One-Step Growth of NiCoAl Layered Double Hydroxides Microsphere toward High Energy Density Supercapacitor

Abstract Layered double hydroxides (LDHs) are a class of 2D structure anionic clays with tunable structure, which has high theoretic faradaic capacitance. However, self-aggregation of LDHs nanosheet usually restricts their energy storage performances. Microspheres materials possess high specific surface area and structure stability, which provide a promising method to address the issue of aggregation in LDHs nanosheet. In this work, we present the one-step fabrication of NiCoAl-LDH microspheres with well-dispersed morphology and high electrochemically active surface area. The fabricated Ni1Co2Al1-LDH microspheres present specific capacitance of 451 F g‒1 at current density of 5 A g‒1, which is 1.92 times higher than that of conventional lamellar Ni1Co2Al1-LDH. Based on the Ni1Co2Al1-LDH microspheres, an all-solid-state asymmetric supercapacitor device was fabricated, giving high energy density, power density and long term cycling stability. This one-step growth of NiCoAl-LDH microspheres method has potential applications in large-scale manufacture of energy storage materials.