Embedding atomic cobalt within hierarchical porous carbon derived from cross-linked polymers for high energy supercapacitors

Abstract

In this study, we have described a straightforward and useful method for synthesizing activated carbon doped with cobalt from cross-linked polymers (Polyvinyl alcohol and Polyvinyl pyrrolidone) with good electrochemical performance . In fact, cobalt (Co) was directly incorporated in the polymers through hydrothermal by varying the amount (0.5 % w/v; 1 % w/v and 2 % w/v) of cobalt precursor (Co(NO 3 ) 2 •6H 2 O) in the Polyvinyl alcohol (PVA) and Polyvinylpyrrolidone (PVP) polymers' solution. The cobalt doped porous carbon shown good features bestowing to the porous structure, metal doping and high conductivity. These characteristics result in more active sites, stored charges, and assistance with the quick passage of electrolytes ions into the porous carbon electrode. At a specific current of 0.5 A g −1 , an assembled symmetric supercapacitor AC-PVA/PVP/Co-1//AC-PVA/PVP/Co-1 supply a significant amount of specific energy and power of 32 W h kg −1 and 401 W kg −1 , respectively. For the symmetric cell, a stability of 91 % up to 10,000 cycles was noted. So, the optimized AC-PVA/PVP/Co has a lot of potential for real-world supercapacitor applications. • Cobalt doped carbon from cross-linked polymer is prepared by one-step activation. • Tuning dopant ratio to optimize performance • AC-PVA/PVP/Co-1 exhibits greatly improved electrochemical performance. • Device recorded a specific energy and power of 27.3 W h kg −1 and 400 W kg −1 .