Ultrasounds-assisted solvothermal synthesis of Ni-Co-Mn MOFs/PANI-CNTs nanocomposites with enhanced electrochemical energy storage performance

Abstract

Among various energy storage devices, one of the emerging classes to be considered nowadays is advanced eco-friendly supercapacitors. Despite vast research regarding their electrochemical performance, there is still room for further refinement. Here, such an attempt has been made by producing nanocomposites of NiCoMn ternary transition metal-organic frameworks (MOFs) with conductive-natured carbon nanotubes (CNTs) functionalized with polyaniline (PANI). A rather different approach i.e., ultrasounds assisted solvothermal method has been employed to prepare the MOFs and their nanocomposites with varying concentrations (0, 20, 40, 60 mg) of PANI functionalized CNTs (PC). A comparison analysis suggests that NiCoMn/PC-40 (40 mg PANI-CNTs) has shown excellent electrochemical performance. In the material of worth attention, the formation of flower-like morphology and crystallinity was explored and confirmed by SEM and XRD characterizations. FT-IR analysis facilitated the exploration of compositional and functional groups of the best-performing material. The large cyclic area, highest specific capacity, excellent stability, less ion transport resistance, and excellent morphology proved NiCoMn/PC-40 as an excellent next-generation supercapacitor battery-grade material with the dominance of diffusive response (71.7%). It has been shown 1194 C/g of specific capacity with an extraordinary energy density of 82 Wh/kg and 1105 W/kg of power density by the NiCoMn/PC-40. At 20 A/g, 100% cyclic stability after 5000 charge/discharge cycles with 97.5% columbic efficiency was achieved. In essence, the excellent electrochemical performance, ease of fabrication, and affordable cost can provide a breakthrough in value addition of NiCoMn/PC-40 worth as a proficient energy storage material.