Theoretical and Experimental Investigation of In Situ Grown MOF-Derived Oriented Zr-Mn-oxide and Solution-Free CuO as Hybrid Electrode for Supercapacitors

Abstract

<p>Recently metal-organic framework (MOF) derived electrode materials have grown considerable research interest in the field of supercapacitor (SC) technology. Herein, MOF-derived Zr-Mn-oxide is successively combined with solution-free CuO nanowires not only to avoid the structural limitations of MOF but also to fabricate a positive-negative hybrid electrode material. The MOF-derived mixed metal oxide prepared through in situ fabrication allows the uniform and unidirectional growth of oriented Zr-Mn-oxide@CuO@Cu. The hybrid electrode exhibited over 100% stability after 20,000 cycles in a three-electrode setup with a wide potential window range of 1.2 V (−0.6 to 0.6 V). Further, the obtained Zr-Mn-oxide@CuO@Cu hybrid electrode exhibited 14.1- and 5.5-fold higher capacity over its MOF-derived Zr-Mn-oxide counterpart (−0.6 to 0.1 V) and CuO (0.0 to 0.5 V), respectively. Additionally, the hybrid device with hybrid Zr-Mn-oxide@CuO@Cu as the positive electrode and reduced graphene oxide as the negative electrode also displayed promising energy and power densities. Furthermore, density functional theory calculations are employed to study the hybrid electrode material's properties. Overall, the unidirectional and vertically aligned MOF-derived Zr-Mn-oxide@CuO@Cu hybrid electrode material with notable electrochemical performance can be useful for the fabrication of next-generation supercapacitor electrodes.</p>