Rational design of ternary NiCo2Alx-LDH coupled with PANI coated Nitrogen-doped carbon capsule for High-Performance asymmetric supercapacitors

Abstract

This paper designs and produces ternary NiCo2Alx-LDH grown directly on a novel porous hollow structure of nitrogen-doped carbon capsule (N-Cc) conducting matrix with a PANI coating layer. The carefully designed NiCo2Alx-LDH/N-Cc@PANI electrodes exhibit electrochemical properties that are highly prized for their energy storage utility: specifically, a gravimetric capacitance of 1630F/g, an energy density of 55.75 Wh kg−1 at the power density of 750 W kg−1, and cyclic stability that achieves capacitance retention of 93.1 % after 5000 uninterrupted charge–discharge cycles. It should be noted that the electrode's excellent storage performance benefitted from the use of Al, which was crucial in stabilizing the LDH structure. It should also be pointed out that the 3D interconnected porous structure composed of N-Cc provides a greater accessible surface area and shortens the ion/electron transport distance, whilst PANI ensuring the LDHs remain firmly in contact with the conductive substrate.