An intermediate-temperature solid oxide fuel cell with electrospun nanofiber cathode

Abstract

Lanthanum strontium cobalt ferrite (LSCF) nanofibers have been fabricated by the electrospinning method and used as the cathode of an intermediate-temperature solid oxide fuel cell (SOFC) with yttria-stabilized zirconia (YSZ) electrolyte. The three-dimensional nanofiber network cathode has several advantages: (i) high porosity; (ii) high percolation; (iii) continuous pathway for charge transport; (iv) good thermal stability at the operating temperature; and (v) excellent scaffold for infiltration. The fuel cell with the monolithic LSCF nanofiber cathode exhibits a power density of 0.90 W cm À2 at 1.9 A cm À2 at 750 C. The electrochemical performance of the fuel cell has been further improved by infiltration of 20 wt% of gadolinia-doped ceria (GDC) into the LSCF nanofiber cathode. The fuel cell with the LSCF-20% GDC composite cathode shows a power density of 1.07 W cm À2 at 1.9 A cm À2 at 750 C. The results obtained show that one-dimensional nanostructures such as nanofibers hold great promise as electrode materials for intermediate-temperature SOFCs.

Corn-cob like nanofibres as cathode catalysts for an effective microstructure design in solid oxide fuel cells

“…12,20 Generally, the first arc (1) can be assigned to the charge transfer process and the second arc (2) provides an information about the dissociation of oxygen molecules and adsorption of oxygen gas into the cathode. 21,27,[38][39] Based on the same material compositions, there was no big difference in the intrinsic property of the cathode. However, it was interesting that the lower total resistance of the YSZ@LSM nanofibrous cathode came from the slightly smaller second arc (2) than the LSM@YSZ nanofiber based cathode, indicating that the YSZ@LSM structure poseess more active sites for the dissociation of oxygen molecules and adsorption of oxygen gas.…”

“…These continuous nanofibers transferred electrons and oxygen ions, respectively, better to the whole electrode with less interruption. 27,[31][32] Furthermore, from the formation of unique microstructure structure by a nanofibrous web, higher surface area of the architected nanostructure was created, which is greatly related to the large number of active reaction sites.…”

“…[22][23][24][25][26] Among these, nanofibers have been attractive to the SOFC field because of their highly porous feature with large surface-to-volume ratio and surface areas highly exposed to the surrounding environment. [27][28] To fabricate a one dimensional continuous long nanofiber, electrospinning method by employing a strong electric field to an inserting polymeric liquid source is currently the most powerful technique that is fast and efficient to widely apply in many areas. [29][30] In our previous study, nanofibrous…”

Evaluation of double perovskite Sr2FeTiO6−δ as potential cathode or anode materials for intermediate-temperature solid oxide fuel cells

“…During the past, Cobalt containing oxides of different composition, such as Ln 1 À x Sr x Co 1 À y Fe y O 3 À δ (Ln=rare-earth) [8][9][10][11][12], Ba 1 À x Sr x Co 1 À y Fe y O 3 À δ [5,[13][14][15][16], LnBaCo 2 O 5 þ δ (Ln=rare-earth) [17][18][19][20][21], and RBa(Co, M) 4 O 7 (R=Y, Ca, In and M=Zn, Ga, Al) [22][23][24][25][26][27], have been extensively exploited as potential cathode materials for IT-SOFCs, owing to their excellent electrocatalytic activity for the oxygen reduction reaction (ORR). However, most of these materials usually show poor chemical stability, insufficient chemical compatibility with the electrolyte, high thermal expansion coefficient, high cost of cobalt element and easy evaporation.…”

Microwave synthesis & sintering of Sm and Ca co-doped ceria ceramics

“…The development of an appropriate electrolyte material with sufficiently high oxygen ion conductivity at lower operating temperatures is one of the major challenges to develop IT-SOFCs. An ideal electrolyte material for IT-SOFCs should have the following characteristics [3][4][5][6][7]:…”