Design of an Efficient Supercapacitor Binder-Free Electrode Using a Two-Step In-Situ Hydrothermal Synthesis of Hierarchical Ni-Co LDH/Ni₂SnO₄ Nanosheets Stacks on Ni Foam

Improving the electrochemical performance of electrode materials via structural design is critical in developing energy storage technologies. In this investigation, a nanoarray electrode composed of Co-Ni layered double hydroxide (Ni-Co LDH) nanosheets and Ni2SnO4 nanosheets (Ni2SnO4 NSs) stabilized on Ni foam (NF) is developed utilizing an in-situ growth method to its electrochemical properties in supercapacitors can be evaluated. The Ni2SnO4 was created in the first stage using a light hydrothermal reaction as the core. The Ni-Co LDH was then hydrothermally immobilized using the electrode, which had been made as a skeleton. The structural and textural study of the material was described using energy dispersive X-ray analysis (XRD), Fourier transforms infrared (FT-IR), field-emission scanning electron microscopy, and transmission electron microscopy. When the developed Ni-Co LDH/Ni2SnO4/NF electrode is compared to the Ni2SnO4/NF electrode, the electrochemical result shows a specific capacitance of up to 3,924 F g(-1) at 1 A g(-1) in a 2 mol L-1 KOH electrolyte, as well as a capacitance retention of 95% after 3000 cycles. Unsymmetrical supercapacitors made of Ni-Co LDH/Ni2SnO4/NF and activated carbon demonstrated exceptional electrochemical properties, including high rate capability, high energy, and power density (91.03 Wh kg(-1) and 9.0 kW kg(-1), respectively), and long cycle life. Due to its unique core/shell structural system, which facilitates ion diffusion and offers a fast electron transport kinetic model and good strain lodging, the rising pseudocapacitive behaviors render it an intriguing candidate for electrochemical energy storage.