TY - JOUR

T1 - Doping engineering in MoS2 as the cathode-host in lithium‑sulfur batteries

T2 - A first principles investigation

AU - Abbasi, Maryam

AU - Frank, Irmgard

AU - Nadimi, Ebrahim

N1 - Publisher Copyright: © 2024 Elsevier Ltd

PY - 2024/8/1

Y1 - 2024/8/1

N2 - The practical application of lithium‑sulfur batteries is hindered by the dissolution of lithium polysulfides, causing a reduction in coulombic efficiency and cyclic performance, known as the shuttle effect. Addressing this requires identifying suitable anchoring materials. Metal sulfides, particularly two-dimensional structures like MoS2, emerge as promising candidates for anchoring cathode hosts in lithium‑sulfur batteries. Their attributes include sufficient adsorption energy toward polysulfides and commendable catalytic activity compared to carbon electrodes. However, their limited electrical conductivity poses a significant obstacle to efficient electron flow. In this study, employing density functional theory (DFT), we elucidate strategies for enhancing the electrical conductivity and anchoring capabilities of the basal plane of MoS2 by introducing impurities at S and Mo sites. Our investigation encompasses a range of metal dopants, including V, Ni, Co, Mn, and Fe, and non-metal atoms such as Se and P in combination with vacancies. Through meticulous examination of formation energies and induced electrical conductivity, certain dopants, both in isolation and co-doping configurations, have been identified for further scrutiny. Our findings reveal that P and V dopants exhibit low formation energies within the MoS2 structure while they improve the electrical conductivity compared to other dopants. Additionally, they demonstrate superior adsorption energies required to immobilize lithium polysulfide species effectively. Notably, the synergistic effects observed in co-doped PV-MoS2 samples markedly enhance the binding energy of Li2Sn species on the MoS2 monolayer which is supported by the ICHOP values. This dual-doping approach also facilitates the conversion of polysulfides to final products and has the low energy barrier of Li2S decomposition that accelerates the kinetics of lithium‑sulfur batteries during the charge and discharge process. Overall, our research provides valuable insights into optimizing the electrical and anchoring properties of MoS2 for enhanced performance in lithium‑sulfur batteries.

AB - The practical application of lithium‑sulfur batteries is hindered by the dissolution of lithium polysulfides, causing a reduction in coulombic efficiency and cyclic performance, known as the shuttle effect. Addressing this requires identifying suitable anchoring materials. Metal sulfides, particularly two-dimensional structures like MoS2, emerge as promising candidates for anchoring cathode hosts in lithium‑sulfur batteries. Their attributes include sufficient adsorption energy toward polysulfides and commendable catalytic activity compared to carbon electrodes. However, their limited electrical conductivity poses a significant obstacle to efficient electron flow. In this study, employing density functional theory (DFT), we elucidate strategies for enhancing the electrical conductivity and anchoring capabilities of the basal plane of MoS2 by introducing impurities at S and Mo sites. Our investigation encompasses a range of metal dopants, including V, Ni, Co, Mn, and Fe, and non-metal atoms such as Se and P in combination with vacancies. Through meticulous examination of formation energies and induced electrical conductivity, certain dopants, both in isolation and co-doping configurations, have been identified for further scrutiny. Our findings reveal that P and V dopants exhibit low formation energies within the MoS2 structure while they improve the electrical conductivity compared to other dopants. Additionally, they demonstrate superior adsorption energies required to immobilize lithium polysulfide species effectively. Notably, the synergistic effects observed in co-doped PV-MoS2 samples markedly enhance the binding energy of Li2Sn species on the MoS2 monolayer which is supported by the ICHOP values. This dual-doping approach also facilitates the conversion of polysulfides to final products and has the low energy barrier of Li2S decomposition that accelerates the kinetics of lithium‑sulfur batteries during the charge and discharge process. Overall, our research provides valuable insights into optimizing the electrical and anchoring properties of MoS2 for enhanced performance in lithium‑sulfur batteries.

KW - Density functional theory (DFT)

KW - lithium‑sulfur battery

KW - Molybdenum disulfide (MoS)

KW - Phosphorous

KW - Shuttle effect

KW - Vanadium

UR - http://www.scopus.com/inward/record.url?scp=85195835831&partnerID=8YFLogxK

U2 - 10.1016/j.est.2024.112555

DO - 10.1016/j.est.2024.112555

M3 - Article

AN - SCOPUS:85195835831

VL - 95

JO - Journal of Energy Storage

JF - Journal of Energy Storage

M1 - 112555

ER -