Synthesis And Electrochemical Properties Of Al-H₂O₂ Semi Fuel Cell Cathode Non-noble Metal Catalysts

Al-H2O2 semi-fuel cells,employing H2O2 as oxidant,can work in anaerobic environments such as underwater and space.They have many advantages,such as high energy density,stable discharge voltage,simple structure,long shelf life,the use of safety,non-ecological pollution and short mechanical charging time.In this paper,we prepared porphyrin Fe-N-C catalyst,perovskite La1-xSrxMnO3 catalyst,spinel Co3O4 and NiCo2O4 catalysts.These electrodes are characterized by scanning electron microscope(SEM),Transmission Electron Microscopy(TEM),X-ray diffractometer(XRD)and Thermogravimetric/Differential Thermal Analysis(TG-DTA).The catalytic performances for H2O2 electro-reduction are tested by cyclic voltammetry(CV)and chronoamperometry(CA)methods.Besides,we assembled Al-H2O2 semi-fuel cells employed the prepared materials as cathode and A1 as anode.The factors that affect the battery performance are discussed.Porphyrin Fe-N-C catalyst was prepared through metal-assisted polymerization.Catalysts with different pretreated methods for carbon supports?Fe content?nitrogen source and firing steps for hydrogen peroxide electro-reduction are studied.The results indicated that when carbon support was pretreated by 2 mol·L-1 HCl,Fe content was 0.2wt%?nitrogen source was the p-nitroaniline and roasting times was the first time,the catalytic activity was the best.When the H2O2 concentration of 0.6 mol·L-1and KOH concentration of 3 mol·L-1 and the electrode potential was-0.4 V,the current density reached-79.0 mA·cm-2.An Al-H2O2 semi-fuel cell was set up with Porphyrin catalyst as cathode,Al electrode as anode.The power density was 51.4 mW·cm2 with the open-circuit voltage of 1.3 V.Perovskite La1-xSrxMnO3(x = 0.2,0.4,0.6,0.8)powder were prepared using a sol-gel method,with chitosan as the gelling agent.Results revealed that the reduction current density reached to-160.9 mA·cm-2 when the electrode potential was-0.4 V and the La1-xSrxMnO3 with x = 0.6 in the H2O2 concentration of 0.6 mol·L-1.An Al-H2O2 semi-fuel cell was set up with La1-xSrxMnO3catalyst as cathode,Al electrode as anode.The power density was 87.6 mW·cm-2 with the open-circuit voltage of 1.41 V.Spinel Co3O4 and NiCo2O4 nanowires were prepared using a solution-based synthetic route.Using Co3O4 and NiCo2O4 nanowire as cathode electrode,I designed and tested Al-H2O2 semi-fuel cell.The result shows that the battery's employed NiCo2O4 as cathode has a better performance.The optimal working conditions are that the cathode electrolyte is 3 mol·L-1 KOH + 0.4 mol L-1 H2O2,anode electrolyte is 3 mol·L-1 KOH,electrolyte flow rate is 80 ml·min-1,the temperature is 57 ? and the battery displayed a peak power density of 120.0 mW·cm-2 at 172.0 mA·cm-2.