Synthesis and Characterization of Wormhole-Like Mesoporous SnO2 with High Surface Area

Abstract

Abstract High-surface-area wormhole-like mesoporous SnO2 with a tetragonal rutile-type structure was fabricated adopting the hydrothermal strategy using poly(ethylene glycol) (PEG) as the template, tin chloride as the tin source, and urea as the precipitating agent. The effects of PEG with different molecular weights and its concentration, hydrothermal temperature, and calcination temperature on the pore structure and morphology of SnO2 were examined. The physical properties of these materials were characterized by X-ray diffraction, nitrogen adsorption-desorption, transmission electron microscopy, selected-area electron diffraction, infrared spectroscopy, and ultraviolet-visible diffuse reflection spectroscopy. It is shown that the PEG template could be removed by washing, no significant impact of PEG molecular weight was observed on the surface area of the mesoporous SnO2 samples, but the factors such as PEG concentration, hydrothermal temperature, and calcination temperature exerted considerable influence on the pore structure of the SnO2 samples. After the hydrothermal treatment at 120 °C for 29 h with the molar ratio of PEG (with a molecular weight of 6000 g/mol) to Sn of 0.01, a wormhole-like mesoporous SnO2 sample with a high surface area of 161 m2/g and an average pore size of 2.6 nm was generated. The SnO2 samples exhibited good behavior in UV-light absorption. These porous materials are suitable for use as catalysts, supports, and gas sensors.