Lamellar hierarchical lignin-derived porous carbon activating the capacitive property of polyaniline for high-performance supercapacitors

Lignin porous carbons show good potential as carbon electrode materials for supercapacitors, but face problem of low capacitance. Combining lignin porous carbons with polyaniline can achieve high capac-itance. However, capacitance degradation resulting from the poor compatibility between lignin porous carbons and polyaniline has been the major obstacle for their application. In this work, three lignin por-ous carbons with different geometries were used as the hosts to anchor polyaniline for carbon/polyani-line composites via in-situ oxidative polymerization, and the compatibility between lignin porous carbons and polyaniline was investigated. It was determined the lamellar hierarchical lignin porous carbon with crumpled nanosheets can provide a large accessible surface area for the heterogeneous nucleation of aniline, which ensures uniform loading of interpenetrating polyaniline nanofibers. Benefiting from the interpenetrating conductive network and enhanced compatibility, the lamellar hierarchical porous carbon/polyaniline composite possesses a high capacitance of up to 643 F/g at 1.0 A/g and a sufficient capacitance of 390 F/g at 30.0 A/g. This work therefore provides design guidance for carbon hosts in highperformance supercapacitor composite electrodes.(c) 2022 Elsevier Inc. All rights reserved.

Automated summary

Lignin porous carbons have shown potential as carbon electrode materials for supercapacitors, but their low capacitance has been a problem. Combining lignin porous carbons with polyaniline can achieve high capacitance, but the poor compatibility between the two materials has hindered their application. In this study, three different geometries of lignin porous carbons were used as hosts to anchor polyaniline for carbon/polyaniline composites. It was found that the lamellar hierarchical lignin porous carbon with crumpled nanosheets provided a large surface area for nucleation of aniline, resulting in uniform loading of interpenetrating polyaniline nanofibers. The resulting lamellar hierarchical porous carbon/polyaniline composite exhibited high capacitance at different current densities. This work provides guidance for designing carbon hosts in high-performance supercapacitor composite electrodes.