DNA-mediated sonochemical synthesis and characterization of octahedron-like bismuth molybdate as an active electrode material for supercapacitors

Abstract

This endeavour reports on octahedron-like bismuth molybdate materials for supercapacitor electrodes as prepared via a facile Deoxyribonucleic acid (DNA)-mediated sonochemical method. The appropriate field emission scanning electron microscopic (FE-SEM) and high resolution transmission electron microscopic (HR-TEM) analyses have revealed that these freshly prepared bismuth molybdates possess octahedron-like morphologies. The shape and size of bismuth molybdate material were controlled more readily by DNA template so as to form an octahedron shape whereas aggregated morphologies are formed in the case of samples obtained without DNA mediation. The occurrence of probable functional groups and existence of individual constituents in all the above specimens of bismuth molybdate were identified through confocal Raman spectroscopy while their crystalline nature was confirmed through X-ray diffraction (XRD) studies. The electrochemical property of such bismuth molybdates was examined using cyclic voltammetric (CV) and chronopotentiometric (CP) methods. The fact that CV and CP curves observed in the case of bismuth molybdates do not conform to an ideal straight line suggests that the prevailing charge storage follows faradic redox reaction mechanism. Interestingly, octahedron-like bismuth molybdate has delivered a maximum capacitance of 641 Fg− 1 at a scan rate of 5 mV s− 1 while bismuth molybdate electrodes are found to exhibit excellent cycle stability up to 1000 successive CV cycles at a scan rate of 100 mVs− 1.