One-pot synthesis of carbon nanotube–graphene hybrids via syngas production
Multi-walled carbon nanotubes (MWCNTs) are limited by entanglement, and it is rather difficult to prevent graphene stacking in a polymer composite. These two challenges can be addressed by developing a MWCNT–graphene hybrid where MWCNTs and graphene are born as twins. We in this study employed a syngas production method using microwave irradiation for a one-pot synthesis of porous, crumpled and loose MWCNT–graphene hybrids, investigated the substrate compositions, measured their performance as electrodes for energy storage devices, and proposed the synthesis mechanisms. A number of hybrids, including MWCNT–graphene, MWCNT–cup-stacked CNT and MWCNT–graphitic nanofiber, were synthesized on Cr–Ni, Fe–Ni and Ni–CeO2 substrates, respectively. TEM analysis shows that the two challenges have been markedly addressed in the hybrids. They performed better in terms of capacitive properties than commercial MWCNTs.