Magnetic Supercapacitors-Particle Morphology Have Significant Impact on the Electrochemical Performance
Joyanti Halder, Sudipta Biswas, Ananya Chowdhury, Debabrata Mandal, Sakshi Kansal, Surbhi Priya, Puja De, Alok Kumar Srivastava, Amreesh Chandra
Abstract
Morphology tuning of the electrode material is a promising approach to improve the overall performance of the supercapacitor. To date, there is no strategy that shows that magnetic-field-dependent supercapacitive behavior can also be tuned by changing the morphology. In this work, using various morphologies of a negative electrode material α-Fe 2 O 3 viz., rod, porous rods, solid spheres (SS), and hollow spheres (HS), the effect of morphology on magnetic supercapacitors is unequivocally established. A theoretical model is also proposed to correlate the electrochemical response with the diffusion behavior of electrolyte ions. Under the application of the 200 Gauss magnetic field, an increment of 55% in the specific capacitance is obtained. The change under magnetic field is correlated with changing surface states. This is proven by corresponding electrocatalysis (HER and OER) performance under magnetic field.