Gas Humidification Impact on the Properties and Performance of Perovskite‐Type Functional Materials in Proton‐Conducting Solid Oxide Cells

Abstract

Fuel cells and electrolysis cells as important types of energy conversiondevices can be divided into groups based on the electrolyte material. However, solid oxide cells (SOCs) based on conventional oxygen-ion conductors are limited by several issues, such as high operating temperature, the difficulty of hydrogen purification from water, and inferior stability. To avoid these problems, proton-conducting oxides are proposed as electrolytes for SOCs in electrolysis and fuel cell modes. Since water vapor partial pressure (pH 2 O) is one of the main parameters determining the proton concentration in proton-conducting oxides (characteristics of which can be either improved or deteriorated), the pH 2 O control is extremely important for the optimization of the devices' performance and stability. This review provides an overview of the research progresses made for proton-conducting SOCs, especially for the impact of gas humidification on the operability and performance. Fundamental understanding of the main processes in proton-conducting SOCs and design principles for the key components are summarized and discussed. The trends, challenges, and future directions that exist in this dynamic field are also pointed out. This review will inspire interest from various disciplines and provide some useful guidelines for future development of proton-conductor-based energy storage and conversion systems.

Enhancing the Power Output of Direct Carbon Solid Oxide Fuel Cell Using Ba‐Loaded Activated Carbon Fuel

“…To have a much deeper understanding of the impedance spectra, the equivalent circuit was constructed as a configuration of R o ( R h Q h )( R l Q l ). Here, R o is the total ohmic resistance; R h and R l correspond to the high‐ and low‐frequency resistances, respectively; Q h and Q l represent the constant phase element of the high‐ and low‐frequency arc, respectively . All the above evidences indicate that the as‐prepared SOFC is of perfect quality for further research.…”

“…Here, R o is the total ohmic resistance; R h and R l correspond to the high-and low-frequency resistances, respectively; Q h and Q l represent the constant phase element of the high-and low-frequency arc, respectively. [28][29][30] All the above evidences indicate that the as-prepared SOFC is of perfect quality for further research.…”

A Reversible Protonic Ceramic Cell with Symmetrically Designed Pr₂NiO_4+δ-Based Electrodes: Fabrication and Electrochemical Features

“…It is well-known that water vapor partial pressure is a parameter determining proton transport in proton-conducting electrolyte membranes [54]. From the viewpoint of the bulk structure of such membranes, humidification of both atmospheres is favorable, since it results in a decrease both of oxygen vacancies and hole concentrations:…”

A Reversible Protonic Ceramic Cell with Symmetrically Designed Pr₂NiO_4+δ-Based Electrodes: Fabrication and Electrochemical Features

“…It is well-known that water vapor partial pressure is a parameter determining proton transport in proton-conducting electrolyte membranes [49]. From the viewpoint of the bulk structure of such membranes, humidification of both atmospheres is favorable, since it results in a decrease both of oxygen vacancies and hole concentrations:…”