Quantum capacitances of alkaline-earth metals: Be, Ca, and Mg integrated on Al12N12 and Al12P12 nanostructured—insight from DFT approach

摘要

Abstract In this study, the quantum capacitance (CQ) of aluminum nitride (Al12N12) and aluminum phosphide (Al12P12) have been investigated to explore the effects of Be, Ca, and Mg alkali-earth metals doping on the electronic properties, structural ability, and quantum capacitance of Al12N12@Be, Al12N12@Mg, Al12N12@Ca, Al12P12@Be, Al12P12@Mg, and Al12P12@Ca nanostructured using density functional theory (DFT) computation at the ωB97XD/6-311+G(d, p) level of theory. Detailed investigation into the electronic properties showed that Al12N12@Be and Al12P12@Be with value 6.95 and 6.17?eV possessed greater energy gap. Al12N12@Be and Al12P12@Ca possessed higher second-order stabilization energy with values 245.15 and 372.9?kJ/mol, respectively. Investigation into the quantum capacitance showed the maximum quantum capacitance with respect to Al12N12 surface is observed in Al12N12@Be with CQ value of 193.20 μF/cm2, and with respect to Al12N12, it is observed in Al12P12@Ca with CQ value of 107.14 μF/cm2. The trend of results obtained, can be seen to provide an effective and simple new idea for the design of Al12N12 and Al12P12-based supercapacitors that possess high energy density and storage ability.Graphical abstract