Electrochemical Investigation of Composite Nano La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ Infiltration into LSGM Scaffold Cathode on LSGM Electrolyte

Abstract

As a potential intermediate temperature SOFC cathode, a nano La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) infiltrated into a porous La0. 8Sr0. 2Ga0. 8Mg0. 2O3-δ (LSGM) scaffold cathode was evaluated in combination with a LSGM electrolyte. A XRD analysis revealed resistive phases of LaSrGa3O7 and LaSrGaO4 present in the LSCF/LSGM binary system with sintering over 950 oC. To fabricate a nano catalyst infiltrated into the LSGM scaffold cathode, the porous LSGM scaffold is formed at high temperature (1250 oC). Nano catalysts are coated on the scaffold surface using an infiltration technique and fired at 850oC in air. The cathode polarization resistance (Rp) of nano LSCF infiltrated into the LSGM scaffold cathode was 0.02 Ωcm2, 0.11 Ωcm2, and 0.66 Ωcm2 at 800oC, 700oC, and 600oC, respectively. To improve the oxygen reduction reaction, a Pt/LSCM composite solution was infiltrated into the LSGM scaffold cathode. However, the Rp of the nano Pt/LSCM composite infiltrated into the LSGM scaffold cathode was increased to 0.90 Ωcm2 at 700 oC, despite the Pt has higher electrochemical activity for oxygen reduction than LSCF (Rp for LSCM infiltration was 0.317 Ωcm2 at 700oC).

Fabrication of the Anode Supported Solid Oxide Fuel Cells by Tape-Casting Process and Infiltration Method

“…Also, the solution for infiltration was prepared in the same way as previous studies [11,12]. The Nitrated forms of PrBaMn 2 O 5+δ and La 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3-δ elements were dissolved in de-ionized water.…”

Sustainable Energy Application

“…In this study, CeO 2 -based materials were used as the electrolyte because LSCF cathode shows poor compatibility with traditionally used yttria-stabilized zirconia (YZS) [134]. 0.30 U cm 2 and 250 mA/cm 2 for LSCF and 0.12 U cm 2 and 565 mA/cm 2 for Pt-LSCF at 700 C, respectively [136]. The DC polarization was conducted to identify i 0 when overpotentials (h) of À0.7 to 0.7 V were applied and temperatures varied from 400 to 700 C with an interval of 50 C. Three-electrode cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were implemented [135].…”

Infiltration of SOFC Stacks: Evaluation of the Electrochemical Performance Enhancement and the Underlying Changes in the Microstructure

“…Such nano‐structured electrodes can be obtained by the so called infiltration or impregnation process 8, 9, 11–38. Here, nano‐particles are deposited into a pre‐sintered backbone via an aqueous solution of metal salts.…”