High-performance supercapacitor poplar catkin Ag/carbon fibers composites

Abstract

An efficient method is described to fabricate carbonized wood fibers (CWF)-based electrode materials decorated with Ag particles (CWF-Ag) through electroless plating, and further carbonization from natural biomass poplar catkin and poplar fiber. Intrinsic physical advantages of poplar catkin fibers provide a chance of evenly dispersed Ag layer in addition to successful modulation of porosity and conductivity. However, the separation process resulted in cross-linked structures defect of poplar fibers, which impeded Ag particles to uniformly disperse. CWF-Ag from poplar catkin (CWF-Ag-poplar catkin) displays well-defined electrochemical performance for supercapacitors on account of its large specific surface area (745 m 2 /g), and hierarchical porous structure. Remarkably, CWF-Ag-poplar catkin achieves a high specific capacitance of 250 F/g at a current density of 1 A/g in 1 M KOH electrolyte that is about 1.3 times higher than CWF-Ag-poplar fiber (190 F/g). The result is due to uniform loading of silver on fibers. CWF-Ag-poplar catkin shows good rate capability and outstanding cycling stability up to 5000 times (only 5% loss of capacitance). The present study provides a simple and efficient approach (electroless plating) to design a high capacitance and stable supercapacitor electrode from natural biomass without treatment.