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On average, sixty percent of energy produced is lost as waste heat. Thermoelectric materials may provide a solution to this problem by converting waste heat into useful electrical energy via the Seebeck effect. This has applications in car engines and portable electronic devices such as watches and mobile phones. The TiNiSn half-heusler phase has been known to exhibit thermoelectric properties. Doping the TiNiSn intermetallic with hafnium and antimony on the titanium and tin sites, respectively, can reduce thermal conductivity whilst increasing electrical conductivity within the structure. The combination of these factors leads to an increase in zT (the thermoelectric figure of merit) as compared to the undoped system for optimum dopant concentrations and thus leads to the creation of more efficient thermoelectrics. Traditionally, the TiNiSn phase was synthesised using a high frequency induction process. This study investigated the effect of dopant concentrations in half-heuslers synthesised in a conventional domestic microwave, which yielded reductions in the cost, energy requirement and time of phase synthesis (around 90% reductions in time and energy). The half-heusler product was pressed into a pellet using a Spark Plasma Sintering technique and was characterised prior to and after densification to ensure phase purity. Testing of the thermoelectric properties of these compounds has commenced with preliminary results for the antimony doped sample exhibiting a higher thermoelectric power factor.