Fe nanoclusters anchored in biomass waste-derived porous carbon nanosheets for high-performance supercapacitor

Metal-nanocluster materials have gradually become a promising electrode candidate for supercapacitor application. The high-efficient and rational architecture of these metal-nanocluster electrode materials with satisfied supercapacitive performance are full of challenges. Herein, Fe-nanocluster anchored porous carbon (FAPC) nanosheets were constructed through a facile and low-cost impregnation-activation strategy. Various characterization methods documented that FAPC nanosheets possessed a mesopore-dominated structure with large surface area and abundant Fe-N4 active sites, which are crucial for supercapacitive energy storage. The optimal FAPC electrode exhibited a high specific capacitance of 378 F/g at a specific current of 1 A/g and an excellent rate capability (271 F/g at 10 A/g), which are comparable or even superior to that of most reported carbon candidates. Furthermore, the FAPC-based device achieved a desired specific energy of 14.8 Wh/kg at a specific power of 700 W/kg. This work opens a new avenue to design metal-nanocluster materials for high-performance biomass waste-based supercapacitors.