Tuning the electronic properties in facile in-situ solution synthesis of SnSe2/rGO nanocomposites with enhanced thermoelectric performance

We report the potential of an SnSe2–rGO composite as a thermoelectric (TE) material and the effect of reduced graphene oxide (rGO) concentration on its TE properties. SnSe2–rGO composites were synthesized via a solvothermal route followed by sintering at 823 K in the presence of argon. The in-situ doping of rGO within the SnSe2 matrix was successfully achieved. The resultant composite showed a significant improvement in electrical conductivity, which displayed a peak value of 2479 S/m (pure SnSe2 = 750 S/m) at 300 K. This enhancement is due to the presence of rGO conductive sheets, which increased the carrier concentration of the overall structure. The investigation confirms that increasing the rGO concentration can improve the thermoelectric properties of bulk SnSe2, where the peak ZT of 0.18 at 750 K was achieved when 11.7% of rGO was added to the SnSe2 matrix.