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Destiny functional theory (DFT) calculations are undertaken in order to scrutinize the electrochemical and calcium (Ca) storage characteristics of a graphyne-like aluminum nitride monolayer (G-AlNyen) as an electrode material for Ca-ion batteries (CIBs). The results show that the change in internal energy as well as the cell voltage values for the CIB with the G-AlNyen anode are comparable to others with two-dimensional 2D nano-materials. It is shown that Ca is adsorbed primarily onto the center of a hexagonal and triangular ring of G-AlNyen with absorption energies of −2.06 and −0.42 eV. After increasing the concentration of Ca atoms on G-AlNyen, the adsorption energy as well as the cell voltage decreases. Lower values of 0.15–0.32 eV related to the diffusion barrier confirm that the diffusion of Ca in the 2D nano-sheets is rapid. G-AlNyen shows a maximum theoretical capacity of approximately 869.23 mAh h g−1. The results are evaluated in terms of charge transfer, structure, energy as well as electronic characteristics and provide insight into the construction of better anode materials with higher capacity for the CIB. • G-AlNyen@Ca has changed his semiconductor character to metallic character. • Investigation of the adsorption and charge transfer of Ca on the G-AlNyen. • The diffusion energy of Ca, suggesting fast charging/discharging processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Investigating Ca storage mechanism and properties of BeP 2 was calculated. • Ca has low diffusion barrier and high capacity on BeP 2 surface. • The interface electronic behavior of BeP 2 enhance the adsorption of Ca. One of the efficient methods for boosting the energy density of modern metal-ion batteries is finding electrode materials with high performance. Before and following the adhesion of metal ions, a BeP 2 monolayer (BeP 2 ML) has intrinsic metallicity and high conductance. The first-principles DFT computations demonstrate that BeP 2 ML is one of the encouraging electrode materials for Ca-ion batteries (CIBs). Furthermore, the theoretical capacity of a fully Ca phase Ca 2 BeP 2 for BeP 2 ML was high (629 mA h g−1) having an additional calcium ion layer, which outperformed other two-dimensional ones reported in the literature. Additionally, after the full adhesion of metal ions, BeP 2 ML exhibited a surprisingly low open circuit voltage and diffusion barrier (0.24 V). The present piece of research can provide insights into exploring new BeP 2 ML-type electrode materials for CIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] Presently, great attention is being paid to the search for promising anode materials for metal-ion batteries (MIBs) due to the rapid evolution of numerous modern electronic gadgets. In this investigation, we have predicted for the first time that the buckled-hexagonal Nb 2 S 2 monolayer which may be an efficient anode material for calcium-ion batteries (CIBs). To that objective, we have explored the pristine monolayer system's energetical, dynamical, and thermal stability. The inherent metallicity of the pristine monolayer facilitates its electrical conductivity as an electrode material. Our study also reveals the structural and electrical properties of the Ca-adsorbed Nb 2 S 2 monolayer. It is observed that Ca-atoms prefer to get intercalated on top of the buckled hexagon of the pristine monolayer, and the metallicity of the 2D nanosheet remains preserved. In the adsorption process, Bader charge analysis is used to determine the amount of charge transfer from the Ca atom to the Nb 2 S 2 monolayer. Furthermore, this system exhibits a high storage capacity of 1288.86 mAh/g and a moderately low diffusion energy barrier of 0.76 eV. The calculated open-circuit voltage of 0.49 V and the other results suggest that the Nb 2 S 2 monolayer may be a potential candidate for anode material for rechargeable Ca-ion batteries. [ABSTRACT FROM AUTHOR]

Because of cost-effective production and abundant resources of calcium, Ca-ion batteries (CIBs) are an appropriate option to alternate Li-ion batteries (LIBs). A new category of anode materials for CIBs has emerged since the successful synthesis of carbon nanotubes, which are B and N doped derivatives of it. For high-performance CIBs, BC 2 N nanotube (BC 2 NNT) has been studied as promising anode materials. In order to comprehend electrochemical attributes, cycling stability, and adsorption behavior of BC 2 NNT, first-principles computations have been executed. Based on nuclear magnetic resonance computations, two types of hexagonal rings (B 2 C 2 N 2 (I) and BC 4 N (II)) were specified that are non-aromatic. Ca has adsorption on B 2 C 2 N 2 and BC 4 N with adsorption energy (E ad) values of −47.44 and −28.50 kcal/mol, respectively. Specific capacity value has been determined to be as high as 840 mAh/g. The predicted average open-circuit voltage (OCV) for BC 2 NNT is 1.56 V, which has a larger value than that of other 2D materials. All mentioned reasons provide BC 2 NNT as an acceptable anode material for use in CIBs. In present research, results may create new ways of designing favorable boron-carbon-nitrogen based anode materials for CIBs. • DFT calculations have been performed for understanding the anodic properties of BC 2 NNTs for CIBs. • Mg preferably adsorbs on nearly B atom with E ad −47.44 kcal/mol. • The diffusion barriers have low values (0.11 eV), indicating that the MIBs in the BC 2 NNTs. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations are used to investigate the basic electrochemical characteristics of Si-based anodes in calcium ion batteries (CIBs). The calculated average voltage of Ca alloying with fcc-Si to form the intermetallic Ca x Si phases (0.5 < x ≤ 2) is of 0.4 V, with a volume variation of 306%. Decalciation of the lower Ca content phase, CaSi 2 , is predicted at an average voltage between 0.57 V (formation of Si-fcc, 65% volume variation) and 1.2 V (formation of metastable deinserted-Si phase, 29% volume variation). Experiments carried out in conventional alkyl carbonate electrolytes show evidence that electrochemical “decalciation” of CaSi 2 is possible at moderate temperatures. The decalciation of CaSi 2 is confirmed by different characterization techniques. [ABSTRACT FROM AUTHOR]