In situ preparation of caterpillar-like polyaniline/carbon nanotube hybrids with core shell structure for high performance supercapacitors

An easy and cost-effective approach was developed to deposit polyaniline (PANI) on a single graphitized multiwalled carbon nanotube (GMWCNT) by in situ chemical polymerization. The GMWCNTs were previously grafted with poly(4-vinylpyridine) (P4VP). The morphology and composition of the as-prepared PANI/P4VP-g-GMWCNT hybrids were characterized by the Fourier transform infrared spectroscopy, thermogravimetric analysis and transmission electron microscopy (TEM). The TEM images reveal these PANI/P4VP-g-GMWCNT hybrids possess a core shell structure and take shape as caterpillar. The storage energy performance was investigated by cyclic voltammetry, galvanostatic charge/discharge tests and electrochemical impedance spectroscopy. The PANI/P4VP-g-GMWCNT hybrids exhibit a high specific capacitance up to 1065 F g(-1) and a long cyclic durability with 92.2% capacitance retention over 1000 cycling. A comparative study was carried out between PANI covered on the GMWCNTs with P4VP (PANI/P4VP-g-GMWCNT) and those without P4VP (PANI/GMWCNT). The PANI/P4VP-g-GMWCNT hybrids are superior to PANI/GMWCNT in term of specific capacitance, rate capability and cyclic stability due to their unique structure and full coverage of PANI on the GMWCNTs. (C) 2014 Elsevier Ltd. All rights reserved.