| 초록 |
Practical application of lithium-sulfur batteries is mainly limited by a low areal capacity around 2 mAh/cm2. In order to achieve a high-areal-capacity cathode, we prepare mesoporous, hollow microspheres with high pore volume. Triazine crystals of melamine and cyanuric acid (MCA) is utilized as structure directing agents, into which additional carbon source, i.e. glucose is introduced. Glucose, trapped inside crystal structure of MCA, is partially carbonized during hydrothermal treatment and then heated to 600 degrees Celsius under nitrogen atmosphere for further carbonization. The resulting microspheres (2~6 μm), MCA-GL-HT, features nitrogen-rich microstructure and hollow porous structure with a pore volume of 2.3 cm3/g and a pore size of 20 nm. MCA-GL-HT enables a high sulfur-loading cathode (~10 mg/cm2) and thereby exhibits an areal capacity of ~8.0 mAh/cm2 at C/5 over 100 cycles with minor capacity loss. |
