Nano-fe₃o₄/carbon nanotubes composites by one-pot microwave solvothermal method for supercapacitor applications

Carbon nanotubes (CNTs) are being increasingly studied as electrode materials for su-percapacitors (SCs) due to their high electronic conductivity and chemical and mechanical stability. However, their energy density and specific capacitance have not reached the commercial stage due to their electrostatic charge storage system via a non-faradic mechanism. Moreover, magnetite (Fe₃O₄) exhibits higher specific capacitance originating from its pseudocapacitive behaviour, while it has irreversible volume expansion during cycling. Therefore, a very interesting and facile strategy to arrive at better performance and stability is to integrate CNTs and Fe₃O₄. In this study, we demonstrate the microwave-solvothermal process for the synthesis of Fe₃O₄ nanoparticles uniformly grown on a CNT composite as an electrode for SCs. The synthesized Fe₃O₄/CNT composite delivers a reversible capacitance of 187.1 F/g at 1 A/g, superior rate capability by maintaining 61.6% of 10 A/g (vs. 1 A/g), and cycling stability of 80.2% after 1000 cycles at 1 A/g.