Hydrothermal synthesis of SnO2 and SnO2@C nanorods and their application as anode materials in lithium-ion batteries

We report a highly reproducible, large-scale method for the synthesis of SnO2 nanorods with diameters of similar to 4-8 nm, and lengths between 50 and 80 nm. The as-synthesized rods are coated with a thin glucose-derived carbon layer to form a core-shell structure. The SnO2 nanorods were tested as negative electrodes in lithium ion batteries exhibiting improved cycling performance due to their nanosize. The carbon-coated sample was thermally treated at a relatively low temperature, i.e. 550 degrees C. This is because the core-shell structure could not be preserved at a higher temperatures where carbothermal reduction of SnO2 to Sn occurs with a loss of nanostructure. Therefore the resulting SnO2@C sample has a low conductivity. Despite this, we found that the carbon coating stabilizes the electrode, which shows a better cycling performance compared with the non-coated material.