MnO2-assisted fabrication of PANI/MWCNT composite and its application as a supercapacitor

Manganese dioxide (MnO2) has been used as a sacrificial template to fabricate a polyaniline/multi-walled carbon nanotube (PANI/MWCNT) composite with core–shell structure through a facile route. The as-synthesized samples have been characterized by Raman spectra, Fourier transform infrared spectra, field emission scanning electron microscopy and transmission electron microscopy for their microstructure and morphology. A series of electrochemical measurements have been performed to study the effects of microstructure and morphology of the samples on their capacitive performance. The results indicate that the as-prepared PANI/MWCNT composite with a core–shell structure provides fast ionic channels for electrochemical energy storage. A maximum specific capacitance of 764 F g−1 can be achieved from the hybrid at a current density of 0.25 A g−1, and a fairly good value of 509 F g−1 can be obtained even at a higher current density of 3 A g−1.