An Easily Sintered, Chemically Stable, Barium Zirconate‐Based Proton Conductor for High‐Performance Proton‐Conducting Solid Oxide Fuel Cells

Abstract

Yttrium and indium co‐doped barium zirconate is investigated to develop a chemically stable and sintering active proton conductor for solid oxide fuel cells (SOFCs). BaZr0.8Y0.2‐xInxO3‐ δ possesses a pure cubic perovskite structure. The sintering activity of BaZr0.8Y0.2‐xInxO3‐ δ increases significantly with In concentration. BaZr0.8Y0.15In0.05O3‐ δ (BZYI5) exhibits the highest total electrical conductivity among the sintered oxides. BZYI5 also retains high chemical stability against CO2, vapor, and reduction of H2. The good sintering activity, high conductivity, and chemical stability of BZYI5 facilitate the fabrication of durable SOFCs based on a highly conductive BZYI5 electrolyte film by cost‐effective ceramic processes. Fully dense BZYI5 electrolyte film is successfully prepared on the anode substrate by a facile drop‐coating technique followed by co‐firing at 1400 °C for 5 h in air. The BZYI5 film exhibits one of the highest conductivity among the BaZrO3‐based electrolyte films with various sintering aids. BZYI5‐based single cells output very encouraging and by far the highest peak power density for BaZrO3‐based proton‐conducting SOFCs, reaching as high as 379 mW cm−2 at 700 °C. The results demonstrate that Y and In co‐doping is an effective strategy for exploring sintering active and chemically stable BaZrO3‐based proton conductors for high performance proton‐conducting SOFCs.

Reduction in sintering temperature of stable proton conductor BaCe0.35Zr0.5Y0.15O3-δ prepared by sol–gel method and its transport properties

“…Various authors have shown that ZnO, CuO, and In 2 O 3 are the promising sintering aid for these oxides [6][7][8][9][10][11][12]. S. Tao and J.T.S.…”

Y and Ni Co-Doped BaZrO3as a Proton-Conducting Solid Oxide Fuel Cell Electrolyte Exhibiting Superior Power Performance

“…37,38 The high OCV values indicate the dense nature of the BZYNi04 electrolyte membrane (12 μm in thickness) allowing for no gas leakage. Applying humidified hydrogen (≈ 3% H 2 O) as the fuel and static air as the oxidant, a maximum power density of 428, 340, 240, 160 and 94 mW cm −2 was obtained at 700, 650, 600, 550 and 500 37 electrolyte, respectively.…”

“…37,38 The high OCV values indicate the dense nature of the BZYNi04 electrolyte membrane (12 μm in thickness) allowing for no gas leakage. Applying humidified hydrogen (≈ 3% H 2 O) as the fuel and static air as the oxidant, a maximum power density of 428, 340, 240, 160 and 94 mW cm −2 was obtained at 700, 650, 600, 550 and 500 37 electrolyte, respectively. It should be emphasized that, to the best of our knowledge, the power performance obtained in this study is one of the best reported thus far for thermodynamically stable BaZrO 3 -based proton conducting SOFCs, and is compared with the recent literature reports as shown in Fig.…”

“…6b. 24,27,[35][36][37][39][40][41][42][43] A very recent work by C. Duan et al suggests that the application of a proton, oxygen ion, and electron-hole conducting cathode material, BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ , combined with a novel cell fabrication method involving a reducedtemperature firing step (1400…”

Bismuth and indium co-doping strategy for developing stable and efficient barium zirconate-based proton conductors for high-performance H-SOFCs

“…However, doped BaCeO 3 oxides in general show poor chemical stability under CO 2 or steam containing atmospheres, and therefore the trade-offs are proposed with a goal to adjust chemical stability of the BaCeO 3 -based oxides at the expense of the proton conductivity [9,10]. In contrast, acceptor-doped BaZrO 3 oxides owning acceptable conductivity have been already proven to be excellent chemical stability under SOFCs working condition, which might be more suitable for practical applications [11][12][13][14]. However, the serious sintering activity of BaZrO 3 oxides usually generates a large volume of highly resistive grain boundaries.…”