Development of electrocatalysts with reduced noble metal content with enhanced catalytic performance has been of importance in cost-effective design of renewable energy conversion devices. The design of core-shell nanoparticles as electrocatalysts represents a promising approach for preparing not only limiting the use of expensive precious metals also developing catalytic activity. Herein, simple one-pot synthetic route to fabricate anisotropic hexagonal-shaped core-shell nanosandwich structures with binary and ternary composition will be reported. Also, the core composition of hexagonal nanosandwich structures is easily controllable by modulating the amount of precursor. The hexagonal core-shell nanosandwich possesses enhanced electrocatalytic activity toward oxygen evolution reaction (OER), with their OER activity being dependent on their core compositions.