Three-dimensional honeycomb-like porous carbon derived from tamarisk roots via a green fabrication process for high-performance supercapacitors

The porous carbon materials derived from biomass have become the most promising candidates for electrochemical energy conversion and storage due to their renewability and sustain ability. Herein, we present a simple activation and carbonization approach to successfully fabricate a novel tamarisk root-based honeycomb-like porous carbon (TRHPC) by using biomass tamarisk roots as carbon precursor and mixed NaCl and ZnCl2 as hybrid activators. The TRHPC exhibits good electrochemical properties with high specific capacitance 293 F g(-1) at a current density of 0.5 A g(-1) and high-rate performance (61.4% capacitance retention from 0.5 to 50 A g(-1)) when it is applied for supercapacitor electrode. Moreover, the symmetric supercapacitor assembled based on the optimized TRHPC electrode materials represents a high energy density of 16 Wh kg(-1) at a high power density of 160 W kg(-1) and possesses excellent stability with 92% capacitance retention after 10,000 cycles in 0.5 M Na2SO4 electrolyte. The excellent electrochemical performance of TRHPC with three-dimensional honeycomb-like porous structure reveals its significance as electrode materials for supercapacitor applications.