Composite fuel electrode La0.2Sr0.8TiO3–σ-Ce0.8Sm0.2O2-σ for electrolysis of CO2 in an oxygen-ion conducting solid oxide electrolyser
MetadataShow full item record
Composite Ni–YSZ fuel electrodes are able to operate only under strongly reducing conditions for the electrolysis of CO2 in oxygen-ion conducting solid oxide electrolysers. In an atmosphere without a flow of reducing gas (i.e., carbon monoxide), a composite fuel electrode based on redox-reversible La0.2Sr0.8TiO3+σ (LSTO) provides a promising alternative. The Ti3+ was approximately 0.3% in the oxidized LSTO (La0.2Sr0.8TiO3.1), whereas the Ti3+ reached approximately 8.0% in the reduced sample (La0.2Sr0.8TiO3.06). The strong adsorption of atmospheric oxygen in the form of superoxide ions led to the absence of Ti3+ either on the surface of oxidized LSTO or the reduced sample. Reduced LSTO showed typical metallic behaviour from 50 to 700 °C in wet H2; and the electrical conductivity of LSTO reached approximately 30 S cm−1 at 700 °C. The dependence of [Ti3+] concentration in LSTO on PO2 was correlated to the applied potentials when the electrolysis of CO2 was performed with the LSTO composite electrode. The electrochemical reduction of La0.2Sr0.8TiO3+σ was the main process but was still present up to 2 V at 700 °C during the electrolysis of CO2; however, the electrolysis of CO2 at the fuel electrode became dominant at high applied voltages. The current efficiency was approximately 36% for the electrolysis of CO2 at 700 °C and a 2 V applied potential.
Showing items related by title, author, creator and subject.
Perovskite chromates cathode with resolved and anchored nickel nano-particles for direct high-temperature steam electrolysisXu, S.; Dong, Dehua; Wang, Y.; Doherty, W.; Xie, K.; Wu, Y. (2013)Doped lanthanum chromates are now commonly used to prepare composite cathodes for direct steam electrolysis. However, the limitation of electrochemical performances and cell current efficiency by insufficient electro-catalytic ...
Direct electrolysis of CO2 using an oxygen-ion conducting solid oxide electrolyzer based on La0.75Sr0.25Cr0.5Mn0.5O3-delta electrodeXu, Shanshan; Li, Shisong; Yao, Weitang; Dong, Dehua; Xie, Kui (2013)Composite fuel electrode based on redox-reversible La0.75Sr0.25Cr0.5Mn0.5O3 -delta (LSCM) can be operated without a flow of reducing gas. We demonstrate the efficient electrolysis of CO2 using a symmetric solid oxide ...
Highly active and stable Er0.4Bi1.6O3 decorated La0.76Sr0.19MnO3+δ nanostructured oxygen electrodes for reversible solid oxide cellsAi, N.; Li, N.; He, S.; Cheng, Y.; Saunders, M.; Chen, K.; Zhang, T.; Jiang, San Ping (2017)Bismuth based oxides have excellent ionic conductivity and fast oxygen surface kinetics and show promising potential as highly active electrode materials in solid oxide cells (SOCs) such as solid oxide fuel cells (SOFCs) ...