CH4-sensing and high-temperature mechanical properties of porous CaZrO3/MgO composites with three-dimensional network structure

Abstract

Uniformly open-porous CaZrO3/MgO composites were prepared by pressureless reactive sintering of CaMg (CO3)2 and ZrO2 with 0.5 mass% LiF additive, and their gas sensing properties to CH4 were investigated at 700-900 °C. At >800 °C, the porous composites showed rapid responses (approximately 1 min) to 1000 ppm CH4 with sensitivities (R0/R) of approximately 1.7. In addition, the fracture strength (σf) of the porous composites was kept constant up to 1300 °C (σf approximately 35 MPa for porosity of 47%), which demonstrated their high structural stability. The results suggest the feasibility of the porous composites as multi-functional filter materials, i.e., simultaneous hot gas-filtering and gas-sensing in one component.