Thermoelectric power and electrical resistivity of Ag-doped Na1.5Co2O4

Restoration of long range order of Na ions in NaxCoO2 at high temperatures by sodium site doping

“…4. Similar effect was also observed for Ag doped Na 0.75 CoO 2 where the q decreased from 130 lX m for the undoped sample to 110 lX m and 90 lX m for the Na 0.75 CoO 2 sample doped with 5% and 10% of Ag respectively [12]. One plausible explanation for decreasing resistivity, in this case, is an increase in carrier's mobility.…”

“…The data are taken from the following works: K [5], Mn [10], Ni [17]. Cu [14], Zn [16,18], Sr and Y [5], Ru [10], Ag [12,15], Nd [5], Sm [5,11], Dy [11], Yb [5,11], Au [15]. Cu doping, the most stable configuration was Y Co with a formation energy of 3.94 eV for x = 0.75 and 3.74 eV for x = 1.00.…”

Thermoelectric properties of c-axis oriented Ni-substituted NaCoO2 thermoelectric oxide by the citric acid complex method

“…The finer microstructure is effective for reducing the thermal conductivity due to enhanced phonon scattering. It is also apparent that Ä values for NaCo 0.9 Ni 0.1 O 2 are low compared with the substituted NaCo 2 O 4 -based samples reported in other studies, e.g., NaCo 2−x M x O 4 (M: Ti, Rh, Pd, or Ag) [17,26,27]. Fig.…”

Thermoelectric Properties of (Na1−y M y )1.4Co2O4 (M = Sr, Li)

“…Therefore, how to improve the ZT value of NaCo 2 O 4 thermoelectric materials has been a research focus. [13][14][15][16] The sol-gel method is widely used in the fields of material science and ceramic engineering because it has many advantages, such as good system homogeneity, adequate reaction interface, and the possibility to obtain high-purity products. In the present work, Sr/Li-doped Na 1.4 Co 2 O 4 thermoelectric materials were prepared by the sol-gel method.…”