Elucidating the pseudocapacitive mechanism of ternary Co-Ni-B electrodes-Towards miniaturization and superior electrochemical performance for building outmatched supercapacitors

Ternary bi-metallic borides have been prepared by administrating two different solvent media utilized through co-precipitation process with particles dimension ranging from 3 to 5 nm. The X-ray photoelectron spectroscopy suggests the presence of redox states in the cobalt-nickel based bi-metallic borides that promotes excess electroactive sites. The outstanding stability of bimetallic borides has been estimated by measuring relaxation time (T-2) in solvent medium. The surface area has been evaluated about 151.302 m(2) g(-) (1)with associated pore diameter of 6.57 nm. Moreover, the ternary bi-metallic electrode exhibited excellent pseudocapacitance with exceptional specific capacitance (SC) of 4835 Fg(- 1) (606 mAh g(-1)) at 5 Ag-1 by upholding cycling retention of-94.2% over 15,000 cycles. Also, different concentrations of sodium hydroxide (NaOH) electrolyte (0.5, 1.0 & 1.5 M) are employed for comparative study to achieve optimal electrochemical performance. Simultaneously, an electrode configuration is designed with cobalt-nickel -boron (Co-Ni-B) 1:1:0.15 as positive and carbon black as negative electrodes to fabricate asymmetric device. The device illuminates a commercial light emitted diode (LED similar to 1.8 V) to justify the electrode performance and their full-scale deployment with a device efficiency-363 Fg(- 1) (358 mAh g(-1)) and an energy density of 114 Wh kg(-1.)

Automated summary

Ternary bi-metallic borides with particle sizes ranging from 3 to 5 nm were prepared using co-precipitation method. X-ray photoelectron spectroscopy revealed the presence of redox states in these borides. These ternary bi-metallic borides demonstrated outstanding stability and electrochemical performance in solvent medium.