This paper explores in detail, the microstructures and thermoelectric properties of Te-rich and Te-poor (Bi,Sb)(2)Te-3 alloys. We show that tuning the composition of ternary Bi-Sb-Te type alloys allows us to synthesize a range of microstructures containing a primary solid solution of (Bi, Sb)(2)Te-3 with varying amounts of Te solid solution or a (Bi, Sb) Te compound. Te exists as a constituent of the multilayer domain while (Bi, Sb) Te appears in the thin intercellular regions of the (Bi, Sb)(2)Te-3 dendritic cells. The presence of Te imparts an n-type behavior to the composite while the (Bi, Sb)(2)Te-3 with a small amount of (Bi, Sb) Te exhibits p-type properties. A maximum ZT value of approximate to 0.4 at 425 K was achieved, opening up the possibility of using these alloys for thermoelectric device applications.