MOF-derived nickel cobaltite: a pathway to enhanced supercapacitor performance†
Abstract
A streamlined design for nanoarchitecture can substantially enhance the performance of battery-type electrodes, leading to advanced hybrid supercapacitors (HSCs) with improved redox properties. Metal–organic frameworks (MOFs) are promising for electrochemical energy storage; however, they often suffer structural damage during calcination. We present a method to fabricate hierarchically layered sheet-like NiCo2O4 (NCO) nanostructures from MOFs. These nanostructures facilitate improved electron and ion transport while offering numerous electroactive sites. As supercapacitor electrodes, they exhibit a high specific capacity (∼597 mA h g−1 at 1 A g−1) and notable rate capability (69.2% retention). The NCO//AC HSC demonstrates a broad voltage window, a specific capacitance of ∼152 F g−1 at 1 A g−1, a high energy density (∼47.3 W h kg−1 at ∼908.2 W kg−1), and excellent cycle stability (∼90.8% retention after 10 000 cycles). This approach is both cost-effective and scalable for commercial energy storage applications.