锌/空气燃料电池有望成为清洁电源

适合用于要求:容量比较大,充电速度快,并且不污染环境的应用系统。

Effect of preparation routes on activity of Ag-MnO_x/C as electrocatalysts for oxygen reduction reaction in alkaline media

The effect of preparation routes on the physical characteristics and activity of the Ag-MnOx/C composites toward the oxygen reduction reaction （ORR） in alkaline media were studied by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, transmission electron microscopy （TEM）, energy-dispersion spectroscopy （EDS） as well as scanning electron microscopy （SEM） and electrochemical techniques. The results show that more Ag and Mn species present on the surface of the Ag-MnOx/C composite prepared by two-step route （Ag-MnOx/C-2） compared to the one prepared by one-step route （Ag-MnOx/C-1）, which contributes to its superior activity toward the ORR. The higher electron transfer number involved in the ORR can be observed on the Ag-MnOx/C-2 composite and its specific mass kinetic current at -0.6 V （vs Hg/HgO） is 46 mA/μg, which is 23 times that on the Ag/C. The peak power density of zinc-air battery with the Ag-MnOx/C-2 air electrode reaches up to 117 mW/cm^2.

Preparation and properties of transition metal nitrides caged in N-doped hollow porous carbon sphere for oxygen reduction reaction

A series of transition metal nitrides(MxNy,M=Fe,Co,Ni)nanoparticle(NP)composites caged in N-doped hollow porous carbon sphere(NHPCS)were prepared by impregnation and heat treatment methods.These composites combine the high catalytic activity of nitrides and the high-efficiency mass transfer characteristics of NHPCS.The oxygen reduction reaction results indicate that Fe2N/NHPCS has the synergistic catalytic performance of higher onset potential(0.96 V),higher electron transfer number(~4)and higher limited current density(1.4 times as high as that of commercial Pt/C).In addition,this material is implemented as the air catalyst for zinc−air battery that exhibits considerable specific capacity(795.1 mA·h/g)comparable to that of Pt/C,higher durability and maximum power density(173.1 mW/cm2).

Mass production of high-performance single atomic FeNC electrocatalysts via sequenced ultrasonic atomization and pyrolysis process

Mass production of highly efficient,durable,and inexpensive single atomic catalysts is currently the major challenge associated with the oxygen reduction reaction(ORR)for fuel cells.In this study,we develop a general strategy that uses a simple ultrasonic atomization coupling with pyrolysis and calcination process to synthesize single atomic FeNC catalysts(FeNC SACs)at large scale.The microstructure characterizations confirm that the active centers root in the single atomic Fe sites chelating to the four-fold pyridinic N atoms.The identified specific Fe active sites with the variable valence states facilitate the transfer of electrons,endowing the FeNC SACs with excellent electrochemical ORR activity.The FeNC SACs were used as cathode catalysts in a homemade Zn-air battery,giving an open-circuit voltage(OCV)of 1.43 V,which is substantially higher than that of commercial Pt/C catalysts.This study provides a simple approach to the synthesis of single atomic catalysts at large scale.