Preparation And Characterization Of Cathode Electrocatalyst For Aluminum-air Battery

Aluminum-air battery based on the (anodeAl metal|electrolyte|cathodeoxygen)configuration, owing a theoretical open-circuit voltage of2.73V and specific energy(8.1kWh/kg of Al;2.8kWh/kg of cell reactants), have attracted worldwide attentionas a promis ing power source for large-scale applications such as electric vehicles andstationary energy storage. While the nature of the catalyst plays a key role in theoverall performance of aluminum-air battery and the increase of the activity ofcathode materials for a few times higher is a formidable challenge that requires afundamental breakthrough. Graphene nanosheets (GNS) have showned great promisein many applications, because of its unique nanostructure, extraordinaryphysico-chemical properties and strong mechanical strength. In this paper, GNS havebeen first employed as catalyst’s supporter to manufacture aluminum-air battery.GNS were prepared by thermal expansion method, and Platinum-Cobalt alloynanoparticles deposited on graphene were prepared by ethylene glycol reductionprocess under the assistance of the microwave. The structure, morphology,composition and surface properties of the as-prepared catalysts are characterized byX-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanningelectron microscope (SEM) and Infrared Spectroscopy (IR). moreover, Cyclicvoltammetry (CV), linear sweep voltammetry (LSV) and constant current dischargewere used to test the oxygen reduction electrode.The results showed that the graphene oxide (GO) made by pre-oxided is betterthan no pre-oxided procedure, and when the time of icebath have been increased, GOwill has better performance. GNS made by using PANI as modification have biggerBET surface and better oxygen reduction reaction (ORR). Particles were uniformlydispersed on the surface of graphene, and the particle size was about3nm andexhibited high electrochemical activity, when the mass rations of platinum and cobaltare1:2.When GNS composited with XC-72and WMCNT respectively, it can improvethe performance of the catalyst. When GO to XC-72quality ratio is4:1, the airbattery, at the same discharge conditions, have a higher discharge platform. In thedischarge conditions of10mA,20mA,30mA and40mA, the discharge platform canreach1.31V,1.0V,0.54V,0.48V. When the GO and the ratio of the MWCNTquality is2:1, In the discharge conditions of10mA,20mA,30mA and40mA, thedischarge platform can reach1.38V,0.65V,0.62V,0.58V.In order to improve thediffus ion of oxyen, reduce the leakage of electrolyte and the corrosion of current collector, we use the model of diffus ion layer-current collector-diffusionlayer-catalyst layer to make the cathode.