Cross-plane thermoelectric figure of merit in graphene - C ₆₀ heterostructures at room temperature

The quantum nature of low dimensional materials such as graphene and C ₆₀ is yet to be exploited in thermoelectric (TE) applications. A source of reproducible high-quality graphene is its growth by chemical vapour deposition (CVD) and subsequent transfer onto arbitrary substrates. In this work, heterostructures based on graphene and C ₆₀ clusters were studied by means of the Transient Harman Method (THM). This study revealed a thermoelectric figure of merit, ZT, up to 1.4. The efficiency of the measured devices is attributed to a decrease of the thermal conductivity due to the presence of the layers and a significant value of the Seebeck coefficient (up to 200 μV/K). This type of heterostructures could also be prepared on transparent flexible substrates with a measured ZT of 0.36.