Ni-Zn ferrites as supercapacitors and gas sensors synthesized using precursor-combustion method

Abstract

Ni sub(1-x)Zn sub(x)Fe sub(2)O sub(4) (x = 0.0, 0.2, 0.4, 0.6, 0.8) ferrites were synthesized by the precursor-combustion method employing mixed metal succinato-hydrazinates as the precursors. The ferrites were characterized by X-ray diffraction, infrared studies, X-ray photoelectron spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy, and Brunauer Emmett Teller analysis. The study of their electrical, magnetic, and dielectric properties highlights the impact of substituting nickel with zinc in the ferrite system. Cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy revealed the faradaic redox behavior in all the synthesized ferrites. Ni sub(0.6)Zn sub(0.4)Fe sub(2)O sub(4) showed the maximum specific capacity of 83.97 C g sup(-1) at a current density of 1 A g sup(-1). Additionally, Ni sub(0.6)Zn sub(0.4)Fe sub(2)O sub(4) selectively exhibited a good response of 31 percent towards NH sub(3) gas at an operating temperature of 100 degrees C. The response and recovery times were 2 and 4 s, respectively.