Among various semiconductors, silicon (Si) is one of the promising materials for li-ion battery due to abundant availability, cost- effective and high theoretical storage capacity, etc. Due to its greater specific capacity (4200 mAh g^-1, Li4.4Si), low cost, low working potential, and environmental friendliness makes it as most interesting storage semiconducting material. Number of studies have been conducted in the field of silicon and silicon- carbon based composite anode materials. Studies revealed that Si based anode, has several drawbacks, including a low initial Coulombic efficiency (ICE) (25–70% depending on Si composition and structure) and extremely high-volume expansion (300–400% depending on Si composition and structure) of Si particles during charging and discharging phenomena. Researchers have partially prevented Si expansion difficulties by using Si nanostructures such as nanoparticles, nanorods, and nanowires. However, in the presence of the electrolyte, nano-Si with a high surface area to volume ratio is extremely reactive, resulting in electrolyte deterioration during cycling. Physical and chemical vapor deposition processes are often used to attain silicon. It is usual to utilize thermal, microwave, or plasma aided breakdown of silicon precursors such SiH₄. Although widely used in the electronics sector, these approaches are not commercially feasible for secondary battery energy storage systems.

In keeping with this objective of identifying a cost-effective solution to amorphous Si production, electrodeposition or electrochemical impedance spectroscopy is a straightforward and low-cost technology that is widely employed on a broad scale. Furthermore, the approach has been widely employed in industrial applications, such as plating operations, to change the surface characteristics of metals and alloys to increase corrosion resistance while still providing an attractive finish. Several attempts to create silicon nanoparticles on metallic substrates by electrodeposition have already been made.

In this study, we provide an impedance-assisted new electrochemical approach that was used to create Si nanoparticles on a Cu substrate. The use of fixed potentials (-1.2 V vs pt) in the presence of varied frequency ranges (1 MHz to 0.1 Hz) result in the formation of Si nanoparticles. The relationship between the frequency boundary and the structural, morphological, and electrochemical behavior of Si nanoparticles has been investigated. The Si electrode's battery performance gives a discharge and charge capacity of 2200 and 1210 mAhg^-1 at a current rate of 2 Ag^-1 respectively. In compared to traditionally electrodeposited materials, the Si nanoparticles created in this work had a higher specific capacity.

Conclusion

When compared to other standard electrodeposition techniques (such as potentiostatic and galvanostatic), the Si nanoparticles produced by this approach performs better in terms of efficiency. For the invention of Si nanoparticles from a non-aqueous solution, a unique electrodeposition approach influenced by impedance modulation was used. A capacitive loop characterizes Nyquist diagrams of EIS data for Si deposition. Si electrode delivers the discharge and charge capacity were 2200 mAh/g and 1210 mAh/g at current density of 2 A/g. The existence of the low capacitance loop was related with good deposit morphology, but the inclusion of an extra reaction mechanism element in the EIS plot was associated with deteriorated deposit morphology. EIS may be used to forecast the final deposit morphology across a wide variety of electrolyte conditions.