A Novel One-Step Solvothermal Route to Nanocrystalline Sn4P3

A novel solvothermal method has been successfully developed to obtain nanocrystalline Sn4P3 in an autoclave based on the reaction of SnCl2 · 2H2O with yellow phosphorus at 160°C for 10 h, with potassium borohydride (KBH4) used as the reducing agent and ethanol as the solvent. XRD, TEM, and XPS examinations investigated the phase, grain size, morphology, and purity of the product, respectively. The product is spherical nanocrystalline Sn4P3 with a hexagonal structure. Potassium borohydride and ethanol played important roles in the formation of nanocrystalline Sn4P3. A possible mechanism is proposed as: under the solvothermal condition, Sn2+ was steadily reduced by KBH4 to atomic Sn; subsequently these newborn active atoms homogeneously combined with yellow phosphorus to form nanocrystalline Sn4P3