Realization of the superior pseudocapacitive performance in MnS nano-sheets synthesized via microwave radiations: Evaluation of the contributing currents with the Dunn's model

Researchers have shown a significant interest to synthesize supercapacitors exhibiting large specific capacitance and high energy density. Morphology and surface area of electrode can impact supercapacitor’s electrochemical performance. Here, we report mesoporous MnS nanosheets (MnS NS) synthesized using an economical, simple and fast microwave assisted technique, followed by structural, morphological and electrochemical characterizations. The mesoporous nanosheets exhibit a surface area of about 56.5 m 2 g -1 with a pore diameter in the range of 2.2 to 24 nm, offering numerous electro-active sites for electrochemical reactions due to their short diffusion path. MnS NS demonstrate superior specific capacitance of 2776 Fg -1 at 1 Ag -1 , indicating highrate capability. The prepared mesoporous nanosheets exhibit a high energy density of 96.4 Whkg -1 at power density of 249 Wkg -1 and better retention about ~92% after 5000 cycles at 12 Ag -1 . Dunn’s model has been applied to investigate the current contributions due to diffusion controlled and capacitive mechanisms theoretically, demonstrating dominant faradic reactions. This work highlights the promising potential of mesoporous MnS NS electrode and provides a simplest microwave radiation method to synthesize various transition metal based nanosheets for superior electrochemical performance.