Hydrolysis of bis(dimethylamido)tin to tin (II) oxyhydroxide and its selective transformation into tin (II) or tin (IV) oxide

• The exclusive formation of Sn6O4(OH)4 from Sn(NMe2)2 by hydrolysis.
• Halide free synthesis to mono phase Sn6O4(OH)4 particles.
• Selective low-temperature conversion to SnO or SnO2.
• Transformation of SnO to SnO2 without the intermediate Sn oxide or metallic tin.

Sn6O4(OH)4, a hydrolysis product of Sn(NMe2)2, is transformed to tin (II) or tin (IV) oxide by solid and solution phase processing. Tin (II) oxide is formed by heating Sn6O4(OH)4 at ⩽200 °C in air or under inert atmosphere. Tin (IV) oxide nanoparticles are formed in the presence of a carboxylic acid and base in air at room temperature. IR spectroscopy, Raman spectroscopy, thermogravimetry (coupled with infrared spectroscopy), powder X-ray diffraction, high temperature X-ray diffraction, scanning electron and transmission electron microscopy are used for the characterization of Sn6O4(OH)4 and the investigation of its selective decomposition into SnO or SnO2. Spectroscopic and X-ray diffraction results indicate that SnO is formed by the removal of water from crystalline Sn6O4(OH)4. SEM shows octahedral morphology of the Sn6O4(OH)4, SnO and SnO2 with particle size from 400 nm–2 μm during solid state conversion. Solution phase transformation of Sn6O4(OH)4 to SnO2 occurs in the presence of potassium glutarate and oxygen. SnO2 particles are 15–20 nm in size.

The synthesis of the tin (II)oxo-hydroxide Sn6O4(OH)4 from [Sn(NMe2)2] and reaction conditions for its selective conversion to SnO, SnO2 and SnO2 nanoparticles are reported.Figure optionsDownload as PowerPoint slide