SnO2@MCC and SnO2@C Composites: Synthesis and Properties

Abstract

A method is advanced to prepare SnO₂@MCC composites in the course of hydrolysis of flax cellulose fiber by SnCl₂-containing 10% aqueous nitric acid. The thus-prepared SnO₂@MCC composites have a tin dioxide average crystallite size of 3.8 nm. SnO₂@MCC pyrolysis under an inert atmosphere yield carbon composites SnO₂@C and SnO₂/Sn@C. The physical and chemical properties of the prepared samples were studied by IR spectroscopy, X-ray diffraction, electron microscopy, nitrogen adsorption, and thermogravimetry. SnO₂@MCC pyrolysis at 500°C was found to yield carbon composite SnO₂@C. Temperature elevation to 800°C favors SnO₂/Sn@C composite formation. The carbothermic reduction of tin dioxide involves the formation of metastable SnO starting at 679.8°C; stable crystalline tin is observed to form starting at 784.5°C. The specific surface area of SnO₂/Sn@C carbon composites is 110 m²/g.