ABSTRACT
The search for low-diffusion barriers and high-capacity anode materials is considered a key step in boosting the efficiency of metal-ion batteries. Herein, we investigate the impact of a series of conducting polymers (CPs), namely, polyacetylene (PA), polypyrrole (PP), poly-p-phenylene (PPPh), and polythiophene (PT), on enhancing the material design and anodic performance of boron nitride nanosheet (BNNS)-based Li-ion and Na-ion batteries. For this purpose, first principle DFT simulations, utilizing both clustered and periodic models, are systematically performed to assess the stability of such nanostructures and their electronic behavior as potential anodic materials. It is revealed that frontier molecular orbitals calculated for BNNSs are stabilized upon association with the series of CPs, resulting in a reduction in the energy gaps of CP-BNNSs by nearly 50%, which in turn improves the charge transfer properties and cell reaction kinetics. A remarkable improvement in the cell voltage is predicted for PP and PT functionalized BNNSs, reaching approximately 3.5 V for Li+ and 3.0 V for Na+ ions. The outcome of the study emphasizes the influence of the size of metal ions, whether mono- or di-valent, and the nature of adsorbed conducting polymers. Manipulating the electronic features of boron nitride nanostructured surfaces through non-covalent functionalization with conducting polymers could pave the way for the design of highly efficient energy storage anodic CP-BNNS-based systems.
ABSTRACT
Advanced battery materials are urgently desirable to meet the rapidly growing demand for portable electronics and power. The development of a high-energy-density anode is essential for the practical application of B3+ batteries as an alternative to Li-ion batteries. Herein, we have investigated the performance of B3+ on monolayer (MG), bilayer (BG), trilayer (TG), and tetralayer (TTG) graphene sheets using first-principles calculations. The findings reveal significant stabilization of the HOMO and the LUMO frontier orbitals of the graphene sheets upon adsorption of B3+ by shifting the energies from -5.085 and -2.242 eV in MG to -20.08 and -19.84 eV in 2B3+@TTG. Similarly, increasing the layers to tetralayer graphitic carbon B3+@TTG_asym and B3+@TTG_sym produced the most favorable and deeper van der Waals interactions. The cell voltages obtained were considerably enhanced, and B3+/B@TTG showed the highest cell voltage of 16.5 V. Our results suggest a novel avenue to engineer graphene anode performance by increasing the number of graphene layers.
ABSTRACT
Lithium-ion batteries (LIBs) have displayed superior performance compared to other types of rechargeable batteries. However, the depleting lithium mineral reserve might be the most discouraging setback for the LIBs technological advancements. Alternative materials are thus desirable to salvage these limitations. Herein, we have investigated using first-principles DFT simulations the role of polypyrrole, PP functionalization in improving the anodic performance of boron nitride nanosheet, BNNS-based lithium-ion batteries and extended the same to sodium, beryllium, and magnesium ion batteries. The HOMO-LUMO energy states were stabilized by the PP functional unit, resulting in a significantly reduced energy gap of the BNNS by 45%, improved electronic properties, and cell reaction kinetics. The cell voltage, ΔEcell was predicted to improve upon functionalization with PP, especially for Li-ion (from 1.55 to 2.06 V) and Na-ion (from 1.03 to 1.37 V), the trend of which revealed the influence of the size and the charge on the metal ions in promoting the energy efficiency of the batteries. The present study provides an insight into the role of conducting polymers in improving the energy efficiency of metal-ion batteries and could pave the way for the effective design of highly efficient energy storage materials.
