Supercritical fluid synthesized Cu2ZnSnS4-Polyaniline nanocomposites for supercapacitor application

In the work, Cu2ZnSnS4 (CZTS)/Polyaniline (PANI) nanocomposites was successfully synthesized by an in-situ supercritical water reaction from the mixture of CZTS-precursors and PANI. The synthesized samples were characterized by X-ray diffraction, TEM, thermogravimetry/differential thermal analysis (TG-DTA), scanning electron microscopy, and elemental mapping of CZTS powder. In order to evaluate the electrochemical performance of CZTS nanoparticles and CZTS/PANI nanocomposites, their supercapacitor electrodes were fabricated. The electrochemical experiment revealed that the specific capacitance of CZTS/PANI in 1 M KOH aqueous electrolyte at a current density of 2.5 A/g was 371 F/g, which was significantly more than the specific capacitance of the pure CZTS sample (271 F/g) after 1000 cycles also, the composite retained 97% of its capacitance. Thus, it can be concluded that the reduced electrolyte charge-transfer resistance and ion-diffusivity can be the cause of enhanced conductivity and a large surface of the material, which synergistically improved the capacitive performance of the electrode material.