Anode Material For Mg-ion Batteries Research Articles

Unlocking the potential of Mg-ion batteries: Cu2C MXene anode with ultrahigh storage and energy density with rapid Mg diffusion

Magnesium-ion batteries hold immense promise for the future of electrical energy storage due to the abundant availability of magnesium metal and the efficient energy storage capacity of divalent magnesium ions which has the potential to revolutionize both large-scale stationary applications and portable devices. MXenes, encompassing transition metal carbides/nitrides/carbonitrides, are still considered newcomers in the domain of 2D nanomaterials, especially regarding their utilization in energy storage applications. In this work, we employed first principles based DFT calculations to comprehensively evaluate the electrochemical behavior of 2H phase Cu-based MXene (Cu2C) monolayer as promising anode material for Mg-ion batteries. The stability of the Cu2C monolayer was assessed through calculations of negative cohesive energy, positive phonon frequencies, and AIMD simulations to confirm stability at room temperature along with superior mechanical strength. The simulation outcomes show that strong affinity for Mg ions to the Cu2C monolayer, which is attributed to metallic character, suggesting good electronic conductivity and aslo, the calculated negative adsorption energy of −1.25 eV, indicating a favorable interaction for potential battery applications. The Cu2C monolayer emerges as a compelling candidate for anode materials due to its exceptional combination of high theoretical specific capacity (1541.36 mAh/g) and a low average operating voltage (0.50 V). This translates to a remarkable energy density of 2882.34 mWh/g (referenced against the standard hydrogen electrode potential), making it a strong contender for next-generation battery technologies. Furthermore, our investigation revealed rapid diffusion barriers for Mg-ion migration with exceptional properties with robust compatibility with electrolytes, makes it anode materials for Mg-ion batteries, attracting significant interest in the near future.

Silicene/BN heterostructure as high-performance anode material for Mg-ion batteries

Finding a suitable anode material is a key part of the development of Mg-ion batteries (MIBs) to commercialize. In this work, an outstanding Silicene/BN heterostructure was discovered as a candidate anode material for MIBs by using first-principles calculations. The mixed sp2/sp3 orbital hybridization of silicon atoms makes Silicene monolayer easy to adsorb Mg atoms. The introduction of BN monolayer can effectively buffer the structural deformation and improve the electrochemical performances. Compared to pristine Silicene, the Silicene/BN heterostructure exhibited higher structural stability and Mg adsorption capacity. The diffusion of Mg ions in the heterostructure interlayer was easier with a low barrier of 0.160 eV than that on the Silicene monolayer. A comparable low open circuit voltage (0.112 V) was also observed. These results indicated the potential of Silicene/BN heterostructure as a high-performance anode material for MIBs.

A novel two-dimensional monolayer MB4(M = Cr, Mo, W) MBenes as a high-performance anode material for Mg-ion batteries

Rechargeable magnesium-ion batteries have garnered with great interest because abundant resources of magnesium and their potential for achieving high energy density. However, the realization of MIBs is hindered by the lack of appropriate electrode materials. In this study, the potential of 2D monolayers of CrB4, MoB4, and WB4 as anode materials for MIBs has been thoroughly studied using DFT calculations. Our preliminary investigations indicate that these monolayers demonstrate structural, mechanical, and thermodynamic stability. The significantly negative adsorption energy plays a vital role in stabilizing the surface adsorption of Mg ions, preventing clustering, and ensuring the stability of MIBs. The maximum TSC values are 3377 mA h g−1,2311 mA h g−1 and 1416 mA h g−1; and relatively low average OCV of 0.27 V,0.28 V and 0.19 V for CrB4, MoB4 and WB4 respectively, which is favoring to attaining high energy-density. The electronic properties revealed that as the Mg ion concentration increased, the electrical conductivity of the materials improved while maintaining their metallic nature, even after adsorption. However, the energy barriers were slightly higher and consistent with those of many common materials used as 2D anodes. Anticipated light shading of CrB4, MoB4, and WB4 was predicted to identify novel anode materials for MIBs.

V4C3 MXene: a Type-II Nodal Line Semimetal with Potential as High-Performing Anode Material for Mg-Ion Battery.

We have used density functional theory simulations to explore the topological characteristics of a new MXene-like material, V4C3, and its oxide counterpart, assessing their potential as anode materials for Mg-ion batteries. Our research reveals that V4C3 monolayer is a topological type-II nodal line semimetal, protected by time reversal and spatial inversion symmetries. This type-II nodal line is marked by unique drumhead-like edge states that appear either inside or outside the loop circle, contingent upon the edge ending. Intriguingly, even with an increase in metallicity due to oxygen functionalization, the topological features of V4C3 remain intact. Consequently, the monolayer V4C3 has a topologically enhanced electrical conductivity that amplifies further upon oxygen functionalization. During the charging phase, a remarkable storage concentration led to a peak specific capacity of 894.73 mAh g-1 for V4C3, which only decreases to 789.33 mAh g-1 for V4C3O2. When compared to V2C, V4C3 displays a significantly lower specific capacity loss due to functionalization, demonstrating its superior electrochemical properties. Additionally, V4C3 and V4C3O2 exhibit moderate average open-circuit voltages (0.54 V for V4C3 and 0.58 V for V4C3O2) and energy barriers for intercalation migration (ranging between 0.29-0.63 eV), which are desirable for anode materials. Thus, our simulation results support V4C3 potential as an efficient anode material for Mg-ion batteries.

The feasibility of BeP2 monolayer as an anode material for Mg-ion batteries: A density functional theory study

Nowadays, as a practical approach to enhancing energy density of a metal ion battery, discovering efficient electrode materials is the foremost option. At the beginning and end of metal adsorption, BeP2 is inherently metallic and delivers favorable electrical conductivity. According to first-principles computations, BeP2 can be considered potentially suitable electrode materials for Mg-ion battery. Notably, fully magnesium phase Mg2BeP2 for BeP2 offers a great theoretical capacity (578.35 mAh g−1) accompanied by single layer of Mg ions, which outperforms numerous formerly reported two-dimensional options. In the interim, it has been discovered that diffusion barrier and open-circuit voltage of BeP2, subsequent to complete adsorption of metal ions, exhibited an unexpectedly diminished value of 0.21 V. Contemporary research findings can facilitate discovery of innovative electrode materials of BeP2 classification catering to needs of metal ion batteries. It can be concluded that BeP2-based composites are promising anchor materials for advanced Mg-ion batteries.

A Novel Two-Dimensional TiClO as a High-Performance Anode Material for Mg-Ion Batteries: A First-Principles Study.

Searching for efficient electrode materials with excellent electrochemical performance is of great significance to the development of magnesium-ion batteries (MIBs). Two-dimensional Ti-based materials are appealing for use in MIBs due to their high cycling capability. On the basis of density functional theory (DFT) calculations, we comprehensively investigate a novel two-dimensional Ti-based material, namely, TiClO monolayer, as a promising anode for MIBs. Monolayer TiClO can be exfoliated from its experimentally known bulk crystal with a moderate cleavage energy of 1.13 J/m2. It exhibits intrinsically metallic properties with good energetical, dynamical, mechanical, and thermal stabilities. Remarkably, TiClO monolayer possesses an ultra-high storage capacity (1079 mA h g-1), a low energy barrier (0.41-0.68 eV), and a suitable average open-circuit voltage (0.96 V). The lattice expansion for the TiClO monolayer is slight (<4.3%) during the Mg-ion intercalation. Moreover, bilayer and trilayer TiClO can considerably enhance the Mg binding strength and maintain the quasi-one-dimensional diffusion feature compared with monolayer TiClO. All these properties indicate that TiClO monolayers can be utilized as high-performance anodes for MIBs.

Rational design of h‐AlC monolayer as anode material for Mg‐ion battery: A DFT study

AbstractIn the present work, we have analyzed the suitability of two‐dimensional (2D) h‐AlC as a high‐capacity anode material for Mg‐ion batteries (MIBs) by employing first principles‐based density functional theory (DFT). The structural parameters, electronic band structure, partial density of states (PDOS), theoretical storage capacity (TSC), diffusion energy barrier (DEB), open‐circuit voltage (OCV), and room temperature stability (from ab initio molecular dynamic (AIMD) simulations) are calculated and discussed. The band structure of h‐AlC monolayer remains metallic for all considered adsorption concentrations of Mg‐atoms which indicates its good electrical conductivity. A significant quantity of charge is transferred from Mg atom to h‐AlC during adsorption of the Mg atom due to its lower electronegativity compared with the Al and C atoms. The calculated TSC is 1221.75 mAh g−1 which is higher than many anode materials. For MIBs, calculated DEB and OCV are 1.21 and 0.73 V, respectively. However, transition from planar structure to buckled structure takes place during the adsorption of more than 9 Mg‐atoms over h‐AlC. The lattice change is negligible during adsorption of Mg atoms. The AIMD calculations revels that the 9 and 18 Mg atoms adsorbed h‐AlC is stable at T = 300 K. The aforementioned findings suggest that h‐AlC can be anode material for MIBs.

Two-dimensional B_2C as a potential anode material for Mg-ion batteries with extremely high theoretical capacity

The development of new high-capacity anode materials using ions other than lithium as a charge carrier is one of the essential strategies in searching for next-generation high-performance rechargeable batteries. Herein, using first-principles computations, we explore a B_2C monolayer as a potential anode material for Mg-ion batteries. The high stability of the free-standing B_2C monolayer has been demonstrated via calculating the adsorption energy, phonon dispersion, and ab-initio molecular dynamics simulations. The metallic character of the B_2C monolayer, desirable from the point of view of energy storage, ensures good electronic conductivity during the battery charge/discharge process. The calculated migration energy barrier, open-circuit voltage, and theoretical specific capacity of the B_2C monolayer are much better than those of some other two-dimensional materials. These findings provide the B_2C monolayer as a potential candidate for Mg-ion battery anode material with a high theoretical specific capacity of 3187.55 mAh/g.

Thermodynamic investigation of phase transformation in Sn anode for magnesium batteries

Metallic Mg anodes are incompatible with conventional electrolytes, such as Mg(BF4)2 or Mg(ClO4)2, due to the formation of a passivation layer that blocks the transport of Mg ions, thus limiting the selection of electrolytes and cathodes. Alloying anode materials for Mg batteries, such as Sn and its intermetallics, have recently been proposed as a new class of anode materials for Mg-ion batteries to address the issues of incompatibility with the conventional electrolytes. However, the large changes in the volume of the Mg–Sn alloy during cycling lead to poor Coulombic efficiency and rapid capacity degradation. The underlying reasons for how the structural changes hamper electrochemical performance remain unclear. In this work, we perform a theoretical study of the Mg–Sn alloys to have a deeper insight into the alloying process and the phase transformation in the Sn anode. This work is the first in-depth computational study that combines density functional theory and cluster expansion to investigate the phase transition process in the Mg–Sn system that includes Mg2Sn, α-Sn, and β-Sn structures. We considered three possible routes for the transformation pathway from Mg2Sn to β-Sn: Mg2Sn → α-Sn → β-Sn, Mg2Sn → β-Sn, and Mg2Sn → amorphous phase → β-Sn. Our study shows that the transformation of Sn between its α- and β-phases hinders the alloying process. This hindrance, together with the amorphization of the alloy, is revealed to be the key factor to understand the poor electrochemical performance of the Mg–Sn alloy.

First-principles investigations to evaluate Mo2B monolayers as promising two-dimensional anode materials for Mg-ion batteries

Magnesium-ion batteries have the potential to replace the current commercial Li-ion batteries due to their eco-friendliness and cost-effectiveness. However, because of the strong polarization of Mg ions, conventional electrode materials find it difficult to capture Mg ions. In order to find an excellent anode material for Mg-ion batteries, we used density functional theory to evaluate the applicability of T-type and H-type Mo2B monolayers as electrode materials for Mg-ion batteries. The simulation results show that the adsorption energies of T-type and H-type Mo2B monolayers for Mg atoms are −1.08 eV and −0.78 eV (−2.16 eV and −2.14 eV with the solvent effect), respectively, which are sufficient to ensure the stability of the procession of magnetization. In addition, the ultra-low diffusion barriers (0.057 eV/0.110 eV) of Mg atoms on their surfaces show a good charge and discharge rate. The theoretical specific capacity (529 mA h g−1) and the theoretical voltages (0.65 V/0.40 V) indicate that T-type and H-type Mo2B monolayers are promising anode materials for Mg-ion batteries.

One-Pot Super Critical Fluid Synthesis of Spinel MnFe2O4 Nanoparticles and its Application as Anode Material for Mg-ion Battery

In present study, the synthesis of spinel MnFe2O4 nanoparticles using a facile one-pot super critical fluid method and their application for Mg-ion battery application as anode materials is reported. The synthesized MnFe2O4 nanoparticles were well characterized for their structure and morphology using XRD, SEM, TEM and EDS analysis. The average particle size of materials was less than 50 nm with spinel structure. The main feature of magnesium ion battery is its high specific capacity and large volumetric energy density, which makes it a promising alternative to Li-ion batteries. The spinel MnFe2O4 material has been used as an anode material for Mg-ion batteries. At different C-rates (0.05C to 2C), electrochemical charge-discharge behaviour has been observed. In first cycle of the phase-pure spinel structured anode, an initial specific capacity of 195.82 mAh/g, 139.70 mAh/g, 25.04 mAh/g and 14.16 mAh/g were obtained at C rate of 0.05C, 0.1C, 1C and 2C, respectively. A possible phase conversion reaction of the anode resulted in a decrease in specific capacity with increasing C-rate.

Penta graphene: a superior anode material for Mg-ion batteries with high specific theoretical capacity

Penta graphene: a superior anode material for Mg-ion batteries with high specific theoretical capacity

A DFT-D guided surface engineering of 2-D functionalized graphyne analogue covalent triazine frameworks as a high-capacity anode material of Mg-ion battery

In the present study, we have explored the potential application of pure and functionalized 2-D graphyne-like covalent triazine framework (GYCTF) as an anode material for Mg-ion batteries, using dispersion-corrected DFT. The accurate interaction energies are crucial for energy storage and battery applications as they are directly related to the key properties in electrochemistry, such as storage capacities, in general, and open-circuit voltages (OCVs), in particular. We have found that Mg preferably adsorbs above the center of all carbon six-membered rings of GYCTF with adsorption energy of about 83.4 kcal mol−1. After functionalization, -SH increases the maximum coverage of Mg on surface from 4 to 9 Mg. Also, –CH3 strongly reduces the specific capacity of GYCTF in MIB application. After functionalization, -SH increases the maximum coverage of Mg on the surface from 4 to 9 Mg. Also, –CH3 strongly reduces the specific capacity of GYCTF in MIB application. The single-layer GYCTF-SH can be magnesiated on both sides yielding Mg9C13N3S4H4 with a storage capacity as high as 1462.4 mAh g−1 with an average OCV of 0.68 V. Our findings show better results in terms of storage capacity, negligible volume expansion, low OCV, and low diffusion energies comparing with commonly studied 2-D materials, making thiol-functionalized GYCTF a promising candidate as an anode material for Mg- ion batteries.

Hexa-cata-hexabenzocoronene nanographene as a promising anode material for Mg-ion batteries.

We investigated the possible use of a hexa-cata-hexabenzocoronene nanographene (HCHN) as an anode material for Mg-ion batteries (MIBs) implementing the B3LYP-gCP-D3/6-31G* scheme. The Mg cation or atom is adsorbed on the HCHN with the adsorption energy of - 200.3 or - 4.7kcal/mol. The energy barrier related to transferring Mg cation on the HCHN surface was calculated to be 7.5kcal/mol, producing the diffusion coefficient of 1.90 × 10-8cm2/s. It shows that the ion mobility is high and the rate of charge or discharge is fast. The calculated specific storage capacity of HCHN is 589.4mAh/g and the great cell voltage is 4.23V that is generated by the interaction of cation-π between Mg2+ and HCHN, which is strong. The HCHN is considered an ideal candidate to be used as an anode material in MIBs since its storage capacity and ion mobility are high, and it has a large cell voltage.

Theoretical investigation of the intercalation mechanism of VS2/MXene heterostructures as anode materials for metal-ion batteries

Ti2CO2 is one of the lightest MXenes, which is beneficial for achieving higher capacity as electrode material for batteries. However, its semiconductor conductivity has a negative effect on its charging/discharging rate and cyclability performance as electrode materials for batteries. Integrating two different two-dimensional materials to form heterostructures is an effective strategy to optimize the properties of materials. In this work, two heterostructures VS2/Ti2CT2 (T = O and S) are constructed and their electrochemical performances as anode materials for Li, Na and Mg-ion batteries are explored based on first-principles calculations. First of all, the lattice mismatch of these two heterostructures are relatively small, particularly, the lattice mismatch of VS2/Ti2CS2 is as low as 0.63%. Besides, compared with common graphene/Ti2CO2 and MoS2/Ti2CO2 heterostructures, VS2/Ti2CT2 simultaneously exhibit superior metal conductivities and stronger adsorption properties towards Li, Na and Mg atoms, thus achieving higher capacities. Considering the strong adsorption properties, suitable diffusion energy barriers, low open circuit voltages and high capacities, VS2/Ti2CO2 and VS2/Ti2CS2 are proposed to be promising high-performance anode materials for Mg-ion batteries, and VS2/Ti2CS2 is a preferable anode material for Na-ion batteries.

Zigzag and armchair AlN nanotubes as anode materials for Mg-ion batteries: Computational study

We studied the potential application of a zigzag and an armchair AlN nanotube (AlNNT) as an anode material for the Mg-ion batteries (MIBs) using B3LYP-gCP-D3/6-31G* model chemistry. The Mg2+ adsorption energy on the zigzag or armchair AlNNTs is −217.2 or −234.9 kcal/mol, but the Mg atom interaction is much weaker and the adsorption energy is −10.5 or −5.3 kcal/mol. The dispersion term is much more important for the Mg interaction compared to the Mg2+. This term includes 68.6% of the Mg atom adsorption energy on the zigzag tube while its contribution for Mg cation adsorption is about 3.8%. The maximum energy barrier for an Mg2+ migration and cell voltage are 6.1 kcal/mol and 4.47 V for zigzag and 5.3 kcal/mol and 4.95 V for armchair AlNNT, respectively. Thus, the AlNNTs provide a great ion mobility leading to a faster charge/discharge rate because of small energy barriers. The larger cell voltage, and higher ion mobility suggest the armchair AlNNTs as a plausible anode material for application in the anode of MIBs, compared to the zigzag AlNNT. The effect of Mg/Mg2+ adsorption on the electronic properties of AlNNTs is also discussed.

Magnesiation of bare and halides encapsulated B40 fullerenes for their potential application as promising anode materials for Mg-ion batteries

Density functional theory (DFT) calculations using the PBE0-D3 functional and the 6–31 + G(d) basis set were carried out to determine the potential application of newly experimentally observed B40 fullerene for the anode electrode for Mg-ion batteries (MIBs). Calculated results suggest the bare B40 fullerene as a promising anode material with remarkable average open-circuit voltage of 5.5 V and storage capacity of 744 mAhg−1. Furthermore, it was found that the halides (F–, Cl–, and Br–) encapsulation inside B40 fullerene with both remarkable thermodynamic and kinetic stability can markedly enhance average open-circuit voltage up to 8.8 V. This value is remarkable compared with previous reports in the literature. Additionally, we re-calculated the average open-circuit voltage with the TPPSh, M06-2X, and B3LYP-D3 functionals along with the 6–311 + G(d) basis set. The results are similar to those values obtained at PBE0-D3/6–31 + G(d). The nature of Mg and Mg2+ interaction with bare and halides encapsulated B40 were also analyzed through the quantum theory of atoms in molecules (QTAM). The current results in this study might open new windows for the design of promising boron-based anode materials for MIBs.

A First-Principles Study of MBene as Anode Material for Mg-Ion Battery

Abstract Developing novel nanostructured anode materials for Mg storage plays an important role in improving the performance of magnesium-ion (Mg-ion) batteries. Two-dimensional (2D) metal borides (MBenes) are evaluated as potential anode materials in the present study. Simulation results demonstrate that Cr2B2 is a competitive anode material, which can deliver a maximum theoretical capacity of 853.4 mAh/g with an average open-circuit potential of 0.53 eV versus Mg2+/Mg. In addition, Cr2B2 as anode also can exhibit superior diffusion kinetics due to a low energy barrier of 0.38 eV. Comparing with Cr2B2, Mo2B2 exhibits less but still high Mg storage capacity, with a maximum capacity of 502.1 mAh/g. In addition, Mg diffusion barrier on Mo2B2 is 0.84 eV and the average open-circuit potential is 0.67 V versus Mg2+/Mg, both of which are still comparable to the reported anode materials for Mg-ion batteries.

Graphyne as an anode material for Mg-ion batteries: A computational study

Abstract Although Li-ion batteries have different advantages, they suffer from short lifetime, high cost, and safety problems. The wide availability, multivalent character, and nontoxicity of magnesium suggest Mg-ion batteries (MIBs) as an alternative to Li-ion batteries. Here, we investigated the potential application of graphyne (as an alternative material to graphene) in the anode of MIBs at B3LYP and B3LYP-gCP-D3 levels. The adsorption energies of Mg and Mg2+ on graphyne were observed to be −6.1 and −223.6 kcal/mol, respectively. The dispersion term was predicted to be much more important for the Mg atom adsorption compared to the Mg2+ cation. The maximum energy barrier for the migration of Mg and Mg2+ over the graphyne surface was about 10.6 and 5.2 kcal/mol, respectively. The calculated cell voltage and specific storage capacity for graphyne respectively were 4.69 V and 558 mAh/g. The high cell voltage of MIBs is mostly attributed to the multivalent character of Mg atoms and strong cation–π interactions. Based on the results, the combination of high cell voltage, ultrahigh storage capacity, and good Mg mobility suggests graphyne as a promising anode substance in MIBs.

Atomistic Mechanisms of Mg Insertion Reactions in Group XIV Anodes for Mg-Ion Batteries.

Magnesium (Mg) metal has been widely explored as an anode material for Mg-ion batteries (MIBs) owing to its large specific capacity and dendrite-free operation. However, critical challenges, such as the formation of passivation layers during battery operation and anode-electrolyte-cathode incompatibilities, limit the practical application of Mg-metal anodes for MIBs. Motivated by the promise of group XIV elements (namely, Si, Ge, and Sn) as anodes for lithium- and sodium-ion batteries, here, we conduct systematic first-principles calculations to explore the thermodynamics and kinetics of group XIV anodes for MIBs and to identify the atomistic mechanisms of the electrochemical insertion reactions of Mg ions. We confirm the formation of amorphous Mg xX phases (where X = Si, Ge, and Sn) in anodes via the breaking of the stronger X-X bonding network replaced by weaker Mg-X bonding. Mg ions have higher diffusivities in Ge and Sn anodes than in Si, resulting from weaker Ge-Ge and Sn-Sn bonding networks. In addition, we identify thermodynamic instabilities of Mg xX that require a small overpotential to avoid aggregation (plating) of Mg at anode/electrolyte interfaces. Such comprehensive first-principles calculations demonstrate that amorphous Ge and crystalline Sn can be potentially effective anodes for practical applications in MIBs.