title: Carbon Nanohorn-Derived Graphene Nanotubes as a Platinum-Free Fuel Cell Cathode.
abstract: Current low-temperature fuel cell research mainly focuses on the development of efficient nonprecious electrocatalysts for the reduction of dioxygen molecule due to the reasons like exorbitant cost and scarcity of the current state-of-the-art Pt-based catalysts. As a potential alternative to such costly electrocatalysts, we report here the preparation of an efficient graphene nanotube based oxygen reduction electrocatalyst which has been derived from single walled nanohorns, comprising a thin layer of graphene nanotubes and encapsulated iron oxide nanoparticles (FeGNT). FeGNT shows a surface area of 750 m(2)/g, which is the highest ever reported among the metal encapsulated nanotubes. Moreover, the graphene protected iron oxide nanoparticles assist the system to attain efficient distribution of Fe-Nx and quaternary nitrogen based active reaction centers, which provides better activity and stability toward the oxygen reduction reaction (ORR) in acidic as well as alkaline conditions. Single cell performance of a proton exchange membrane fuel cell by using FeGNT as the cathode catalyst delivered a maximum power density of 200 mW cm(-2) with Nafion as the proton exchange membrane at 60 °C. The facile synthesis strategy with iron oxide encapsulated graphitic carbon morphology opens up a new horizon of hope toward developing Pt-free fuel cells and metal-air batteries along with its applicability in other energy conversion and storage devices.
authors.affiliation: Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory , Pune, Maharashtra, India 411008.|Academy of Scientific and Innovative Research (AcSIR), CSIR-National Chemical Laboratory campus , Pune, Maharashtra, India 411008.
authors.forename: Sreekuttan M
authors.initials: SM
authors.lastname: Unni
authors.affiliation: Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory , Pune, Maharashtra, India 411008.
authors.forename: Rajith
authors.initials: R
authors.lastname: Illathvalappil
authors.affiliation: Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory , Pune, Maharashtra, India 411008.
authors.forename: Siddheshwar N
authors.initials: SN
authors.lastname: Bhange
authors.affiliation: Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory , Pune, Maharashtra, India 411008.
authors.forename: Hasna
authors.initials: H
authors.lastname: Puthenpediakkal
authors.affiliation: Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory , Pune, Maharashtra, India 411008.|Academy of Scientific and Innovative Research (AcSIR), CSIR-National Chemical Laboratory campus , Pune, Maharashtra, India 411008.
authors.forename: Sreekumar
authors.initials: S
authors.lastname: Kurungot
keywords: carbon nanohorns; carbon nanotube; electrocatalyst; fuel cell; oxygen reduction reaction