Pr-Doped SrTi_0.5Mn_0.5O_3−δ as an Electrode Material for a Quasi-Symmetrical Solid Oxide Fuel Cell Using Methane and Propane Fuel

Abstract

The use of identical electrodes for both the cathode and the anode in a symmetrical solid oxide fuel cell (SSOFC) can simplify the preparation process and increase the durability of the cell, but it is also demanding on the properties of the electrode including stability, electric conductivity, and electrocatalysis. The doping of variable-valence Mn 4+/3+2+ on the B site of stable SrTiO 3 is explored in this study as both the cathode and the anode for an SSOFC. Though the limit of Mn doping in SrTiO 3 is generally low, the additional Pr 3+/4+ donor on the Sr site of SrTi 0.5 Mn 0.5 O 3 was found to enhance the structure stability, electric conductivity, and electrocatalysis. The cell with Pr 0.5 Sr 0.5 Ti 0.5 Mn 0.5 O 3 electrodes excels under H 2 , propane, or CH 4 /H 2 fuel, providing the cocatalyst was infiltrated on the anode side. The polarization resistance value of Pr 0.5 Sr 0.5 Ti 0.5 Mn 0.5 O 3 was 0.27 Ω•cm 2 as the cathode and 0.33 Ω•cm 2 for the SSOFC using H 2 fuel. The performance under CH 4 / H 2 fuel can be boosted to above 0.9 W cm −2 if Ni/ceria was loaded onto the anode to enhance the methane reforming. This work contributes to a perovskite anode with high Mn doping in SrTiO 3 for application in SSOFC for natural gas with renewable H 2 injection.

Sr-Doped PrCrO3 with Intelligent SrCrOx Cocatalyst for the Fuel Electrode of Reversible Solid Oxide Cells

“…The O 1s XPS spectra of PS30C-O and PS30C-R (Figure a) showed that their oxides split into three binding energy (BE) peaks at 528.7, 531.2, and 532.7 eV. The BE peak at 528.7 eV is attributed to lattice oxygen (M–O), the BE peak at 531 eV is oxygen vacancy, and in the vicinity of 532.7 eV is the carboxyl group. , The BE peaks of Pr 3d spectra (Figure b) at 932.4 and 953.0 eV may be associated with the presence of Pr 4+ and the BE peaks at 927.9 and 948.4 eV may be attributed to Pr 3+ , and the BE peak at 957.2 eV indicates extra-structure, which is present only in the 3d 3/2 form . The Pr 3+ /(Pr 4+ + Pr 3+ ) of the PS30C-R sample was 0.38, which was greater than the PS30C-O (0.24) because a portion of Pr 4+ was reduced to Pr 3+ .…”

A redox-reversible A/B-site co-doped BaFeO3 electrode for direct hydrocarbon solid oxide fuel cells

“…Doping with high-valence elements is regarded as an effective approach to stabilize the structure of perovskites. [23][24][25] For instance, Li et al proposed a co-doped composition, Ba 0.95 La 0.05 Fe 0.9 Nb 0.1 O 3−d , for use as the electrodes of symmetric SOFCs, exhibiting remarkable structural stability against wet H 2 -reduction, which is attributed to the considerably high valence state of Nb. 24 Furthermore, the redox couple Mo 6+ /Mo 5+ is commonly employed as a dopant to achieve structural stability, owing to its variable valence in different atmospheres.…”

Multi-functional perovskite oxide Pr0.6Sr0.4Mn0.2Fe0.7Ni0.1O3−δ as an efficient quasi-symmetric electrode for solid oxide fuel/electrolysis cells

“…Recently, a quasi-symmetric conguration has been studied for solid oxide cells (Q-SSOCs), where two similar electrode materials are optimally combined to further enhance the electrochemical performance of SSOCs. 15,16 This conguration can also be obtained via a follow-up process aer electrode fabrication, such as annealing in a reducing atmosphere. 17,18 A perovskite oxide (ABO 3 ) can be employed as the effective electrode material for an SOC since it has mixed ionic and electronic conducting (MIEC) and redox-stable properties depending on its versatile combinations of A/B cations.…”