Single source precursors, methods to synthesize single source precursors and methods to deposit nanowire based thin films using single source precursors for high efficiency thermoelectric devices are provided herein. In some embodiments, a method of forming a single source precursor includes mixing a first compound with one of SbX3, SbX5, Sb2(SO4)3 or with one of BiX3, Bi(NO3)3, Bi(OTf)3, Bi(PO4), Bi(OAc)3, wherein the first compound is one of a lithium selenolate, a lithium tellurolate, a monoselenide, or a monotelluride.