Enhanced capacitance of MXene synthesized through safer route and its composite with amino graphene oxide

Abstract

Two-dimensional (2D) MXene has received a lot of attention recently due to its outstanding mechanical, electrical, and thermal stability. However, poor specific capacitance severely limits its application towards supercapacitor. Moreover, the existing hazardous synthesis route of MXene is also a concern in the scientific community. On the other hand, amino graphene oxide (AGO) has very high electrical properties yet it is thermally unstable beyond 160 °C. Therefore, the present work reports a novel composite consisting of MXene and AGO, i.e., MAC, capable of exhibiting superior electrical properties along with the elevated thermal stability. Importantly, the MXene has been synthesized by a greener technology by using a mixture of concentrated HCl and NH4F to produce HF (etching agent) in situ rather than its ex situ addition. The formation of MAC is confirmed from microscopic (FE-SEM), thermal (TGA), diffractometric (XRD), spectroscopic (FTIR and XPS), and BET analyses. The thermogravimetric (TG) result shows that there is a significant improvement in thermal stability of AGO in the MAC. Moreover, synthesized MXene using safer route and MAC shows significant improvement in specific capacitance (2084.39 F g−1 at scan rate of 5 mV s−1 in PBS buffer solution) which is approximately twice than most of the reported capacitance in the literature. The improved thermal and electrochemical properties of MXene-AGO composite enhance its the potential use as supercapacitor.