[Pending] Symposium on Nanomaterials for Energy: Graphitic Petals for Electrochemical Charge Storage
The need for high-density electrochemical energy storage in today’s world is self-evident, and we have investigated the advantages offered by graphitic petals (GPs) to achieve this end. The controlled growth of GPs permits nano-texturing of a substrate, producing an enhanced carbon-based material to enable new technologies that might benefit from such features. The conditions required for the rapid growth of GPs in a microwave plasma chemical vapour deposition system have been investigated, and the controlled growth of these highly porous nanostructures has been achieved. We have investigated the fabrication of various hybrid nanoarchitectures of GPs on a number of substrates that include a) thermally oxidized Si wafers, b) commercial carbon nanotube substrates (buckypaper), and c) highly conductive carbon cloth (CC). GPs grown on buckypaper and CC are ideally suited for flexible-electrode supercapacitors and micro supercapacitor applications. By electropolymerization of aniline monomers to form a thin polyaniline (PANI) film, we find that CC/GP/PANI electrodes yield greatly improved capacitive performance with a high specific capacitance of 1500 F/g (based on PANI mass) at 2 mV/s (3 times greater than that of CC/PANI) and a large area-normalized specific capacitance of ~2.5 F/cm2 (equivalent to >200 F/cm3) at 1 A/g (~10 times greater than that of CC/PANI in 1 M H2SO4 electrolyte). These levels of electrochemical storage performance are also competitive with the best prospective supercapacitor electrode materials recently reported in the literature. To demonstrate a practical application, we have used flexible supercapacitors based on this technology to power LED devices. Such results indicate a promising future for GP-based electrodes for the next generation of supercapacitors.
Jawaharlal Nehru Centre for Advanced Scientific Research
Indo-US Science & Technology Forum
NSF - Office of International Science and Engineering
Researchers should cite this work as follows:
MGRN 129, Purdue University, West Lafayette, IN