Electrochemical properties of high-power supercapacitors using ordered NiO coated Si nanowire array electrodes

Abstract

Highly ordered NiO coated Si nanowire arrays are fabricated as electrode materials for electrochemical supercapacitors (ES) via depositing Ni on electroless-etched Si nanowires and subsequently annealing. The electrochemical tests reveal that the constructed electrode has superior electrical conductibility and more active sites per unit area for chemical reaction processes, thereby possessing good cycle stability, high specific capacity, and low internal resistance. The specific capacity is up to 787.5 F g−1 at a discharge current of 2.5 mA and decreases slightly with 4.039% loss after 500 cycles, while the equivalent internal resistance is ∼3.067 Ω. Owing to its favorable electrochemical performance, this ordered hybrid array nanostructure is a promising electrode material in future commercial ES.