Yanyan Liu; Wei Zhang; Baoyuan Wang; Muhammad Afzal; Chen Xia; Bin Zhu
Abstract
Doped ceria electrolytes have attracted intensive attentions owing to their high ionic conductivity, low activation energy, good catalytic activity and feasibility for intermediate or even low temperature operations. This work reports an interesting industrial grade rare earth LaCe1.85Pr0.03Nd0.06-oxide ...
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Doped ceria electrolytes have attracted intensive attentions owing to their high ionic conductivity, low activation energy, good catalytic activity and feasibility for intermediate or even low temperature operations. This work reports an interesting industrial grade rare earth LaCe1.85Pr0.03Nd0.06-oxide composited with sodium carbonate (LCPN-oxide/Na2CO3) as the electrolyte in solid oxide fuel cells (SOFCs). The ‘symmetrical’ anode/electrolyte/cathode SOFC devices are fabricated using LCPN-oxide/Na2CO3 electrolyte and the lithiated transition metal oxide Ni0.8Co0.15Al0.05LiO2 (NCAL) pasted onto nickel foam as both anode and cathode. A power density of 362 mW/cm 2 is achieved at 550 o C for this device. A novel fuel cell device, semiconductor-ionic membrane fuel cell (SIMFC) is introduced here using the LCPN-oxide/Na2CO3 and NCAL as the mixed semiconductor-ionic conductor layer. The peak power density for this new energy conversion device reaches 916 mW/cm 2 at 550 o C with an open circuit voltage of 1.05 V. The results demonstrate that industrial grade LCPN-oxide/Na2CO3 can provide a new approach to utilize the enriched natural resources for next-generation cost-effective fuel cells.
Chen Xia; Muhammad Afzal; Baoyuan Wang; Aslan Soltaninazarlou; Wei Zhang; Yixiao Cai; Bin Zhu
Abstract
Very recently, natural hematite has been developed as an electrolyte candidate for solid oxide fuel cells (SOFCs), because of its considerable ionic conductivity. In this work, to exploit more practical applications of natural hematite, we report a novel mixed-conductive composite made of natural hematite ...
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Very recently, natural hematite has been developed as an electrolyte candidate for solid oxide fuel cells (SOFCs), because of its considerable ionic conductivity. In this work, to exploit more practical applications of natural hematite, we report a novel mixed-conductive composite made of natural hematite (α-Fe2O3) and semiconductor Ni0.8Co0.15Al0.05LiO2-δ (NCAL) to act as membrane layer in a new SOFC technology, electrolyte-layer free fuel cell (EFFC). The Hematite-NCAL composite was synthesized directly from natural hematite and commercial NCAL by solid-state blending and high-temperature calcination. The EFFC were constructed into a sandwich architecture with Hematite-NCAL as the membrane and NCAL pasted-Ni foams as the electrodes. Electrochemical impedance spectra (EIS) and direct current (DC) polarization measurements were carried out to investigate the electrical conductivity of the composite. A high ionic conductivity of 0.16 S cm -1 is achieved by the composite at 600 o C with mass ratios of 7:3 (7Hematite: 3NCAL). When operated at low temperatures, the as-designed fuel cell demonstrated superior power densities of 554 mW cm -2 at 600 o C and 342 mW cm -2 at 500 o C. Considering the competitive cost, abundant resource and eco-friendliness of natural hematite, our findings indicate the Hematite-NCAL can be a highly promising candidate for advanced low-temperature SOFC applications.