Progressive dielectric response of zirconium-doped CeO2 for higher energy storage supercapacitor

초록

Zr-doped CeO2 demonstrates pseudocapacitive electrode material behavior for energy application due to redox reaction and dielectric nature. The electrode material is obtained by a simple, cost-effective method of chemical co-precipitation. The spherical morphology is favorable for energy applications due to its small size of the particle. Actually, our spherical particle size is controlled by a room-temperature synthesis technique. The size of the particles is around 7-13 nm, and it reduces the diffusion length of cations, enabling more and more H+ ions to diffuse into electrode material. Among the samples, the ZC2 samples revealed the optimized dielectric response to the field, which shows the least conductivity. This aspect enables higher energy storage capacity and may return all of the energy without loss. Electrode material stability is secured in CeO2 by Zr dopant. The cyclic voltammetry showed the huge specific capacity of 765.62 F g-1 at 10 mV/s. The electrode presents eminent stability and retains 90 % capacitance after 6200 cycles. Under galvanostatic charge-discharge test, the device unleashes the specific capacitance of 429.86 F g-1, exhibiting significant energy and power density of 76 Wh kg-1 and 435.46 W kg-1. The excellent work of the device is due to the reduced diffusion length, intercalation of ions, and moderate conductivity.

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