Synthesis and electrochemical energy storage performance evaluation of PANI functionalized CNTs/Ni–Zn (PO4)2 nanocomposites

In this study, the nanocomposites of binary transition metal phosphate [Ni 0.75 Zn 0.25 (PO 4 ) 2 ] with PANI–CNTs were prepared through sonochemical-assisted synthesis approach and were characterized for their potential use in electrochemical energy storage applications. The morphology and hierarchical structure were seen by scanning electron microscopy (SEM) coupled with EDX mapping, whereas the chemical composition and functional group analysis were done by EDX, XRD, and FT-IR. At 0.7 Ag −1 current density, the best-performing electrode of Ni 0.75 Zn 0.25 (PO 4 ) 2 –60 mg PANI/CNTs (NZP60) showed specific capacity of 1143 Cg −1 . A representative asymmetric supercapacitor (ASC) device of NZP60//AC showed an exceptional energy density of 89.2 Wh kg −1 at 630 W kg −1 power density. Additionally, the cyclic performance (99.86% after 5000 GCD cycles) and rate performance (25% increase after stability test) were excellent. The ASC device has dominant diffusive behavior (89.7%) due to its highest pseudocapacitive binary metal phosphate chemically grafted on conductive polyaniline and carbon nanotubes (CNTs). Hence, Ni–Zn binary metal phosphate/PANI functionalized CNTs nanocomposites have good potential to be used in ASC-based energy storage applications.