Preparation and characterization of Sm and Ca co-doped ceria–La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δsemiconductor–ionic composites for electrolyte-layer-free fuel cells

Abstract

The oxygen enrichment at the interface leads to ionic conductivity enhancement for LSCF–SCDC composites, thus increasing the output of assembled EFFCs.

Study on Zinc Oxide-Based Electrolytes in Low-Temperature Solid Oxide Fuel Cells

“…The power output manifested an almost 2-fold increment over that of ZnO cell. This sharp enhancement is most likely explained by the enhanced ionic conductivity in ZnO-LCP composite through interfacial conduction effect, as confirmed formerly in a number of semiconducting ionic conductors [15,19,35,36]. …”

“…We attributed this phenomenon to the heterophasic interfacial conduction effect at semiconductor oxide/ionic conductor oxide interface regions in hetero-structured composite material [19,50]. Such behavior has been reported in many semiconducting ionic systems, such as La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3−δ -Ca 0.04 Ce 0.8 Sm 0.16 O 2−δ (LSCF-SCDC), YSZ-SrTiO 3 , and CoFe 2 O 4 -GDC [15,20,51]. Furthermore, greater difference is observed between the R e of the two devices, whereby ZnO-LCP possesses smaller R e with values of 0.144 Ω cm 2 at 550 °C and 0.197 Ω cm 2 at 525 °C.…”

“…To address this challenge, an efficacious approach based on semiconducting ionic conductors has been proposed very recently to replace the conventional electrolyte YSZ and SDC [9,10,11,12,13,14,15]. The developed materials have exhibited extraordinarily high ionic conductivity superior to those of YSZ and SDC, showing tremendous potential as membrane layer in LT-SOFCs [14,15].…”

“…The developed materials have exhibited extraordinarily high ionic conductivity superior to those of YSZ and SDC, showing tremendous potential as membrane layer in LT-SOFCs [14,15]. For instance, a breakthrough study on SmNiO 3 reported a high protonic conductivity in such perovskite semiconductor that compare favorably with those of best-performing solid electrolytes.…”

Semiconductor-Ionic Nanocomposite La0.1Sr0.9MnO3−δ-Ce0.8Sm0.2O2−δ Functional Layer for High Performance Low Temperature SOFC

“…It is interesting that no short circuit phenomenon occurred for the SOFC using the LSM-SDC composite layer to replace the conventional electrolyte layer with the pure ionic conductor. All of the OCVs were over than 1.0 V. It may be noticed that even in the case with pure doped ceria as the electrolyte for SOFCs, short circuiting problem with low OCVs (below 1.0 V, more often 0.9 V) has been commonly observed [11,34]. Therefore, both electronic and ionic conductivities were investigated for the LSM-SDC composite samples with various weight ratios.…”