Developing efficient catalysts toward both oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is the core task for rechargeable metal-air batteries.Although integration of two active components should be ...Developing efficient catalysts toward both oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is the core task for rechargeable metal-air batteries.Although integration of two active components should be an effective method to produce the bifunctional catalysts in principle,traditional techniques still can not attain fine tunable surface structure during material-hybridization process.Herein,we present a facile short-time in-situ argon(Ar)plasma strategy to fabricate a high-performance bifunctional hybrid catalyst of vacancy-rich CoFe2O4 synergized with defective graphence(r-CoFe2O4@DG).Reflected by the low voltage gap of 0.79V in two half-reaction measurements,the striking capability to catalyze ORR/OER endows it excellent and durable performance in rechargeable Zn-air batteries,with a maximum power density of 155.2mW/cm^2 and robust stablility(up to 60h).Further experimental and theoretical studies validate its remarkable bifunctional energetics root from plasma-induced surface vacancy defects and interfacial charge polarization between DG and CoFe2O4.展开更多
Mg （MgH2）-based composites, using carbon nanotubes （CNTs） and pre-synthesized titanium based complex （TCat） as the cat- alysts, were prepared by high energy ball milling technique. The use of both catalysts demo...Mg （MgH2）-based composites, using carbon nanotubes （CNTs） and pre-synthesized titanium based complex （TCat） as the cat- alysts, were prepared by high energy ball milling technique. The use of both catalysts demonstrated markedly improved the hydrogen storage performance, e.g. a significant increase of hydrogen release rate and decrease of desorption temperature. The synthesized composites can absorb almost 6 wt% of hydrogen within 3 min at 200 ~C and desorb 6 wt% hydrogen in 10 min at 310 ~C. The influence of CNTs and TCat on desorption temperature was also investigated by using temperature programmed desorption （TPD）. The TPD results reveal that the peak desorption temperature and the onset temperature can be lowered by 109 ~C and 155 ~C, respectively, compared to the non-catalyzed MgH2. The reaction enthalpy and entropy of hydrogen de- sorption for the synthesized MgH2-based composites are calculated by the van＇t Hoff analysis to be 73.1 kJ/mol H2 and 130.2 J/mol H2 K, respectively.展开更多
基金the Project of the Australia Research Council(No.ARC DP200103043)the"111"Project of China(Nos.B07016,B17020)the ARC Discovery Early Career Researcher Award(No.ARC DE180101030)。
文摘Developing efficient catalysts toward both oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is the core task for rechargeable metal-air batteries.Although integration of two active components should be an effective method to produce the bifunctional catalysts in principle,traditional techniques still can not attain fine tunable surface structure during material-hybridization process.Herein,we present a facile short-time in-situ argon(Ar)plasma strategy to fabricate a high-performance bifunctional hybrid catalyst of vacancy-rich CoFe2O4 synergized with defective graphence(r-CoFe2O4@DG).Reflected by the low voltage gap of 0.79V in two half-reaction measurements,the striking capability to catalyze ORR/OER endows it excellent and durable performance in rechargeable Zn-air batteries,with a maximum power density of 155.2mW/cm^2 and robust stablility(up to 60h).Further experimental and theoretical studies validate its remarkable bifunctional energetics root from plasma-induced surface vacancy defects and interfacial charge polarization between DG and CoFe2O4.
基金supported by the Australian Research Council(ARC)
文摘Mg （MgH2）-based composites, using carbon nanotubes （CNTs） and pre-synthesized titanium based complex （TCat） as the cat- alysts, were prepared by high energy ball milling technique. The use of both catalysts demonstrated markedly improved the hydrogen storage performance, e.g. a significant increase of hydrogen release rate and decrease of desorption temperature. The synthesized composites can absorb almost 6 wt% of hydrogen within 3 min at 200 ~C and desorb 6 wt% hydrogen in 10 min at 310 ~C. The influence of CNTs and TCat on desorption temperature was also investigated by using temperature programmed desorption （TPD）. The TPD results reveal that the peak desorption temperature and the onset temperature can be lowered by 109 ~C and 155 ~C, respectively, compared to the non-catalyzed MgH2. The reaction enthalpy and entropy of hydrogen de- sorption for the synthesized MgH2-based composites are calculated by the van＇t Hoff analysis to be 73.1 kJ/mol H2 and 130.2 J/mol H2 K, respectively.
