High-Performance Protonic Ceramic Fuel Cells with Thin-Film Yttrium-Doped Barium Cerate–Zirconate Electrolytes on Compositionally Gradient Anodes

Abstract

In this study, we used a compositionally gradient anode functional layer (AFL) consisting of Ni-BaCe(0.5)Zr(0.35)Y(0.15)O(3-δ) (BCZY) with increasing BCZY contents toward the electrolyte-anode interface for high-performance protonic ceramic fuel cells. It is identified that conventional homogeneous AFLs fail to stably accommodate a thin film of BCZY electrolyte. In contrast, a dense 2 μm thick BCZY electrolyte was successfully deposited onto the proposed gradient AFL with improved adhesion. A fuel cell containing this thin electrolyte showed a promising maximum peak power density of 635 mW cm(-2) at 600 °C, with an open-circuit voltage of over 1 V. Impedance analysis confirmed that minimizing the electrolyte thickness is essential for achieving a high power output, suggesting that the anode structure is important in stably accommodating thin electrolytes.

Electrochemical Investigations of BaCe0.7-xSmxZr0.2Y0.1O3-δ Sintered at a Low Sintering Temperature as a Perovskite Electrolyte for IT-SOFCs

“…Another factor that can affect the performance of the cell is the low sintering temperature (1200 °C), which results in a small TPB length, therefore causing a reduced electrochemical reaction at the TPB [25,36,48]. In the present case, the power density of 390 mW cm −2 at 600 °C for BaCe0.7-xSmxZr0.2Y0.1O3-δ sintered at a low sintering temperature is better than the 300 (mWcm −2 ) at 550 °C for BaCe0.5Zr0.35Y0.15O3-δ, which can be improvedby sintering material at a high temperature [49].…”

Direct Alcohol‐Fueled Low‐Temperature Solid Oxide Fuel Cells: A Review

“…BaCeO 3 , in contrast, exhibits higher proton conductivity; however, its stability is relatively poor because of its decomposition into CeO 2 and BaCO 3 in CO 2 environment . Compositional proton‐conducting electrolyte with BaZrO 3 and BaCeO 3 has been recently introduced to enhance the performance of proton conducting fuel cells (PCFCs) operating at low temperatures . Recent reports by Ha and Li demonstrated the use of dense thin film yttria‐doped barium zirconate (BYZ, BaZr 0.8 Y 0.2 O 3−δ ) electrolyted by pulse laser deposition (PLD) technique for thin‐film SOFCs (Figures (c) and 6(d)).…”

Properties on Yttrium-Doped/Undoped Barium Cerate and Barium Zirconate Thin Films Formed by E-Beam Vapor Deposition

“…In barium or strontium cerates, rare earth elements such as Yb, Gd, Nd, and Y are the most common dopants due to their ionic radii size closeness to cerium or zirconium [2]. In various studies [3][4][5], these cerates have shown a relatively high protonic conductivity, but also react in acidic environments to form carbonates in environments with CO 2 and H 2 O. Zirconates are more chemically stable and have better mechanical properties, react poorly in acidic environments, are stable in a CO 2 environment, but have a significantly lower proton conductivity [6,7]. Different approaches were made to find the best combination of a high protonic conductivity and a high chemical and mechanical stability, such as the modifications of technological parameters or the incorporation of the different dopant concentrations [4,8,9].…”