Tuning electrochemical performance of molybdenum diselenide hybrid capacitors through time and temperature modulation

In this research, the consequence of time and temperature of synthesis of molybdenum diselenide (MoSe 2 ) by the hydrothermal synthesis technique on its structural and electrochemical properties has been studied systematically. A correlation between synthesis conditions, morphology, and electrochemical performance has been established by conducting performance testing using a symmetric supercapacitor cell design. The sample that shows the best results among all synthesized samples is MoSe 2 , with synthesis conditions of 180 °C for 12 h. Its specific capacitance reaches ∼251 F g −1 at 10 mV s −1 of scan rate, while energy density reaches ∼31 Wh kg −1 at 3 A g −1 of current density. Electrochemical studies show a charge storage behavior of MoSe 2 is based on hybrid-type methods. The optimal electrode sample retains almost 80% of its capacity for 1000 cycles, suggesting high stability of the electrode material. • The effect of hydrothermal treatment time and temperature on the electrochemical properties of MoSe 2 was studied. • Nano-flower-like MoSe 2 synthesized by controlling conditions results in a higher surface area and ion movement. • MoSe 2 (180°C, 12 h) gives ~251 F g -1 at 100 mV s -1 . • Specific energy of 30 Wh kg -1 can be achieved at 3 A g -1 with good electrochemical stability.