Nickel-Containing Perovskites, PrNi0.4Fe0.6O3–δ and PrNi0.4Co0.6O3–δ, as Potential Electrodes for Protonic Ceramic Electrochemical Cells

Abstract

Protonic ceramic fuel cells (PCFCs) offer a convenient means of converting chemical energy into electricity with high performance and efficiency at low- and intermediate-temperature ranges. However, in order to ensure good life-time stability of PCFCs, it is necessary to ensure rational chemical design in functional materials. Within the present work, we propose new Ni-based perovskite phases of PrNi0.4M0.6O3–δ (where M = Co, Fe) for potential utilization in protonic ceramic electrochemical cells. Along with their successful synthesis, functional properties of the PrNi0.4M0.6O3–δ materials, such as chemical compatibility with a number of oxygen-ionic and proton-conducting electrolytes, thermal expansion behavior, electrical conductivity, and electrochemical behavior, were comprehensively studied. According to the obtained data, the Co-containing nickelate exhibits excellent conductivity and polarization behavior; on the other hand, it demonstrates a high reactivity with all studied electrolytes along with elevated thermal expansion coefficients. Conversely, while the iron-based nickelate had superior chemical and thermal compatibility, its transport characteristics were 2–5 times worse. Although, PrNi0.4Co0.6O3–δ and PrNi0.4Fe0.6O3–δ represent some disadvantages, this work provides a promising pathway for further improvement of Ni-based perovskite electrodes.

Mixed Electronic-Ionic Conductivity and Stability of Spark Plasma Sintered Graphene-Augmented Alumina Nanofibres Doped Yttria Stabilized Zirconia GAlN/YSZ Composites

“…Indeed, the composite possessing mixed electronic-ionic conductivity can be used as an anode and even an electrolyte membrane in SOFC with no need to use a current collector [ 11 ]. The most widely used materials for SOFC anodes are various Ni cermets [ 12 ] or mixed perovskites [ 13 ] that suffer from a number of significant drawbacks such as higher resistance, significant grain growth, sulfur poisoning and significantly different thermal expansion coefficients (TEC) comparing to the electrolyte [ 14 , 15 , 16 ]. The use of zirconia-graphene could help to avoid TEC mismatch between an anode and an electrolyte and increase the performance of the device [ 17 ].…”

Understanding the Impact of Sintering Temperature on the Properties of Ni–BCZY Composite Anode for Protonic Ceramic Fuel Cell Application

“…However, the characteristics of anode composite powders used with proton-conducting electrolytes may require different preparation conditions to obtain a high-performance anode. At present, the Nickel cermet perovskite composite materials such as Ni-BaCe 0.54 Zr 0.36 Y 0.1 O 3-δ (Ni-BCZY) have gained great attention for application as the anode in PCFCs [8]. This anode can be used with BCY and BCZY electrolytes for operation at intermediate temperatures (600-800 • C) [9][10][11].…”