Fabrication of Lanthanum Strontium Manganite Ceramics via Agar Gel Casting and Solid State Sintering.

Shiyu Zhang,Jianqiang Wang,Chengzhi Guan,Guoping Xiao,Cheng Peng

doi:10.3390/ma12060848

Abstract

Fabricating lanthanum strontium manganite (LSM) ceramics with certain shapes is important for the design and construction of high-temperature energy conversion and storage devices. Here, we describe a low-cost and environmentally friendly method for fabricating LSM ceramics via agar gel casting and high temperature sintering. This new approach uses temperature tuning to fabricate LSM gel bodies, not only by manufacturing in the secondary process but also by remolding and recycling during the gel casting process. The effect of the sintering temperature on the properties of LSM ceramics was investigated as well. As a result, the porosity and compressive strength of LSM ceramics sintered at 1000 °C are ~60% and 5.6 MPa, respectively. When the sintering temperature increases to 1200 °C, the porosity decreases to ~28%, whereas the compressive strength increases to 25 MPa, which is able to meet the requirement of cathode-supported SOFCs (solid oxide fuel cells).

Highlights

As a representative of perovskite-type oxide system ceramics, lanthanum strontium manganite (La1−x Srx MnO3, LSM) attracted intensive interest because of their outstanding electrical conductivity and catalytic activity [1,2,3,4,5], that make them promising cathode materials for high-temperature energy conversion and storage devices, such as solid oxide fuel cells (SOFC) [6,7,8,9] and molten salt batteries [10,11,12]
Forming LSM ceramics is crucial in the design and fabrication of cathode-supported SOFCs [13], which is associated with structures and shapes and with manufacturing costs
The agar aqueous solution with concentrations of 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, respectively, which was prepared for suspending LSM powders at a constant temperature of 98 ◦ C, and the solid content was controlled at 60 wt% for well-dispersion and moderate-viscosity

Summary

Introduction

As a representative of perovskite-type oxide system ceramics, lanthanum strontium manganite (La1−x Srx MnO3 , LSM) attracted intensive interest because of their outstanding electrical conductivity and catalytic activity [1,2,3,4,5], that make them promising cathode materials for high-temperature energy conversion and storage devices, such as solid oxide fuel cells (SOFC) [6,7,8,9] and molten salt batteries [10,11,12]. Forming LSM ceramics is crucial in the design and fabrication of cathode-supported SOFCs [13], which is associated with structures and shapes and with manufacturing costs. Gel casting is a near-net shape ceramic forming technique that has been widely employed to fabricate electrode-supported substrates for SOFCs [22,23]. Porous LSM cathode tubes in centimeter scale have been fabricated via a typical gel casting process with the binder of polyacrylamide

Methods

Discussion

Conclusion