Composite Fe<sub>3</sub>O<sub>4</sub>-MXene-Carbon Nanotube Electrodes for Supercapacitors Prepared Using the New Colloidal Method

oleh: Wenyu Liang, Igor Zhitomirsky

Format: Article
Diterbitkan: MDPI AG 2021-05-01

Deskripsi

MXenes, such as Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>, are promising materials for electrodes of supercapacitors (SCs). Colloidal techniques have potential for the fabrication of advanced Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub> composites with high areal capacitance (C<sub>S</sub>). This paper reports the fabrication of Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub>-Fe<sub>3</sub>O<sub>4</sub>-multiwalled carbon nanotube (CNT) electrodes, which show C<sub>S</sub> of 5.52 F cm<sup>−2</sup> in the negative potential range in 0.5 M Na<sub>2</sub>SO<sub>4</sub> electrolyte. Good capacitive performance is achieved at a mass loading of 35 mg cm<sup>−2</sup> due to the use of Celestine blue (CB) as a co-dispersant for individual materials. The mechanisms of CB adsorption on Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub>, Fe<sub>3</sub>O<sub>4</sub>, and CNTs and their electrostatic co-dispersion are discussed. The comparison of the capacitive behavior of Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub>-Fe<sub>3</sub>O<sub>4</sub>-CNT electrodes with Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub>-CNT and Fe<sub>3</sub>O<sub>4</sub>-CNT electrodes for the same active mass, electrode thickness and CNT content reveals a synergistic effect of the individual capacitive materials, which is observed due to the use of CB. The high C<sub>S</sub> of Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub>-Fe<sub>3</sub>O<sub>4</sub>-CNT composites makes them promising materials for application in negative electrodes of asymmetric SC devices.