Ultrafast high-capacitance supercapacitors employing carbons derived from Al-based metal-organic frameworks

Abstract

Compact supercapacitors (SCs) have garnered significant attention due to their potential to replace bulky aluminum electrolytic capacitors (AECs) in alternating current (AC) line filtering applications. However, the slow response speeds of conventional SCs based on activated carbons are inadequate for such high-frequency applications. Therefore, this paper presents a study on high-frequency SCs using metal-organic framework (MOF)-derived carbon (MDC) electrode materials. Here, the carbonization of the selected MOF results in highly conductive carbons with hierarchical pore structures that offer substantial advantages for use as electrode materials in ultrafast SC applications. Consequently, the as-fabricated MDC SCs exhibit significant areal and volumetric capacitances of 2.41 mF cm–2 and 5.74 F cm–3, respectively, at 120 Hz, coupled with a rapid response speed indicated by a phase angle of –80.1°. Notably, this performance is superior to that of the state-of-the-art high-frequency SCs based on carbon materials. The results underscore the potential of MDCs as electrode materials for use in ultrafast SCs, with eventual implications for the miniaturization of electronic devices.