No abstract

The use of Pt-based cathode catalyst materials hinders the widespread application of anion exchange membrane fuel cells (AEMFCs). Herein, we present a non-precious metal catalyst (NPMC) material based on pyrolysed Fe and Co co-doped electrospun carbon nanofibres (CNFs). The prepared materials are studied as oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts in alkaline and acidic environments. High activity towards the ORR in alkaline solution indicated the suitability of the prepared NPMCs for the application at the AEMFC cathode. In the AEMFC test, the membrane-electrode assembly bearing a cathode with the nanofibre-based catalyst prepared with the ionic liquid (IL) (Fe/Co/IL-CNF-800b) showed the maximum power density (Pmax) of 195 mW cm −2 , which is 78 % of the Pmax obtained with a commercial Pt/C cathode catalyst. Such high ORR

Electrospun polyacrylonitrile (PAN) based carbon nanofibres (CNF) are employed as cathode catalysts in anion-exchange membrane fuel cell (AEMFC) for the first time. The catalysts are prepared via pyrolysis of Co or Fe salt-containing PAN fibre with and without the ionic liquid (IL) additive. The catalyst material preparation is optimised by assessing the oxygen reduction reaction (ORR) activity of different transition metal and nitrogen-doped CNFs in 0.1 M KOH by rotating disc electrode method followed by testing in real AEMFC configuration. The best performance in the AEMFC is observed in case of Fe and IL containing PAN fibre that was pyrolysed at 1000°C and additionally treated in an acid solution (Fe/IL-PAN-A1000). In the AEMFC, the Fe/IL-PAN-A1000 catalyst showed the maximum power density (P max) of 289 mW cm À 2 , which is 82 % of the P max obtained with commercial Pt/C cathode catalyst (352 mW cm À 2).

Owing to its high conductivity, graphene has been incorporated into polymeric nanofibers to create advanced materials for flexible electronics, sensors and tissue engineering. Typically, these graphenebased nanofibers are prepared by electrospinning synthetic polymers, whereas electrospun graphenebiopolymer nanofibers have been rarely reported due to the poor compatibility of graphene with biopolymers. Herein, we report a new method for the preparation of graphene-biopolymer nanofibers using the judicious combination of an ionic liquid and electrospinning. Cellulose acetate (CA) has been used as the biopolymer, graphene oxide (GO) nanoparticles as the source of graphene and 1-butyl-3methylimidazolium chloride ([BMIM]Cl) as the ionic liquid (IL) to create CA-[BMIM]Cl-GO nanofibers by electrospinning for the first time. Moreover, we developed a new route to convert CA-[BMIM]Cl-GO nanofibers to reduced GO nanofibers using hydrazine vapor under ambient conditions to enhance the conductivity of the hybrid nanofibers. The graphene sheets were shown to be uniformly *

No abstract