Hybrid effect to possibly overcome the trade-off between Seebeck coefficient and electrical conductivity

Previously through a combination of doping certain transition-metals into YB22C2N and heat treatment, Seebeck coefficients were enhanced by up to 220% while simultaneously, electrical conductivity was increased by ∼10,000%. This was a striking result since it overcomes the traditional trade-off between the two; a huge obstacle for enhancing thermoelectric performance. Nano-characterization gives direct proof that this is due to a hybrid/composite effect where highly conductive paths were partially established. At the same time, it is speculated that intrinsic doping modifies the electronic structure of the host material. This hybrid effect may be applicable to a broad spectrum of thermoelectric materials.

“Nanoweb” formation of highly conductive paths in a composite material as a possible way to overcome the tradeoff between Seebeck coefficient and electrical conductivity.Figure optionsDownload high-quality image (168 K)Download as PowerPoint slide