Template Synthesis of Macroporous Tin(IV) Oxide for its Use as an Electrocatalyst Support

Abstract— Owing to its semiconductor properties, tin(IV) oxide is widely used in gas sensors, photo- and electrocatalysis, fuel cells, electrolyzers etc. In this work, macroporous SnO₂ samples are synthesized by impregnating polystyrene (PS) microspheres with sols containing SnCl₄ and alcohol (96% ethanol, isopropanol, or n-butanol). After impregnation, the composites undergo drying and annealing. After drying, the same samples are washed with water for more complete hydrolysis followed by annealing. The resulting SnO₂ samples are studied by powder X-ray diffraction, X-ray photoelectron spectroscopy, X-ray fluorescence analysis, low-temperature N₂ adsorption (77 K), mercury porosimetry, and scanning electron microscopy. The effect of washing with alcohol and water on the porous characteristics and electrical conductivity of the materials is studied.