Bulk In-doped Cu₂SnSe₃ samples were prepared by a fast and one-step method of high-gravity combustion synthesis. All the synthesized samples were dense with relative densities of >98%. The influence of Indium-doping on the phase composition of the samples was investigated. SEM and EDS measurements confirm the existence of SnSe and Cu₂Se as secondary phase in the Cu₂Sn_1−xIn_xSe₃ samples. In addition, the experimental results show that there is a solubility limit of indium in the Cu₂SnSe₃ matrix. The thermoelectric properties of the samples were measured in a temperature range from 323 K to 773 K, and the Cu₂Sn_0.8In_0.2Se₃ sample achieved a maximum ZT of 0.65 at 773 K, which was comparable with the best-reported result for Cu₂SnSe₃ materials prepared by conventional sintering approaches. With much reduced time and energy consumption, high-gravity combustion synthesis may offer a more efficient and economical way for producing thermoelectric materials. 

Materials Chemistry and Physics

Available online 20 April 2016