Directly grown Sr–Co layered double hydroxide (LDH) entangled two dimensional nanosheet film with superior performances

Designing of electrode with electrochemically rich structure, outstanding mechanical robustness and high electrical conductivity remains a challenge. We report a design of entangled Sr–Co Layered double hydroxides (LDHs) two-dimensional structure for such electrode. The hierarchical electrode with entangled nanosheet exhibit high specific capacitance of 1415 F g-1 at 5 A g-1 current density, excellent rate capability, high energy (12.28Whkg−1) and power density (567.788 W kg-1) and outstanding stability (80% capacity retention over 5000 cycles). The asymmetric device cell of Sr–Co LDH/ACC gives high energy density (27.78 Whkg-1) and power density (499.96Wkg-1) with cyclic performance of 1000 cycles with 95.24% capacitance retention. Further, we provide a detailed analysis of the various electrolyte environment experienced by the electrode and their effect on electrochemical properties. We pick out three different electrolytes; LiOH, NaOH, KOH and show that both selected electrolyte and metal combination for LDHs paves the way for outstanding electrochemical performance.