Two-Dimensional α-SiX (X = N, P) Monolayers as Efficient Anode Material for Li-Ion Batteries: A First-Principles Study

Abstract

Density functional theory simulations were performed to investigate the structural, electronic, and electrochemical properties of the two-dimensional α-SiX (X = N, P) monolayers as anode material in Li-ion batteries (LIBs). Our result indicates that α-SiX monolayers have excellent mechanical, dynamical, and thermal stability. The obtained adsorption energy values suggest that the Li atom adsorption over α-SiX is a favorable process. According to the Löwdin charge transfer and partial density of states analysis, charge transfer takes place from Li atom to α-SiX monolayers. From the band structure plots, we observed that after the adsorption of a single Li atom, the α-SiX monolayers are converted into a metallic state from the semiconductor state and remain in the metallic state for the different adsorption concentrations of Li atoms, which is essential to facilitate the diffusion of stored electrons. The calculated specific storage capacity is 956.16 and 733.66 mA h g–1 for α-SiN and α-SiP monolayers, respectively, which is remarkably higher than that of the conventional anode materials (such as graphite and TiO2). Ab initio molecular dynamics simulations confirm the room-temperature stability of the α-SiX monolayers at the maximum loading of Li atoms. The lower diffusion energy barriers of 0.30 eV (for α-SiN monolayers) and 0.16 eV (for α-SiP monolayers) ensure good diffusivity of ions over monolayers. The calculated open-circuit voltage is also favorable for battery applications. The aforementioned findings suggest that the α-SiX monolayers could be beneficial and compelling host anode material for high-performance LIBs.

Monolayer Tic− a High-Performance Dirac Anode with Ultralow Diffusion Barriers and High Energy Densities for Li-Ion and Na-Ion Batteries

“…Furthermore, ML TiC demonstrated high ionic conductivity for Li and Na-ions, with ultralow diffusion barriers of 0.022 and 0.10 eV, respectively. The fully Li and Na intercalated TiC [11] 0.15 401 borophane [20] 1172 0.09 1353 borophene [65,66] 0.003 2659 0.03 1978 MoS 2 [22] 0.17 2211 0.04 632 black phosphorene [11] 0.04 841 YS 2 [67] 0.33 212 0.24 243 h-BAs [24] 0.52 1065 0.25 1491 𝛽-Sb [25] 0.1 1073 NiS 2 [68] 0.23 894 0.12 1266 V 2 N [69] 0.03 2890 0.01 1929 V 2 B 2 [70] 0.01 1252 B 2 S 2 [71] 0.27 1174 𝛼-SiN [72] 0.3 423 Pentagraphyne [73] 0.49 517 0.612 497 CoB [63] 0.32 1463 CoAs [63] 0.46 1381 p-BP [74] 0.13 295 0. 16 71 anode exhibited a volume expansion as low as 0.13 and 0.11%, respectively, showing excellent cycling stability.…”

β12-Borophene/Graphene Heterostructure as a High-Performance Anode Material for Li-Ion Batteries

“…Furthermore, we employed the climbing image nudged elastic band (CI-NEB) method to define the pathways for Li atom diffusion on the layers. This involved considering the fully optimized and exceptionally favored adsorption site from both the initial and final structures within a 1 × 2 × 1 supercell of the heterostructure …”

“…This involved considering the fully optimized and exceptionally favored adsorption site from both the initial and final structures within a 1 × 2 × 1 supercell of the heterostructure. 46…”

First-Principles Studies on High-Entropy Ti0.75V0.75Cr0.75Mo0.75C2 MXene Nanosheets as Anode Materials in Zinc-Ion Batteries

“…1,4−6 Over the past few decades, two-dimensional (2D) materials have received wide attention due to their innovative electronic, photonic, magnetic, and electrochemical properties 7−12 since the discovery of graphene in 2004. 13 (TMOs), 14 transition metal dichalcogenides (TMDs), 15 phosphorene, 16,17 carbon-and nitrogen-based materials, 18−22 transition metal carbides and nitrides (MXenes), 23−28 and other 2D structures 29,30 have been explored due to their excellent electrochemical performance, which are significant for variable portable devices and electric vehicles. 31,32 TMOs and TMDs as anode materials possess advantages like high capacity and low cost, but their resistance is large, and the volume expansion is obviously large and irreversible capacity loss occurs during cycles.…”

“…Over the past few decades, two-dimensional (2D) materials have received wide attention due to their innovative electronic, photonic, magnetic, and electrochemical properties − since the discovery of graphene in 2004 . Transition metal oxides (TMOs), transition metal dichalcogenides (TMDs), phosphorene, , carbon- and nitrogen-based materials, − transition metal carbides and nitrides (MXenes), − and other 2D structures , have been explored due to their excellent electrochemical performance, which are significant for variable portable devices and electric vehicles. , TMOs and TMDs as anode materials possess advantages like high capacity and low cost, but their resistance is large, and the volume expansion is obviously large and irreversible capacity loss occurs during cycles. , The theoretical capacity of phosphorene is high, but the preparation is time-consuming with low yields, and the structural changes are large during reactions. , Although graphene is widely used as anode materials with high energy density, the power density is low and the capacity is limited . The band gap of h-BN is so large that it is not suitable as an electrode material .…”