Cu-Metal Organic Framework Derived Multilevel Hierarchy (Cu/Cu x O@NC) as a Bifunctional Electrode for High-Performance Supercapacitors and Oxygen Evolution Reaction

A Cu-metal organic framework (MOF) wasdesigned and synthesizedand further utilized as a precursor source for MOF-derived multilevelhierarchy (Cu/Cu x O@NC) and, further, studiedfor supercapacitors (both two- and three-electrode systems) and OERactivity. Thedevelopment of a MOFs-derived multilevel hierarchyin a singlestep still remains a challenging task. Herein, we have synthesizednovel Cu-MOF via a slow diffusion method at ambient temperature andfurther utilized it as a precursor source for MOF-derived multilevelhierarchy (Cu/Cu x O@NC, x = 1 and 2). This studies suggest that the organic ligands servedas a source of an N-doped carbon matrix encapsulated with metal oxidenanoparticles which were confirmed by various characterization techniques;further BET analysis reveals a surface area of 178.46 m(2)/g. The synthesized multilevel hierarchy was utilized as an electro-activematerial in a supercapacitor that achieved a specific capacitanceof 546.6 F g(-1) at a current density of 1 A g(-1) with a higher cyclic retention of 91.81% after 10 000GCD cycles. Furthermore, the ASC device was fabricated using Cu/Cu x O@NC as the positive electrode and carbonblack as the negative electrode and utilized to enlighten the commerciallyavailable LED bulb. The fabricated ASC device was further employedfor a two-electrode study which achieved a specific capacitance of68 F g(-1) along with a comparable energy densityof 13.6 Wh kg(-1). Furthermore, the electrode materialwas also explored for the oxygen evolution reaction (OER) in an alkalinemedium with a low overpotential of 170 mV along with a Tafel slopeof 95 mV dec(-1) having long-term stability. The MOF-derivedmaterial has high durability, chemical stability, and efficient electrochemicalperformance. This work provides some new thoughts for the design andpreparation of a multilevel hierarchy (Cu/Cu x O@NC) via a single precursor source in a single step and exploredmultifunctional applications in energy storage and an energy conversionsystem.

Automated summary

In this study, a Cu-metal organic framework (MOF) was designed, synthesized, and utilized as a precursor source for MOF-derived multilevel hierarchy (Cu/Cu x O@NC). The synthesized material showed high durability, chemical stability, and efficient electrochemical performance, making it suitable for energy storage and conversion systems such as supercapacitors and oxygen evolution reaction (OER). This work provides new insights into the design and preparation of multilevel hierarchies with a single precursor source, enabling multifunctional applications in energy storage.