Studying the applicability of different thermoelectric materials for   efficiency calculation in hybrid thermoelectric generator for waste heat   recovery from automobile and steel industry
  In this work, we study the suitability of different thermoelectric materials like $Bi_2Te_3$, $Sb_{2}Te_{3}$, $PbTe$, $TAGS$, $CeFe_{4}Sb_{12}$, $SiGe$ and $TiO_{1.1}$ in estimation of thermoelectric generator's (TEG) efficiency. The efficiency of TEG made up of ${Be_{2}Te_{3}}$ or $Sb_{2}Te_{3}$ gives $\sim$7\% in temperature range of 310 K - 500 K. $PbTe$ or $TAGS$ or $CeFe_{4}Sb_{12}$ gives $\sim$6\% in temperature range of 500 K - 900 K and $SiGe$ or $TiO_{1.1}$ also have remarkable efficiency in higher temperature range i.e $\sim$1200 K. Here, we report the enhancement of efficiency by using hybridization technique for different combination of above-mentioned materials. Hybridization of two different materials of TEG module is done by considering compatibility factor aspect. To this end, the proposed values of overall efficiency of TEG by hybridizing ${Be_{2}Te_{3}}$ and $PbTe$; ${Be_{2}Te_{3}}$ and $TAGS$; $Bi_{2}Te_{3}$ and $CeFe_{4}Sb_{12}$ are 12\%, 14\% and 11.88\%, respectively, for temperature range of 310 K to 900 K, which can be installed in an automobile. For steel industry and spacecraft application (till 1200 K) hybridization of $Bi_{2}Te_{3}$, $PbTe$ and $SiGe$; ${Be_{2}Te_{3}}$ and $TiO_{1.1}$ yields efficiency of $\sim$15.2\% and $\sim$17.2\%, respectively. The proposed results can be treated as a viable option for engineers, who are looking for fabricating TEG in real life applications such as automobile, spacecraft and steel industry. 
Kumar Gaurav and Sudhir K Pandey
cond-mat.mtrl-sci