Micrometer-sized nanoporous tin dioxide spheres for gas sensing

作者：Smatt J H; Linden M; Wagner T; Kohl C D; Tiemann M^*

来源：Sensors and Actuators B: Chemical , 2011, 155(2): 483-488.

DOI：10.1016/j.snb.2010.12.051

• Mesoporous
• Nanoporous
• Tin dioxide
• Gas sensor
• Nanocasting

We report the synthesis of mesoporous tin dioxide (SnO2) materials with well-defined particle morphology. The products consist of uniform spheres with a diameter of 5 mu m. The spheres are hierarchically porous with two distinct pore modes of 5.0 nm and 52 nm, respectively. This special porosity is the result of a synthesis procedure which involves a 'hard templating' (nanocasting) process. The product forms an approximately homogeneous monolayer of spheres on a sensor substrate and shows promising response to methane gas with low cross-sensitivity to water. The structural properties and gas-sensing performance are compared with a mesoporous SnO2 material without defined morphology, prepared by a 'soft templating' procedure.