Thermoelectric properties of co-doped (Bi0.98In0.02)2Te2.7Se0.3 / reduced graphene oxide composites prepared by solid-state reaction

Abstract The thermoelectric properties of co-doped (Bi0.98In0.02)2Te2.7Se0.3/reduced graphene oxide composites between 10 - 325 K are presented. X-ray diffraction confirms that the composites adopt a rhombohedral structure with space group R 3 ¯ m . Field emission scanning electron microscopy reveals an interface structure of reduced graphene oxide (rGO). N-type conducting behaviour is observed for all the samples, as ascertained by Hall effect and Seebeck coefficient measurements, with a carrier concentration of 1025/m3. The thermal conductivity and electrical resistivity of (Bi0.98In0.02)2Te2.7Se0.3/0.02 wt% reduced graphene oxide composite is found to decrease by 1.6 and 10 times respectively in comparison with that of (Bi0.98In0.02)2Te2.7Se0.3. The power factor is enhanced by 7 times for (Bi0.98In0.02)2Te2.7Se0.3/0.01 wt% rGO compared to that of (Bi0.98In0.02)2Te2.7Se0.3.