| 초록 |
Direct electrochemical oxidation of solid carbon on the Ni-YSZ anode (C + 2O2- → CO2 + 4e-) is thought to be intrinsically sluggish and thus the main bottleneck in the development of DCFCs. In this study, we report on the effect of functionally graded carbon fuels by taking advantage of tubular SOFC structure and typical characteristics of several additives. Selected additives are mixed with carbon fuels, and the fuels are functionally graded inside an anode-supported tubular solid oxide fuel cell for not only maximizing internal gasification effect but also minimizing detrimental effect due to carbon deposit on Ni anode catalyst. Impregnated Ni catalysts are expected to promote internal gasification by increasing the chemical oxidation of carbon to CO, which can be readily oxidized to CO2 electrochemically on the Ni-YSZ anode. Sb or Sn in secondary fuels is expected to play an important role as an electrochemical mediator in combination with retarding carbon deposit on Ni catalysts. |
