Eco-friendly synthesis of hierarchical hollow Cu₇S₄ nanotubelets using volatile organosulfurs for high-performance supercapacitors

Herein, a novel and solvent free green chemistry approach has been investigated for synthesis of 1D hollow Cu 7 S 4 nanotubelets on Cu-substrate using volatile organosulfurs of Allium sativum L at room temperature for supercapacitors. In addition to validation of the green sulfurization of the pristine Cu surface, the Cu 7 S 4 exhibits vertically aligned 1D hierarchical tubular morphologies. The X-ray diffraction (XRD) patterns confirm the anilite phase of Cu 7 S 4 , and energy dispersive X-ray (EDX) reveals the presence of Cu and S elements. The Brunauer–Emmett–Teller (BET) specific surface area is found to be 2.07 m 2 g − 1 along with a total pore volume of 2.12 × 10 − 2 cm 3 g − 1 . Supercapacitive performance of the hollow Cu 7 S 4 as active electrode material was evaluated using cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) measurements in 0.5 M H 2 SO 4 electrolyte. Results show that a high specific capacity of 1110.65 Fcm − 2 at a current density of 1 Acm − 2 . Moreover, the Cu 7 S 4 electrode demonstrates a high energy density of 168.42 Wcm − 2 , power density of 990.7 Whcm − 2 , and good cycling stability, suggesting that the hollow Cu 7 S 4 nanotubelets are promising electrodes for supercapacitors.