichiometry and catalytic performance. The groundsel flower-like structure having a 1 : 1.4 Ni : Co atomic ratio with high surface area, high defect density, and an abundance of Ni3+ at the surface with semi-filled eg orbitals was found to benefit the structure promoting high catalytic activities in aqueous and aprotic media. The assembled LAB cells employing this cathode demonstrate an exceptional lifespan, operating for 3460 hours and completing 173 cycles while achieving the highest discharge capacity of 13 759 mA h g-1 and low charging overpotentials. The key to this prolonged performance lies in the full reversibility of the cell, attributed to its excellent OER performance. A well-surface adsorbed, amorphous LiO2/Li2O2 discharge product is found to possess high diffusivity and ease of decomposition, contributing significantly to the enhanced longevity of the cell.

https://eprints.bournemouth.ac.uk/39766/

Source: PubMed

Stoichiometrically optimized e<sub>g</sub> orbital occupancy of Ni-Co oxide catalysts for Li-air batteries

Authors: Karunarathne, S., Kannangara, Y.Y., Ratwani, C.R., Sandaruwan, C., Wijesinghe, W.P.S.L., Kamali, A.R. and Abdelkader, A.M.

Journal: NANOSCALE

Volume: 16

Issue: 16

Pages: 7937-7950

eISSN: 2040-3372

ISSN: 2040-3364

DOI: 10.1039/d4nr00518j

https://eprints.bournemouth.ac.uk/39766/

Source: Web of Science (Lite)

Stoichiometrically optimized e<sub>g</sub> orbital occupancy of Ni-Co oxide catalysts for Li-air batteries.

Authors: Karunarathne, S., Kannangara, Y.Y., Ratwani, C.R., Sandaruwan, C., Wijesinghe, W.P.S.L., Kamali, A.R. and Abdelkader, A.M.

Journal: Nanoscale

Volume: 16

Issue: 16

Pages: 7937-7950

eISSN: 2040-3372

ISSN: 2040-3364

DOI: 10.1039/d4nr00518j

Abstract:

Li-air battery (LAB) technology is making continuous progress toward its theoretical capacity, which is comparable to gasoline. However, the sluggish reaction at the cathode is still a challenge. We propose a simple strategy to optimize the surface eg occupancy by adjusting the stoichiometric ratios of transition metal-based spinel structures through a controlled hydrothermal synthesis. Three distinct stoichiometries of Ni-Co oxides were used to demonstrate the direct correlation between stoichiometry and catalytic performance. The groundsel flower-like structure having a 1 : 1.4 Ni : Co atomic ratio with high surface area, high defect density, and an abundance of Ni3+ at the surface with semi-filled eg orbitals was found to benefit the structure promoting high catalytic activities in aqueous and aprotic media. The assembled LAB cells employing this cathode demonstrate an exceptional lifespan, operating for 3460 hours and completing 173 cycles while achieving the highest discharge capacity of 13 759 mA h g-1 and low charging overpotentials. The key to this prolonged performance lies in the full reversibility of the cell, attributed to its excellent OER performance. A well-surface adsorbed, amorphous LiO2/Li2O2 discharge product is found to possess high diffusivity and ease of decomposition, contributing significantly to the enhanced longevity of the cell.

https://eprints.bournemouth.ac.uk/39766/

Source: Europe PubMed Central

Stoichiometrically optimized eg orbital occupancy of Ni-Co oxide catalysts for Li-air batteries

Authors: Karunarathne, S., Kannangara, Y.Y., Ratwani, C.R., Sandaruwan, C., Wijesinghe, W.P.S.L., Kamali, A.R. and Abdelkader, A.M.

Journal: Nanoscale

Volume: 16

Pages: 7937-7950

ISSN: 2040-3364

Abstract:

Li-air battery (LAB) technology is making continuous progress toward its theoretical capacity, which is comparable to gasoline. However, the sluggish reaction at the cathode is still a challenge. We propose a simple strategy to optimize the surface eg occupancy by adjusting the stoichiometric ratios of transition metal-based spinel structures through a controlled hydrothermal synthesis. Three distinct stoichiometries of Ni-Co oxides were used to demonstrate the direct correlation between stoichiometry and catalytic performance. The groundsel flower-like structure having a 1 : 1.4 Ni : Co atomic ratio with high surface area, high defect density, and an abundance of Ni3+ at the surface with semi-filled eg orbitals was found to benefit the structure promoting high catalytic activities in aqueous and aprotic media. The assembled LAB cells employing this cathode demonstrate an exceptional lifespan, operating for 3460 hours and completing 173 cycles while achieving the highest discharge capacity of 13 759 mA h g-1 and low charging overpotentials. The key to this prolonged performance lies in the full reversibility of the cell, attributed to its excellent OER performance. A well-surface adsorbed, amorphous LiO2/Li2O2 discharge product is found to possess high diffusivity and ease of decomposition, contributing significantly to the enhanced longevity of the cell.

https://eprints.bournemouth.ac.uk/39766/

Source: BURO EPrints