Enhancing the thermopower and tuning the resistivity in Bi2Se3 with Fe-doping

Abstract

We report the synthesis of undoped bismuth selenide (Bi2Se3) and iron (Fe) doped (upto 30%) bismuth selenide (Bi2Se3) powder samples by polyol method. The samples consist of submicron size platelets with thickness ranging between 5 and 10 nm. The temperature dependent thermopower measurements reveal all these materials to be n-type in nature and the room temperature thermopower increases with Fe concentration. The electrical resistivity of undoped Bi2Se3 shows metallic behavior in 5–300 K range, but the Fe-doped samples show semiconducting behavior. Thus we find Fe-doping of Bi2Se3 to be a promising route for tuning the properties of Bi2Se3 for applications.