Inhibition of chromium poisoning in La0·6Sr0·4Co0·2Fe0·8O3-δ cathode via simple electroless silver plating for solid oxide fuel cells. (8th March 2022)

• Record Type: Journal Article
• Authors: Wang, Zhenwei; Zhao, Shikai; Guo, Xue; Li, Jiao; Hu, Qiangqiang; Feng, Yurun; Yu, Fangyong; Sun, Haibin
• Is Part Of: International journal of hydrogen energy. Volume 47:Number 21(2022)
• Page Start: 11250
• Page End: 11260
• Publication Date: 2022-03-08
• Subjects: Solid oxide fuel cell -- Cathode -- LSCF -- Cr poisoning -- Electroless plating; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2022.01.157
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: La0·6 Sr0·4 Co0·2 Fe0·8 O3-δ (LSCF), one kind of state-of-art solid oxide fuel cells (SOFCs) cathodes, often suffers from the chromium poisoning in the operating condition with Cr-based stainless steel interconnects, resulting in deteriorating cell performances. A simple electroless silver plating method was used to modify the surface of LSCF cathodes (named LSCF-Ag), and the anti-chromium stability of LSCF cathodes was studied. After the Cr treatment for 40 h, the polarization resistance ( R p ) of LSCF cathodes changes from 0.26 Ω cm 2 to 0.62 Ω cm 2 at 700 °C, while that of LSCF-Ag cathodes shows nearly no change (from 0.24 Ω cm 2 to 0.26 Ω cm 2 at 700 °C). In LSCF-Ag cathodes, the formation of AgCrO2 instead of SrCrO4 avoids the lack of excessive Sr in the A site of LSCF, and AgCrO2 has an electronic conductivity two orders of magnitude greater than SrCrO4, thereby exhibiting significant survivability to Cr. The single cell with LSCF-Ag cathodes after Cr treatment shows a stable peak powder density of 288 mW cm −2 at 700 °C while taking wet hydrogen and air as fuel and oxidizer. As a comparison, the peak power density of single cells with blank LSCF cathodes drops by 12%. It is suggested that the simple electroless silver plating on LSCF cathodes is an effective method to suppress cathode chromium poisoning. Graphical abstract: Image 1 Highlights: Ag modified LSCF cathodes are synthesized by the simple electroless plating. Ag loaded on the LSCF cathode can preferentially react with Cr to form AgCrO2 . Ag modified LSCF cathodes show excellent resistance and stability to chromium.