| 초록 |
In this study, macroporous catalytic carbon nanotemplates (MC-CNTs) based on nanoweb-structured carbon nanofibers with various carbon microstructures are prepared from microbe-derived cellulose via simple heating at 800 or 2400 °C. MC-CNTs prepared at 800 °C have amorphous carbon structures with numerous topological defects, and exhibit a lower voltage overpotential of ~8 mV in galvanostatic charge/discharge testing. In addition, MC-CNT-800s exhibit high Coulombic efficiencies of 99.4–99.9% during consecutive cycling at current densities ranging from 0.2 to 4 mA cm−2. However, the carbon structures of MC-CNTs prepared at 800 °C are gradually damaged by cycling. This results in significant capacity losses after about 200 cycles. In contrast, MC-CNTs prepared at 2400 °C exhibit well-developed graphitic structures, and maintain predominantly stable cycling behaviors over 1000 cycles with Coulombic efficiencies of ~99.9%. |
