Over fifty percent of energy is lost as heat. Fortunately, thermoelectric materials can convert this wasted heat into energy. Thermoelectric materials can help reclaim lost heat as energy as well as save money and improve our environment by reducing pollution. The purpose of this experiment is to determine how the thermoelectric properties of the Heusler compound, TiFe2Sn, vary with Sb doping. We hypothesize that substituting antimony on to the tin site will increase the Seebeck coefficient of this material. We will substitute Sb on to the Sn site by preparing a series of samples with the composition, TiFe2Sn1-xSbx, where x = 0, 0.01, and 0.05. The series of samples will be processed by the following methods: arc melting, annealing, and SPS (spark plasma sintering). This will allow us to observe the trends in the thermoelectric properties, such as the Seebeck coefficient, thermal conductivity, and electrical conductivity. Finally, we will characterize the samples with XRD (X-ray diffraction) for purity, SEM (Scanning Electron Microscope) to evaluate at the microscopic level, and ZEM to measure the Seebeck coefficient and electrical conductivity. Results have validated that our desired compound, TiFe2Sn1-xSbx, where x = 0, 0.01, and 0.05, has been successfully synthesized.