Affiliation:
1. Tianjin University of Science & Technology
Abstract
Abstract
Hierarchical porous carbon aerogels were synthesized from liquefied wood via physical and chemical activation. The morphology and structure of the KOH treated carbon aerogel (K-LWCA) and steam treated carbon (H-LWCA) were systematically investigated by SEM, N2 adsorption, FTIR, XRD and XPS, and the electrochemical properties were evaluated based on cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. The H-LWCA and K-LWCA had the high reached specific surface area (1996 and 1780 cm2 g− 1, respectively) and developed hierarchical porous structures. Compared with H-LWCA, K-LWCA showed the higher specific capacitance, better rate performance and superior cyclic stability due to more defects and hydrophilic functional groups. As expected, the K-LWCA exhibited the optimal mass-specific capacitance of 201.47 F g− 1 at 0.5 A g− 1, and achieved ideal capacitance retention of 70.15% at 20 A g− 1 as well as exceptional cycling stability of 94.11% retention after 5000 cycles. Moreover, the button symmetric supercapacitor device assembled based on K-LWCA demonstrated a specific capacitance of 117.78 F g− 1 at 0.5A g− 1 and presented an energy density of 9.2 Wh kg− 1 at a power density of 375W kg− 1. Accordingly, this work provides a novel approach for the preparation of biomass-derived carbon aerogel electrode materials in practical supercapacitor applications.
Publisher
Research Square Platform LLC