Lignosulfonate functionalized nanomaterials for enhancement of the electrochemical performance of polyaniline

The electrochemical enhancement of polyaniline (PANI) by adding nanomaterials is closely related with the dispersion state of the nanomaterials in PANI. Herein, we demonstrate the fabrication of well-mixed PANI/nanomaterials composites through solid-phase exfoliation and subsequent in-situ polymerization. Bulk molybdenum disulfide (MoS2) or carbon nanotube (CNT) bundles were firstly ball-milled in the presence of calcium lignosulphonate to provide lignosulfonate (LS) noncovalently functionalized MoS2 nanosheets or CNTs, which were then used as skeletons for in-situ polymerization of aniline. The resulted nanocomposites exhibited enhanced electrochemical properties as compared with pure PANI. Typically, the ternary composite PANI/MoS2-LS/CNT-LS delivered a specific capacitance of 458.9 F/g, a 63% improvement than PANI at 1 A/g in a three-electrode system. Furthermore, excellent cycle stability (86% capacitance retention after 10, 000 charge-discharge cycles) and high specific energy (10.9 Wh/kg at specific power of 265.3 W/kg) were obtained in a coin-type symmetric supercapacitor. The study provides an efficient and facile approach for fabrication of conductive polymer/nanomaterials composite for supercapacitors with good stability and performance.