Porous spinel oxide composites supported by self-generated carbon from ZIF-modified chitosan aerogels for high energy supercapacitor electrodes

Abstract

In this work, porous spinel–spinel composite electrode materials based on aerogel frameworks derived from chitosan and architectures derived from ZIF-67 compounds were constructed using a systematic design approach. The chitosan aerogel template serves as both a precursor for self-generated conductive carbon and a three-dimensional porous scaffold, and was used to create porous Cu-based spinel oxides (CuMn₂O₄ and CuCo₂O₄). Then, the spinel surface was covered with a layer of ZIF-67 (a cobalt-based metal–organic framework), which was thermally transformed into porous spinel (Co₃O₄) to fabricate a hierarchical composite with synergistic effects and superior electrochemical properties. The structural, morphological, and compositional properties confirmed the successful formation of the prepared aerogel-derived materials. The electrochemical performance was evaluated using a three-electrode setup. The Co₃O₄/CuMn₂O₄ composite exhibited high specific capacitance of 3158 F g⁻¹ at 1 A g⁻¹ and stability of more than 80% after 4000 cycles. These results show that the simple, economical, and effective method for creating supercapacitor electrodes makes this type of aerogel-based structure a promising candidate for next-generation energy storage applications.