Wednesday, November 28, 2012

1211.6167 (M. H. N. Assadi et al.)

Tuning the doping site of Sb ions in thermoelectric NaxCoO2 by varying
Na content

M. H. N. Assadi, S. Li, R. K. Zheng, S. P. Ringer, A. B. Yu
Through comprehensive density functional calculations the crystallographic and electric properties of both pristine and Sb doped NaxCoO2 (x = 1, 0.875 and 0.75) was investigated. Results demonstrate that the preferred incorporation site of Sb dopants in the complex structure of strongly depends on the Na content. For x = 1, Sb substitutes a Co with margin of stability of 3.76 eV. This margin of stability decreases to 3.60 eV for x = 0.875 and vanishes altogether for x = 0.75. In the latter case, Sb dopants are stabilized by substituting Na site. The influence of the band structure of the pristine systems on Sb behavior was also studied. The results provide new insights to guide the experimentalists in engineering and manipulating the physical properties of NaxCoO2 in the effort of development of high performance sodium cobaltate based multifunctional materials.
View original:

No comments:

Post a Comment