The new insight of superconductivity and supercapacitance applicability of Ni3Si: An ab initio exploration

In recent years, M${}_3$Si bulk materials have attracted considerable attention for their potential in energy storage technologies. This work focuses on exploring the superconducting and supercapacitance properties of Ni${}_3$Si using density functional theory with a generalized gradient approximation approach. The critical temperature of Ni${}_3$Si was determined to be 8.04 K, corresponding to a logarithmic average phonon frequency of 167.48 K. Analysis of the electronic density of states (DOS) revealed metallic characteristics, including a pronounced valley near the Fermi level, attributed to the limited contributions of the $3s$ and $3p$ orbitals of Si and the $4s$ orbital of Ni. Furthermore, the material demonstrated exceptional areal quantum capacitance, reaching a peak value of 1003.97 $\mu$F/cm${}^2$ at -1 V. The $3d$ orbitals of Ni atoms were identified as the primary contributors, accounting for approximately 293.78 $\mu$F/cm${}^2$ at the same voltage. These findings highlight Ni${}_3$Si as a promising candidate for both superconducting applications and as an electrode material in advanced supercapacitor devices.