Advancements in energy storage: Combining hollow iron cobalt selenide spheres with nickel cobalt layered double hydroxide nanosheets

Metal selenides with high conductivity are emerging as potential candidates for electrode materials in the realm of supercapacitors. In this context, we introduce the FeCoSe2@NiCoLDH hollow sphere, termed FCS@NCLDHHS, crafted using a straightforward solvothermal method. This sphere is structured by layering two-dimensional NiCoLDH nanosheets onto FeCoSe2 hollow spheres. Merging NiCoLDH with FeCoSe2 results in heterostructures that significantly enhance supercapacitive behavior. Moreover, the external NiCoLDH nanosheets play a pivotal role in preventing the corrosion and degradation of the FeCoSe2 hollow structure during extended stability evaluations. Owing to these advantages, the FCS@NCLDHHS electrode showcases impressive metrics: a specific capacity of 1305C g-1, rate performance of 80.25 % at 25 A g-1, and cyclic longevity retaining 94.45 % capacity. Furthermore, a device ((-)activated carbon (AC)//(+)FCS@NCLDHHS), constructed using FCS@NCLDHHS (cathode) and AC (anode) delivers an energy density (ED) of 55.45 W h k-1 at a power density (PD) of 803.65 W kg -1 and maintains 88.25 % of its original capacity. This research potentially paves the way for merging two efficient materials to create a multifaceted hollow structure with enhanced electrochemical attributes.