Ternary nanocomposite cathodes based on 3D graphene-Ag nanoparticle-polyaniline for hybrid electrochemical energy device

Abstract

A ternary nanocomposite of three-dimensional graphene-silver nanoparticles-polyaniline (3DG-nAg-PANi) is prepared via an in-situ polymerization technique. The structural and morphological characterizations through X-ray diffraction, Fourier transform infrared, Raman spectroscopy and Field emission scanning electron microscopy confirmed the high purity 3DG-nAg-PANi nanocomposite. The prepared 3DG-nAg-PANi nanocomposite is used as a positive electrode with activated carbon as a negative electrode to fabricated asymmetric supercapacitor (ASC). The electrochemical performance studies revealed the outstanding performance of 3DG-nAg-PANi nanocomposite compared to its counterparts (3DG, PANi and 3DG-PANi). The maximum specific capacity is found for 3DG-nAg-PANi ternary nanocomposite (115.6 C g−1) compared with 3DG (71.6 C g−1), PANi (32.2 C g−1), and 3DG-PANi nanocomposite (47.2 C g−1), at a current density of 1 A g−1 in the standard three-electrode cell. The assembled ASC delivered maximum specific energy of 11.67 Wh kg−1 at a specific power of 300 Wkg−1 using 0.4 A g−1 of current density. The ASC is able to retain 92% of initial capacity after 5000 cycles at a current density of 2 A g−1. The electrochemical performance of the 3DG-nAg-PANi ternary nanocomposite reveals that it is a suitable candidate for electrodes in the energy storage systems.