Magnetic Supercapacitors-Particle Morphology Have Significant Impact on the Electrochemical Performance

Morphology tuning of the electrode material is a promisingapproachto improve the overall performance of the supercapacitor. To date,there is no strategy that shows that magnetic-field-dependent supercapacitivebehavior can also be tuned by changing the morphology. In this work,using various morphologies of a negative electrode material & alpha;-Fe2O3 viz., rod, porous rods, solid spheres (SS),and hollow spheres (HS), the effect of morphology on magnetic supercapacitorsis unequivocally established. A theoretical model is also proposedto correlate the electrochemical response with the diffusion behaviorof electrolyte ions. Under the application of the 200 Gauss magneticfield, an increment of 55% in the specific capacitance is obtained.The change under magnetic field is correlated with changing surfacestates. This is proven by corresponding electrocatalysis (HER andOER) performance under magnetic field.

Automated summary

The morphology of the electrode material plays a crucial role in improving the performance of supercapacitors. This study demonstrates the influence of morphology on magnetic supercapacitors by using different morphologies (rod, porous rods, solid spheres, and hollow spheres) of α-Fe2O3 as the negative electrode material. Additionally, a theoretical model is proposed to explain the correlation between the electrochemical response and the diffusion behavior of electrolyte ions. Under a 200 Gauss magnetic field, a 55% increase in specific capacitance is achieved, which is attributed to the change in surface states, as evidenced by the corresponding electrocatalysis performance.