Preparation And Electrochemical Performance Of LSCF-GDC For SOFC Via Electrospinning

Solid oxide fuel cell(SOFC) using all-solid-state ceramic materials,it is a kind of device to transform chemical energy in fuel into electrical power.it possess ecological friendly,highly utilization ratio,well security property,green environmental protection and so on.Developing SOFC under 500～800℃ has become the direction of SOFCs development in recent years.however,Some problems,such as the increase of polarization resistance and reduce of catalytic activity,mainly reflect in cathode aspects.Therefore how to keep highly catalytic activity and reduce the polarization resistance of cathode has became the key direct of research. A materials possesses La1-xSrxCo1-yFeyO3-δ with perovskite structure has good property of ionic-electron property,meanwhile,it also possesses low thermal expansion coefficient and high electro-catalytic activity become the prospect of cathode material in SOFC.In addition,the characterization of the internal cathode structure is the key of cathode property.besides,the LSCF cathode with the three-dimensional network structure is the key to decide the property of cathode, it has which have high surface area ratio,continuous path and porosity.Electrospinning method is a technique taking advantage of polymer solution or melts drawed and formed into injection flow and become nanofiber network structure.In this paper,By using organic and complex organic compounds.A precursor solution contains many metal ionic was prepared.Unform and stable La0.6Sr0.4Co0.2Fe0.8O3-δ fiber was prepared by using electrospinning method, research the influence on the process parameters in contenting of PVP、operating voltage、working distance and the rate of feed when operate electrospinning.LSCF nanofiber was characterized through TG-DTA XRD,SEM,EDS,and TEM respectively. Through the calcining at 800℃.The phase,microstructure,grain size can be noticed.it possess singly-crystal structure and with the perovskite structure.The fiber electrospinning was dissolved and grind, By using screen printing method it was coated on the surface of cathode, symmetric cell has been synthesised.In order to reduce the polarization resistance of the cathode. In this paper, we have synthesized LSCF-GDC composite cathode materials by impregnating Ce0.9Gd0.1O1.95(GDC) into the fibrous La0.6Sr0.4Co0.2Fe0.803-δ(LSCF) cathode, and the symmetric cell (LSCF+GDC‖ GDC ‖LSCF+GDC) were prepared using LSCF-GDC composite as cathode materials. LSCF-GDC composite cathode has a better electrochemical performance. The impedance of composite cathode was 0.64 Ω·cm2, 0.42 Ω·cm2,0.27 Ω·cm2,0.38 Ω·cm2 respectively under air atmosphere and 750℃ working temperature when the weight percent of GDC and LSCF was 0:1,0.17:1, 0.38:1,0.54:1.Furthermore,GDC fibers can be sythenized by electrospinning method and it also be mixed with LSCF nanofibers, The impedance of the LSCF-GDC cathode is 0.53、0.33�'�0.73Ω·cm2when the weight ratio of mixed GDC is 10,20and 30,respectively.The cells(NiO+YSZ‖ YSZ‖ LSCF) and (NiO+YSZ‖ YSZ‖ LSCF+GDC) were prepared, which cathode is LSCF pure cathode, LSCF composite cathode with ratio of 38 solution and 20 GDC nanofiber,The results showed that the maximum power density of cells were 0.56 wcm-2、0.81 wcm-2 and 0.68wcm-2, respectively.