The purpose of this research is to study the influences of high pressure and Sb doping content on thermoelectric properties of Bi2-xSbxTe3 alloys. Both variables can adjust the carrier concentration of the system to be more suitable for improving thermoelectric properties. In this Letter, Bi2-xSbxTe3 is synthesized by high pressure and high temperature (HPHT). The carrier concentration for the excellent power factor of synthesized Bi2-xSbxTe3 appears in a carrier concentration range. Therefore, we further analyze and present an optimal carrier concentration range, which is favorable for improving thermoelectric properties of Bi2-xSbxTe3 alloys. (c) 2012 Elsevier B.V. All rights reserved.